Sharpening Part 29 – An Example

The expectations of life depend upon diligence; the mechanic that would perfect his work must first sharpen his tools.
Confucius

In this article in our series about sharpening Japanese woodworking blades your always humble and obedient servant will try to bring all the information provided in previous articles together into a single practical example. That does not mean the entire contents of those articles are repeated here, however, so please refer to the previous articles if things become confusing. I have provided some links in the text, and provided links to all the articles at the end.

But before we dive into our practical example, I would like to create some context.

Paying Debts

The purpose of this blog, as I have mentioned before, is not to sell stuff or attract clicks but to help our Beloved Customers increase their knowledge and improve their skills in maintaining and using the high-quality hand-forged professional-grade woodworking tools we purvey.

Another purpose is to pay a debt of the kind that can’t be recorded on paper, only in the heart.

In this series of posts I have carefully NOT promised quick and easy results, nor have I given abbreviated explanations or promoted dumbed-down techniques tailored to fit neatly within the publishing parameters of a book, magazine article, or a pretty little video. This is because the series is not about me, or my skills, or what I think is best, or selling stuff but rather helping our Beloved Customers obtain real long-term results and life-long skills of the sort expected of professional Japanese woodworkers. And since I can’t instruct them directly, our Beloved Customers must truly understand the principles and techniques so they can train themselves. Fragmentary instructions and short-cuts would be far easier to write about, but risk creating more confusion than progress.

I share many experiences in common with most of our Beloved Customers, but I’ve also had some unusual experiences working with and being mentored by extremely accomplished Japanese professional craftsmen including sword sharpeners, tool sharpeners, carpenters and joiners. None of those gentlemen charged me a notched nickle for their instruction. Likewise, I have never sought compensation for teaching others those same techniques. And so we come to the other reason for this series, namely to pay those gentlemen back for the time they spent and the kindness they showed me.

So gird up your loins, recall the information and techniques presented in the previous 28 articles in this series, and let’s sharpen a blade.

Removing Damage and Correcting the Bevel

I will not even try to deal with all the possible starting points for sharpening a woodworking blade, but in this example we shall assume a starting point of the lands surrounding the hollow-ground area at the blade’s ura being already flat, planar, and polished. If your blade is not in this condition, follow the instructions at the end of this section. We shall also assume the edge has a small chip that must be removed first. These conditions will cover 80% of sharpening jobs.

If the blade’s cutting edge bevel angle is where you want it to be, the bevel is already flat, and the blade isn’t damaged, please skip to Step 11 below.

1. Examine the Bevel Angle: Check the bevel angle with your bevel angle gauge. 27.5° ~ 30° for plane blades, 27.5° ~ 35° for oirenomi and atsunomi. No less than 24° for paring chisels.

2. Correct the Bevel Angle: If, based on your check in the previous step and the blade’s actual performance, you determine the bevel angle needs to be adjusted, correct the bevel angle using your 400~800 grit diamond plate or diamond stones or FLAT carborundum stones either free-hand or using a honing jig like the Lie-Nielson product, the Eclipse jig, or whatever catches your fancy. If you use a honing jig, you may want to add a drop of oil to the moving parts before they get wet. Be careful to avoid making a skewed or curved (cambered) cutting edge unless that is specifically what you need.

3. Examine the Edge: Examine the blade by eye and touch. Stroke the cutting edge with your thumb (over and away from the edge not towards the cutting edge!) to confirm its condition, and run a fingernail along its length to check for defects as described in the previous post in this series. Your fingerprints will snag on any rolls or burrs, and your fingernail will detect irregularities invisible to the eye. Assuming there is some minor damage, go the next step. If there is no damage, the bevel is in good shape, and the blade is just dull, skip to step 11 below.

4. Remove Damage: Remove chips and dings from the cutting edge by standing the blade, cutting edge down, on a flat 1000 grit stone, with ura facing away from you, tilted a few degrees from vertical towards you, and pull the blade towards you without applying downward pressure. Usually one or two light strokes will suffice. The goal is to remove damage by creating a flat at the cutting edge. Examine the flattened edge with eye, fingertip, and fingernail to see if the chip or defect has been removed. Repeat until it’s gone. Don’t overdo it. Whatever you do, don’t allow the blade to become skewed! This method takes a bit of courage the first time, but it is the quickest, surest, and most economical way to get the job done.

5. Clean the Blade: Carefully clean grit and mud from the blade and the honing jig’s wheel (if you use one) to prevent contaminating the next stone. This is important.

6. Check and Color the Bevel: Check the bevel frequently to confirm full contact. You might blacken the bevel with a marking pen or Dykem to make it easier to monitor progress. This step is worth repeating between stones because it is helpful in monitoring what you cannot see otherwise.

7. Sharpen on the Rough Stone: This is the most important stone in the process. Now that all the damage has been removed and the bevel is flat and in good shape, we need to abrade the bevel until the flat we made in step 4 is gone and we have created a minuscule, tiny, clean burr. Sharpen the blade’s bevel on your roughest diamond plate or FLAT carborundum stone. If sharpening freehand, take short strokes. Always use the entire face of the stone, including corners, edges and ends as described in the previous post in this series. Turn the stone end-for-end frequently to compensate for your natural tendency to work some areas of the stone harder than others. Watch the edge carefully to make sure the width of the flat made at the cutting edge in Step 4 above gradually decreases in width evenly along the cutting edge’s length. If the flat becomes narrower at one corner than the other, apply extra pressure at the wider side, or hang the corner of the blade’s narrower side off the stone for a few strokes to correct. Stop when the flat is gone, and a clean, uninterrupted, but barely detectable burr is created. With practice, you should be able to do this without a honing jig. When using all the stones and plates in this process, keep them wet at all times, and add water as necessary. If the stone becomes dry, not only will it clog and stop cutting efficiently, but friction may cause localized heating of the thin metal at the cutting edge softening it. Remember, you’re violently tearing metal from an extremely thin cutting edge. You cannot see it and your fingers cannot feel it but this destruction heats up metal at that thin edge, so cool it down with water.

8. Check the Burr: Your fingertip will feel the burr long before your eye can see it. Stop when you have a small, uniform burr without interruptions the full width of the blade. Confirm this with your fingernail. Anything beyond this is just wasting metal and stones. With practice, this process will go very quickly, and you can move onto the next stone while the burr is barely detectable.

9. Create Skewed Scratches: When you have a uniform burr, work the blade sideways, or at an angle, on the stone to create diagonal scratches on the bevel removing the straight-on scratches the stone produced.

10. Clean the Blade: Wipe and wash the blade (and the honing jig’s wheel, if you are using one) to remove grit and mud. This is very important to prevent contamination of finer-grit stones.

At the conclusion of step 10, the bevel will be flat, uniform, and at the correct angle. The flat you created on the cutting edge during step 4 above will be gone, and you will be able to just detect a full-width tiny burr using your fingers.

For the next steps, keep the blade attached to the honing jig if you used one in the previous steps. Otherwise, sharpen freehand if you can. Don’t let the honing jig become a crutch that slows you down and prevents you from developing control.

Normal Sharpening Procedures

This is where the sharpening process normally starts when the blade is not damaged and the bevel is in good shape but only needs to be sharpened. It usually does not include a honing jig which can only slow things down.

11. Check and True the Medium-Grit Stone: You may decide to use more than one medium grit stone. I mostly use a 1000 grit at this stage, but may use a 2,000 grit stone as well. Whatever stone you use, it must be clean and flat. As described in previous posts, you need to check the flatness of your stones frequently with a stainless steel straightedge. To do this, wash any mud off the stone and pad (don’t rub) the stone’s face dry with a lint-free clean cloth or paper towel. Hold the stone up to a light source, place the straightedge along the stone’s length, across its width, and across diagonals to check for light leaking between stone and straightedge. Make a pencil mark, such as a line or circle, on high spots using a wide carpenter’s pencil. Once you understand if and how the stone’s face is distorted, flatten it using whatever method you prefer, a diamond plate/stone, a specialized truing block, or my preferred method, another stone of the same grit. If you use my method you won’t need to worry about grit contamination and can save time and money by truing two stones at the same time. Six of one, half-dozen of the other.

12. Sharpen on the Medium-Grit Stone(s): Work the blade’s bevel on your medium-grit stone in short strokes using the stone’s entire face from side to side, end to end, and corner to corner, turning the stone end-for-end frequently and being careful to avoid rocking the blade. A bulging bevel is bad news, Bubba. You will know you are done with this stone when all the diagonal scratches from the previous stone, especially at the extreme edge, have been removed. The burr may or may not have evaporated by now, so check with your fingerprints and fingernail. If it still remains, it should be just barely detectable. If it is still big, you need a few more strokes on this stone to shrink it. Using a loupe at this point will be informative. End your work on this stone by creating some new diagonal scratches on the bevel erasing all the previous straight scratches.

You may want to repeat this step using another medium-grit stone, such as 2,000 grit, to save wear on your finishing stones. Either way is fine.

13. Clean the Blade: Wipe and wash the blade (and the honing jig’s wheel, if you are using one) to remove grit and mud. This is especially important at this stage in the sharpening process. Remove the honing jig at this point if you have been using one.

14. Polish on the Finishing Stone: Move onto your finishing stone, usually a 6,000~10,000 grit synthetic stone. This may not or may not be the final finishing stone you choose to use. Be sure it is flat, uncontaminated with grit from rougher stones, and wet. You may want to use your nagura stone to create a slurry from the stone’s corners and edges that will accelerate the polishing process. Be sure to keep the blade’s bevel in close contact with the stone’s surface on both the push and pull strokes. When all the diagonal scratches from the previous stones are gone, you are done with this stone. If there is still a burr left after the medium-grit stone, it should have evaporated by now. If not, the burr was probably too big to begin with and your technique needs refinement.

15. Examine the Bevel: Take a good look at the polished bevel. Are there still scratches left from the previous stone? This may be because you did not remove all the scratches from previous stones. Or it could be because this stone or previous stones in the series were contaminated with dust or rougher grit. If so, you should figure out why and correct the cause before the next sharpening session.

16. Polish the Bevel Using the Final Finishing Stone: This step may not be necessary, depending on the time available, the degree of sharpness required, and your inclinations. This extra polish probably won’t make a significant difference in the cutting tool’s cutting performance so is often abbreviated during a busy work day. If you use a natural finishing stone or a 10,000+ grit finishing stone, this is the time to use it. Simply repeat the process in step 14 above, but be sure to apply light pressure, keep the stone at least a little wet, and sharpen on both the push and pull strokes. The final finishing stone serves a polishing function, and because it’s grit is so fine, it lacks the ability to distort the bevel badly, so you can take longer strokes and polish the blade on both the forward and return strokes.

17. Polish the Ura: With the bevel polished as finely as you intend it to become, polish the ura on the final finishing stone only. Place the last 1/2” of blade’s length on the stone’s edge (the stone MUST be flat) with the cutting edge parallel with the stone’s length, and the rest of the blade hanging off the stone but supported by your right hand. Press down on the bevel with two or three fingers of your left hand. Be sure to apply even pressure with these fingers. These fingers press down only and do not move the blade. The right hand pushes the blade back and forth and onto and off-of the stone. Take light strokes focusing pressure on the extreme cutting edge, but without lifting the blade’s head.

18. Polish the Bevel (Again): After several strokes on the ura, polish the bevel.

19. Alternate Between Ura and Bevel: Go back and forth polishing the ura and bevel, but keep in mind that you want to limit the number of strokes on the ura side (assuming it’s already highly polished as discussed above).

20. Examine the Edge: Check the full length of the cutting edge frequently with your eyes, fingertips and fingernail. The burr should be gone entirely. The edge should be sharp, and absolutely smooth. All the rougher scratches from previous stones should have disappeared. I make a final sharpness test by shaving an ultra-thin slice of skin from a callous on a finger allowing my bones to sense the degree of sharpness. This method is much more accurate than shaving hair off the arm. If you try it please don’t draw blood.

21. Clean, Dry and Oil: After you are done sharpening the blade, rinse it with clean water or sharpening solution (Item 5 in Post 17) and wipe it dry on a clean cloth or paper towel. You may want to strop it lightly on a soft clean cloth (or the palm of your hand, if you are confident in your abilities) to remove hidden water. I recommend applying a spray liquid rust preventative to the blade that displaces moisture, such as CRC Industries’s 3-36 or WD-40. CRC3-36 is paraffin based, floats water out of the blade’s nooks and crannies, and leaves a film that will prevent corrosion long term. However, please note that, while WD-40 is readily available, very convenient and displaces moisture, it evaporates entirely and is therefore not adequate for long-term corrosion protection. If you are going to use the blade right away, a little oil from your oilpot is cheap, convenient, and will do the job just fine.

With practice, and assuming you have not let your stones become too distorted, this entire process from Step 1 should take no more than 10~15 minutes. This assumes the blade is chipped or damaged and you need to correct the bevel or use a honing jig. Honing jigs slow the process down but are convenient when using rough stones and coarse diamond plates.

If the blade is in good shape and just needs normal sharpening, the goal should be 5 minutes from the medium grit stone in step 11. If you can’t do it that quickly right away, don’t rush, just practice and get a little quicker each time: Remember the turtle with the sail: F e stina Lente: Slow is smooth; Smooth is fast.

Note: If you are sharpening a new blade, or the ura needs to be trued and/or repaired, work the ura on all the stones used in the steps above, but be careful to limit the number of strokes on the rougher stones to the absolute minimum. Also, instead of keeping just 1/2” of the blade’s length on the stones, move it diagonally in and out towards the blade’s center to prevent the stones from digging grooves into the lands at the right and left of the ura. Use special care during this process.

I recommend covering at least your finishing stone with something when you are not using it to protect it from contaminating dust. I simply wrap mine in a sheet of newspaper. It doesn’t take any time or money. Some stones prefer to read the sports pages, others prefer current affairs or the fashion page. Mine seem to like the funny pages. Just ask them.

Conclusion

I am confident the techniques described in this series of posts will prove useful if sharp tools matter to you. Your tools may not talk much, but if you train yourself in these techniques I promise they will sing their appreciation.

I trust the gentlemen that taught and mentored me would be pleased with the content in this series of articles, although I doubt they have time for reading nowadays. I’ll make the introductions, so let’s ask them when we meet again in the big lumberyard in the sky.

In the next and final article in this series, we will consider how to restore a worn-out ura in a plane (and maybe even a chisel) blade. Is there no end to the excitement? Until then, I have the honor to remain,

YMHOS

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Links to Other Posts in the “Sharpening” Series

Sharpening Part 28 – The Minuscule Burr

Do the difficult things while they are easy and do the great things while they are small.
Lao Tzu

A key milestone Beloved Customer should aim for when sharpening a blade is the production of a “burr” at the edge when abrading the bevel (not the ura) using the first rough stone in the series. The formation of the burr indicates that the extreme edge of the bevel side of the blade has probably been abraded enough.

In this post in the Sharpening Japanese Tools Series, we will examine how to raise this burr and why it is important to do so, how to use the burr to test the condition of the cutting edge as you are sharpening, and how to transition from one stone to the next finest stone in the series

Raise a Burr

The steps in creating and then abrading away a burr. The size of the burr in step 2 is grossly exaggerated for clarity. Indeed, unless severe damage to the edge needs to be repaired, you should not normally be able to detect the burr by Mark 1 Eyeball alone.

Japanese plane and chisel blades tend to have harder steel at their cutting edges than Western chisel and planes, and consequently, their steel does not exhibit the plastic deformation necessary to readily produce large burrs, or “wires” as some people call them, when being sharpened. In fact, “burrs” on professional-grade Japanese chisel and plane blades may be difficult to detect.

The key point to remember is that the formation of a burr is only a milestone in the sharpening process, not a goal. A clean, uniform, smooth burr signals the elimination of all major defects, chips, and dents at the cutting edge. Indeed, if we seek an efficient cutting edge, we must remove through abrasion enough metal to also remove the deepest defect in the cutting edge. But regardless of the ductility of the steel, a large, loopy burr or “wire” is not desirable because it will tend to break off prematurely leaving a jagged, ragged edge that will actually set back the sharpening process.

The milestone we need to pass in the sharpening process as soon as possible is the creation of a barely-detectable, tiny and clean burr. My advice is to produce it by abrading only the bevel side of the cutting edge on your roughest stone, although you may not be able to test if it is clean until after a few strokes on the medium-grit stone (1000 grit).

As we discussed in a previous post in this series, the way to keep the size of the burr minimal and the blade’s bevel flat is to focus the pressure of abrasion as close to the extreme cutting edge as possible, but without overbalancing and gouging the stone and dulling the edge. This is the most essential skill in freehand sharpening.

Now that we have a burr, let’s test it.

Testing the Burr

As you are working to produce the burr, you will need to frequently and quickly test its progress, but that can be difficult, if not impossible, to do by eye alone.

To make this process easier and quicker, rub the pad of your thumb or finger over the ura’s edge, away from the cutting edge, thank you very much, when using your rough stones. Your fingerprint ridges will snag on the burr long before you can see it. If the edge is chipped or damaged, the burr will not be consistent but will be interrupted at each defect. There is nothing at all to be gained and much to lose by allowing the burr to become larger than absolutely necessary, so pay attention.

Once you have produced a small burr the full width of the cutting edge, and confirmed its existence with your fingertips, you then need to test it for defects. If you run your fingernail along the burr’s length (the width of the blade), your fingernail will snag on nicks and defects in the burr, something your nerves can sense long before your naked eye can detect them. Keep working the blade’s bevel on the rough stone until the edge and/or burr is consistent across the full width of the blade, and free of nicks, dents and chips.

In the case where you need to remove serious damage to the cutting edge, you may want to use a loupe to ensure the defect has been transferred entirely to the burr and no longer remains in the cutting edge.

In the case of quality Japanese woodworking blades, if you are careful to focus the abrasive effect of the stones on the extreme cutting edge instead of the rear of the bevel, the burr created before moving onto the medium grit stones should be barely detectable or even non-existent. Once again, except in the case of removing large nicks, chips or other severe damage, creating a big burr is not only a waste of time, stones and steel, but if, heaven forfend, the large burr is torn off during sharpening, it will leave behind a tragic amount of damage that must be repaired by once again abrading the edge and raising a new burr. Don’t start chasing that tail.

Best to create just enough of a burr to confirm that damage has been removed and then encourage it to evaporate.

Don’t forget to check the angle of the bevel with your hand-dandy bevel gauge. See the section on Pixie Predation Prevention & Pacification in Part 11 of this series.

After the burr is in good shape, polish the bevel on the medium and then fine stones. The burr will be polished away evaporating without special effort.

Finally, polish the ura side of the blade on the finest stone you intend to use. Feel the burr with your fingerprints and check it with your fingernail. Then polish the bevel on the fine stone. Repeat this front and back polishing process until the burr is polished away entirely.

Assuming the ura is already polished on your finest finishing stone, you shouldn’t need to touch the blade’s ura again on any stone until the final finishing stone.

Transitioning From One Stone to the Next

Recall that the purpose of each stone used after the roughest stone in the series is simply to replace the deeper scratches left by the preceding stone with finer scratches. In fact, there is nothing to be gained and much to lose by moving onto a finer stone before all the scratches from the previous stone have been replaced, so please check that all the scratches from the previous stone have been polished out before moving to the next.

This is not always easy to confirm without magnification, so to make it easier and surer, I suggest you skew the blade’s bevel on all stones but the final finishing stone for the last 3 or 4 strokes creating new diagonal scratch marks on it.

These skewed scratches will be at a different angle than those produced by the next stone, of course, and will be easy to differentiate from the new scratches with the nekid eye. When the next finest stone removes them entirely, you will know you have probably spent enough time on that stone, and can go to the next. But don’t forget to skew the blade again before going to the next stone.

Of course, there is no need to skew the blade on the final finishing stone.

Summary

We have discussed three important sharpening techniques in this article which you must master if you have not already:

Raise a burr by abrading the blade’s bevel on your rough stones using your skillful technique;
Test the burr for size and completeness using your fingertip ridges, and for defects using your fingernails. If the burr is incomplete or has detectable defects, continue to work the blade on the rough stones on the bevel side only until the burr is good.
Skew the blade during the last 3~4 strokes on each stone (except the final finishing stone, of course) to create diagonal scratches. When all those diagonal lines are polished off by the succeeding stone, you will know it is probably OK to move onto the next finest stone in the series.

You now have powerful tools at your disposal that can sense the state of a steel blade as thin as the edge of nothing, and without using your eyes, tools you’ve always had and which didn’t cost you a thing. How’s that for value? (ツ)

Be forewarned, however, that if you use these techniques you may be forced to choose between a glamorous career as an international professional fingernail model or the quiet life of an expert woodworker. What to do, what to do…..

In the next and final post in this series we will use all the aspects of the sharpening process discussed previously to sharpen a blade step-by-step. Be there or be square.

YMHOS

The University of Tokyo’s Yasudo Kodo building hidden behind Autumn Ginko leaves.

If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.

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Sharpening Part 27 – The Entire Face

A beautiful face: Oohirayama Lotus stone

If a dog will not come to you after having looked you in the face, you should go home and examine your conscience.
Woodrow Wilson

The subject of how to use the face of your sharpening stone is so basic and seems so unimportant that few give it the attention it warrants. But it is not trivial: it deserves its own post because it can truly make a big difference in the time and money you spend sharpening.

Money Down the Drain

Instead of focusing his attention on the blade alone, a wise man will make a conscious effort to use the entire face of his sharpening stone from edge to edge, end to end, and corner to corner instead of digging an oval swamp in the center of it’s poor abused face.

This habit will help to keep a stone’s faces flatter over more strokes longer, saving time truing the stone, and extending its life thereby saving money.

Remember that you paid money for the stone, the entire stone, not just the hollowed-out oval area in the center most people create when carelessly sharpening. How much of a stone do most people throw away? Idunno,… 20% maybe? Assuming this approximation is correct, just for the sake of illustrating a point, if you paid $100 dollars for the stone, that means $20 was turned into mud and washed away without providing Beloved Customer any benefit at all. And don’t forget the time you spent cutting down those high spots to keep the stone’s face flat. That makes it more than a $20 loss if you count your time worth anything, which you should.

Why not use the sides, ends and corners of the stone’s face too?

Developing Good Habits

When developing these intelligent work habits, it helps to cross-hatch the stone’s surface with a carpenter’s pencil to help you keep track of the areas you have not yet touched. Never fear, for while industrial diamonds are made from graphite, the form of graphite in pencil lead is still softer than the finest sharpening stone and won’t affect the sharpening process a bit.

Also, before and while sharpening, frequently use a thin stainless steel ruler to check the stone’s face lengthwise and crosswise at various locations, and of course on the diagonals to monitor wear. Don’t guess, lazy bones, examine. Between ruler and pencil you may discover you have developed less-than-efficient sharpening habits. With some thought you will also figure out how to change those habits so your sharpening efforts will be quicker and more cost-effective.

Before long, you will be able to detect uneven wear and warpage fairly reliably without using either tool as much, so stick with it until you do.

Hang Ten

One conundrum you have probably already discovered is that it is impractical to use the extreme right and left sides and both ends of the stone’s face to sharpen a blade. Or is it?

Here is wisdom: Teach yourself how to sharpen a blade’s bevel with one corner of the blade hanging off the stone part of the time, alternating evenly and frequently between right and left corners, of course. Strange as it may seem this technique is effective at not only keeping your sharpening stone flatter and making it last longer, but for keeping the cutting edges of your blades straighter. If this doesn’t make sense to you, think about it real hard. Then give it a try and you will see what I mean.

And since you are taking short strokes anyway, why not work the blade crosswise at the ends of the stone? A lot of expensive stone going to waste there, I’d wager.

I hate to sound like a broken record, but you will find that making short strokes will make it much easier to use the entire face of the stone.

If you feel this post needlessly states the obvious, or is “verbose,” allow me to remind Gentle Reader once again that the purpose of this blog is not to provide entertainment, sell stuff, troll for clicks or to trip and roll subscribers into Google Analytics’ s*thole, but to help our Beloved Customers develop good work habits through education. Some of them are newbies, and others are old hands, but if I were to write only for the professionals then I would be neglecting the newbies, so if you know this stuff already please congratulate yourself and celebrate your good fortune by buying a new carpenter’s pencil.

YMHOS

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Sharpening Part 26 – The Taming of the Skew

My relationship to reality has been so utterly skewed for so long that I don’t even notice it any more. It’s just my reality.
Ethan Hawke

The Taming of the Skew

Beloved Customer has of course noticed that it is easier to keep a blade stable when sharpening its bevel if you skew it on the stone. There is nothing wrong with skewing the blade so long as you understand the natural consequences of doing so and compensate for them appropriately. In this article we will examine some of those consequences.

The first and most immediately obvious consequence of skewing the blade when sharpening it is that the blade tends to wear-out, or hollow-out, the center area of the sharpening stone’s face quicker. This is inefficient, wasting time and stones, but can be compensated for if you pay attention and work the blade evenly over the stone’s entire face, including the edges, ends and those pesky corners. BTW, this is not a kindly suggestion but a commandment.

Second, skewing the blade usually results in the nut holding the blade placing uneven pressure on it, with the natural result that the blade wears unevenly, and quite often, develops a skewed cutting edge. Think about it.

In addition, the leading corner is exposed to more fresher, sharper, larger grit particles (which cut more aggressively) than the trailing corner. As a result, the blade’s leading corner tends to be abraded more, causing the blade’s edge to gradually become skewed or rounded in shape over many sharpening sessions. This is definitely bad, and is often mistaken for the work of those devilish iron pixies, especially in the case of kiwaganna and other skewed-blade planes, causing self-doubt, mental anguish, and even piranha in the head (aka “going bananas“). But if you are aware this can happen, and pay attention, you can easily compensate for this tendency thereby avoiding months of expensive psychoanalysis by Dr. Alonzo and the need to consume pallets of his pretty purple pills.

Third, and I have no way to confirm this, I am told by the guys with microscopes that diagonal scratches at the extreme cutting edge leave it a tad weaker, causing it to dull just a bit quicker.

The way to remove problematic diagonal scratches, BTW, is to make the last few strokes on the finishing stone perpendicular to the cutting edge.

So in summary, habitually skewing a blade while sharpening it is not ideal and should be avoided, but is not catastrophic. It will make one’s sharpening efforts a little less efficient and may cause blades and stones to become distorted, but these negatives can be dealt with, at some cost.

Please read the quotation at the top of this article and consider whether or not your sharpening reality has become skewed without your realizing it. Your humble servant confesses, and Dr. Alonzo can confirm, that his was indeed skewed for a long time.

These aren’t things you wouldn’t have figured out for yourself eventually, Beloved Customer, but now, at least if you pay attention, you’re a few years ahead on the learning curve. In the worst case, at least ignorance isn’t an excuse anymore. And there’s always those pretty purple pills to take the edge off (ツ).

YMHOS

If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.

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Sharpening Part 25 – Short Strokes

Festina Lente Doors in the Palazzo Vecchio, Florence, Italy

Long-term consistency beats short-term intensity.
Bruce Lee

We have discussed many details about sharpening in this series, and while this may be the shortest article of the bunch, it is by no means the most insignificant. For some it will be the most difficult technique to master, so classical references shouldn’t prove too onerous.

If Beloved Customer pays attention to their blade’s movement when sharpening, you will notice how each reversal of direction tends to cause the bevel to rock forward and backward on the stone’s face. And what happens when we let the blade go rock-n-rolla? That’s right, the crapulous bulging bevel rears its ugly head and spits stinky sticky stuff in our eye.

Using short strokes, somewhere around 1-½ inch in length, makes it much easier to keep the blade from rocking.

A Gentle Reader named Oskar observed that, following the logic in the previous sentence, shorter strokes result in more, not less, reversals in stroke direction, and therefore shorter strokes should lead to more rocking rather than less. I concur with Oskar’s analysis and conclusion, as far as it goes, and am adding the following clarification to avoid confusion.

A short stroke produces smaller changes in the angles of one’s joints during the stroke compared to the changes during a longer stroke, making it much easier to maintain the bevel at the correct angle on the stone’s face. In other words, the angles of the joints in hand, wrist, arm and shoulder change less during short strokes than in longer strokes, making it easier to manage joints and tendons yielding greater repeatability.

In addition, shorter strokes tend to focus one’s attention on properly indexing the bevel on the stone during each individual stroke, attention that tends to wander more during long strokes. It’s that darn badger again.

Please note that this analysis is simply your humble servant’s opinion, and perhaps not a weighty one at that because I am not a physician, nor have I conducted the physiological studies and dissections upon which a rigorous opinion should be based.

I know that making short strokes feels inefficient, and it is compared to a machine, but Beloved Customer is probably not a Cyberdyne Systems product with a titanium alloy combat chassis. However, with practice, you will find you are able to increase the distance and speed of each stroke, especially as your focus and hand-soul coordination improves and your wrists and elbows relax and become trained.

Long extravagant strokes on rough or medium grit stones are for sharpening axes and kitchen knives, not chisels or planes.

The exception to this rule is the finishing stone, as mentioned in the previous article.

Festina Lente

In conclusion, and in order to improve your classical education, let’s review our latin lesson from the previous article: “Festina lente” translates directly as “make hast slowly.” It is defined in the dictionary as “proceed expeditiously but prudently.” We chose to translate the phrase as “Slow is smooth; Smooth is fast. ”

At least two Roman emperors, one Pope, and the powerful Medici family of the City State of Firenze Italy, back in the days when emperors, popes, and noble merchants had real power measured in armies they controlled and cities and continents they ruled, thought these two words important enough to include in their mottos and coats of arms. The words even appear in the original French version of the tale of the “Hare and Tortoise.”

They are also relevant to sharpening if you are clever enough to understand why.

YMHOS

Bug-nibbled woodwork in the Laurencian Library in Florence Italy with the Medici’s motto of Festina Lente and the turtle with a sail carved into it.

If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.

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Sharpening Part 24 – Sharpening Direction

If you do not change direction, you may end up where you are heading.
Lao Tzu

When using rough stones ( ≤1000grit), and especially when learning basic sharpening skills, it is best to sharpen the bevel in one direction only, lifting the blade off the stone, or at least removing all downward pressure, on the return stroke. The reason for this seemingly inefficient movement is simply that, at least for most people, and until one’s hands and wrists beceome trained, trying to abrade the blade on both push and pull strokes is likely to cause the blade to rock creating the bilious bulging bevel.

There are certainly exceptions to this rule, and we actively encourage Beloved Customer to try to develop the concentration and muscle control required to sharpen in both directions on rough and medium stones, but be aware it may take some years. In the meantime, remember the ancient adage and imperial moto: festina lente, which we chose to translate as “Slow is smooth; Smooth is fast. “

Part of the difficulty of sharpening in both directions is the resulting loss of concentration: the swing of the thing and angle of the dangle are hard to sense. Perhaps another part of it is due to the difficulty of controlling the complicated and constantly-changing angles of bones and joints. Both of these natural mental and physical tendencies can be overcome by talented and determined people given time and daily practice, but in the case of everyone your humble servant has ever spoken with on the subject, it takes years of focused on-the-job practice, and extreme concentration at first to overcome pre-existing bad habits and to avoid developing importune muscle memory.

Which Direction?

At this point you need to make a decision, unless you have already made it inadvertently. That is, whether to sharpen on the push stroke (pushing the blade away from you) or on the pull stroke (pulling the blade towards you). Most people choose the push stroke, as do I, but in reality the pull stroke is actually a little more efficient because the pressure tends to focus closer to the bevel’s front instead of back, and rocking is reduced. Whichever direction you choose, use it consistently.

However, as mentioned in previous articles in this series, and this is critically important, when it comes to the final finishing stone, work the blade back and forth in both directions. The finishing stone is not abrasive enough to change the bevel’s shape, and since you need to polish the last few microns width of blade’s cutting edge, a very tiny amount of unintentional rocking is actually helpful.

Training Techniques

If Beloved Customer is determined to develop the ability to sharpen on both push and pull strokes, your humble servant can share some helpful guidance that was given to me many years ago by a sword polisher.

The first step in training yourself is to begin by lifting the blade from the stone’s surface entirely on the return stroke (either push or pull depending on your preferred direction). All the things mentioned above apply. Becoming proficient with this technique is foundational. Strive to project your senses into the blade traveling over the stone, indeed right down to the last few microns of the cutting edge, becoming Zen Master Bubba.

When you are able to create a sharp edge while maintaining a flat bevel consistently and without much concentration using this “one-way” technique, then move on to the second step, which is to keep the blade in contact with the stone on the return stroke, but relieve all downward pressure. Begin slowly with full concentration and strive for smooth motion. It’s at the transition from one direction to the other where Murphy will toss a banana peel under your heel.

And finally, when you have mastered the “light-touch” technique, try applying downward pressure in both directions, beginning slowly at first and with full concentration striving for smooth motion.

Remember, don’t grip the blade like a thrashing alligator, but hold it lightly in your hands like a small bird: too tightly and it will be crushed; too loosely and it will fly away.

Don’t lock your wrists or elbows, but actively and consciously rotate them to keep the blade’s bevel always perfectly flat on the stone (your stone is flat right, right?). This is very important.

And don’t forget to use your thin stainless steel straightedge and brass bevel gauge frequently to check the bevel for flatness and proper angle.

And as always, relentlessly beat down your inner badger, brutally crush and sow salt on bad habits, and don’t allow new bad ones to take root.

Sadly, this is a skill that, once learned, tends to deteriorate with time unless practiced frequently. As with cherry blossoms, muscles, tendons and eyes are neither static nor eternal. Setsunai, desu ne.

YMHOS

If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.

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Sharpening Part 23 – Stance & Grip

Ok boiz and gurlz, ready to get to work?!

When the show starts, I am in my SpongeBob stance, and I walk like SpongeBob, and the first step that I take, I am SpongeBob.
Ethan Slater

In this post in our series about sharpening Japanese woodworking blades, your humble servant will propose some useful stances and grips to employ when sharpening. I hope we can do a better job than Mr. Squarepants, at least.

Stances

There are several practical stances for sharpening, including standing, sitting on a bucket, a bench or a chair, squatting, kneeling on the floor, or sitting on the floor. With practice, all these stances can be made to work well.

When starting out, however, I think most people benefit from using a standing position with the stones placed on a workbench or table, or on a board spanning a sink.

Whichever stance you choose, locate and be conscious of your center of gravity, (usually just below your belly button), and try to keep it at the same elevation above the floor while moving the blade forward and back.

Flex your knee joints, and loosen your elbow joints and wrists, because locking up your wrists and elbows will make it impossible to avoid rocking the blade. This is important: You must actively concentrate on allowing your wrists to rotate so as to keep the blade’s bevel flat on the stone’s face, because it won’t happen by accident, or because Jesus loves you.

In the case of a normal resharpening job, instead of a major repair, remember the goal that craftsmen have endlessly sought for thousands of years: to abrade and polish the last few microns of steel at the extreme cutting edge, using the flat bevel as an alignment jig.

But don’t let yourself get lost in the weeds; Focus on abrading and polishing the entire bevel. If you do so, the last few microns, which the human eye can’t see, will be in good shape.

Focus the majority of your finger’s pressure on the extreme cutting edge, and less on the rear of the bevel, but without lifting the rear of the bevel off the stone. In the case of Japanese blades, the rear of the bevel is all soft jigane iron and will take care of itself. Yes, it is a balancing act. Yes, it takes focus. Yes, you will make mistakes, overbalance, gouge the stone and mess up the cutting edge a time or two. Everyone since the day the first caveman tried to grind his stone axe on another stone has made that mistake, so don’t worry about it. Remember, you fell off your bicycle the first few tries, scraped your knees and elbows, survived, and now ride like the wind! Yiiiiiihah!

Get a Grip

The way you hold your plane or chisel blade when sharpening it will influence the quality of the results and the stress on your hands and wrists, so it is worth paying attention to.

There are as many was to hold a plane or chisel blade when sharpening as Baskin Robbins has ice cream flavors. And like ice cream, none are right or wrong, except Burgundy Cherry, which of course is superior to all others (ツ)。 In the interest of brevity, we’ll only consider three grip methods here. If you are not using them now, give each a try over a couple of sharpening sessions to see if they are an improvement or not. Feel free to adapt these or develop your own.

The Gorilla Grip

First, let’s examine what I call the “Gorilla Grip.” With the plane blade resting ura facing up, the blade’s long axis pointing at 11:00, and the cutting edge furthest away from you, grip the blade’s sides with your right-hand’s thumb on the left side, ring finger and pinkie on the right, the tip of the middle finger resting on the right corner directly behind the cutting edge, and index finger extended alongside the middle finger. Then lift the blade and roll your ring and pinkie under it.

Rest the tip of the ring finger of your left hand on the left corner directly behind the cutting edge, with your middle finger and index fingers extended and their tips resting adjacent.

Extend your left palm over your right thumb’s last joint, and wrap your left thumb under the blade. You are now ready to rock-n-roll, without the rocking and rolling motion

The advantage to this grip is that it is very strong, ergo “ gorilla.” The downside is the blade tends to end up skewed on the stone because the right wrist must be twisted to keep the blade straight. Also, because the wrist joints are at very different angles with respect to the blade, and it is easy to apply a lot of force, extra care is necessary to keep the wrists firm but loose and rotating in harmony.

Notice how thumbs are poised to fit under the blade’s head

Four fingers pressing down on the blade’s ura as close to the cutting edge as reasonably possible.

Finger position on a chisel. The left hand thumb passes under the blade’s neck supporting it vertically, while the pad presses against the neck’s right side. The right hand thumb passes over the top of the neck, restraining the tool vertically, and presses against the neck’s left side firmly securing the neck between both thumbs. More fingers can press down on the ura in the case of wider blades. Conversely, only one finger can press on narrow blades.

The Three-finger Grip

The other grip is one I call “three-finger,”（指三本） after the most proper way of bowing in Japan when seated directly on the floor (preferably tatami mat) in the “seiza” posture with legs folded underneath the body, both hands touching side by side with the pads of three fingers of each hand extended and touching the floor in front of the knees, and the thumbs and pinkies tucked out of sight. Very proper, especially for elegant ladies.

In the case of the three-finger grip, the blade is oriented directly in front of and on the body’s centerline with cutting edge located furthest away. The hands hold the blade in a more symmetrical fashion than the gorilla grip, with the middle and index fingers pressing down on the blade’s corners closest the cutting edge (depending on the space available), with the thumbs curled under the blade’s head (end opposite the cutting edge), and either the ring fingers or pinkies touching the blade’s sides to assist in lifting it.

The advantages to this grip are less tendency to skew the blade, looser wrists, and better control of bevel angle. The disadvantage is slightly less power because it is harder to get the shoulders over the blade. This is the burgundy cherry version, in your humble servant’s opinion.

The Three-finger Monkey Grip

A hybrid of these two methods is one I call the “three-finger monkey.” Place the right-hand thumb alongside the blade’s left side, instead of under the head forming a combination of the gorilla grip and three-finger grip. This method provides a little more power than the three-finger grip, and less skew than the gorilla grip.

Is one of these grips best? It’s like riding a bike: None are wrong, but some work better than others.

In all three of these grips, most of the pressure will tend to focus at the blade’s corners which can create uneven wear on the ura and a rounded cutting edge. While this may be unavoidable, especially in the case of narrow blades, try to counteract this tendency by focusing the majority of pressure on the centerline of the cutting edge. It seems insignificant, but if left uncorrected, the resulting unbalanced pressure will cause the blade to wear quicker at the corners and become curved. Yes the blade is iron and steel and does not flex much, but it is a verifiable fact that the points where your fingers apply direct pressure will be abraded quicker.

There is a saying in Japan which is quite appropriate when talking about sharpening that says “Dripping water wears away stone.” In this case, just a little differential pressure from your fingertips will shape the blade over many weeks and many passes over the stone, wearing away both stone and steel in ways that can be either useful or not, depending on whether you are the sharp-eyed master of the process or the grunting badger. Please remain aware of this potential.

Chisel Grip

The grip I use on chisels is very similar to the grip for planes, and varies with width.

Like the famous Mexican weather babe Yanet Garcia, the chisel’s long handle shifts its center of gravity towards the butt making it a bit more difficult to manage, so a grip method that is absolutely stable in a single hand is advantageous.

Most solutions involve holding the chisel in the palm secured by middle finger, ring finger, and pinkie, with the index finger extended and centered right behind the cutting edge.

The index and middle fingers of the other hand can also be pressed near the edge and the thumb wrapped underneath the handle.

Polishing the Ura

When polishing the ura of a blade, be it plane or chisel, make sure the stone is flat. If it isn’t, you will regret it later without realizing why.

Let’s look at a plane blade first. Notice in the photo above how my right hand is curled under the blade’s head supporting it while my thumb presses down on the bevel close to the cutting edge, a grip that makes it easy to apply a lot of pressure precisely while maintaining control of the blade.

Two fingertips of my left hand are pressing down on the bevel for a total of three pressure points. The thumb can press down as light or hard as you feel is necessary, but it typically applies the highest amount of pressure. It’s important the left hand fingertips apply equal downward pressure to avoid creating uneven wear (unless one corner of the blade specifically needs more pressure applied).

Try to remove nearly all the weight of the blade’s head from the stone so that all but a tiny amount of applied pressure is focused on the “itoura” cutting land at the blade’s extreme cutting edge. This too requires zen-like focus and strict control over one’s inner badger to avoid wearing notches into the ura’s side lands.

Move the blade in two directions at the same time: Mostly to and fro in line with the cutting edge; but also on and off the stone’s edge perpendicular to the cutting edge. This will help avoid wearing notches into the side lands, and produce a stronger cutting edge (IMO).

Keep the stone flat and reverse it frequently to ensure even wear and less wasted stone.

Concentrate your senses and develop hand-soul coordination : You are a leaf on the wind; Watch how you soar (Hoban “Wash” Washburne in Serenity). I hope you have better luck than Wash did…

In the case of chisels, I hold the handle in the palm of my right hand and place thumb and forefinger on opposite sides of the neck/shoulders pinching it between them. I place the tips of the fingers of my left hand on the bevel, and move right and left hand together. And as in the case of plane blades, I move the blade both forward and backwards and left to right at the same time.

Give it a try. What do you have to loose?

In the next post in this series on sharpening, we will look at which direction to sharpen. Few give this matter any thought, but most should.

YMHOS

If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.

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Previous Posts in the Sharpening Series

Sharpening Part 20 – Flattening and Polishing the Ura

Shall I compare thee to a summer’s day?
Thou art more lovely and more temperate:
Rough winds do shake the darling buds of May,
And summer’s lease hath all too short a date;
Sometime too hot the eye of heaven shines,
And often is his gold complexion dimm’d;
And every fair from fair sometime declines,
By chance or nature’s changing course untrimm’d;
But thy eternal summer shall not fade,
Nor lose possession of that fair thou ow’st;
Nor shall death brag thou wander’st in his shade,
When in eternal lines to time thou grow’st:
So long as men can breathe or eyes can see,
So long lives this, and this gives life to thee.
William Shakespeare, Sonnet 18

Your most humble and obedient servant began this post with the elegant sonnet quoted above, indisputably one of the most beautiful pieces of poetry ever written in the English language, instead of the usual pithy proverbs of Red Green, that towering Canadian Philosopher-Handyman and erudite Leader of Possum Lodge, just to show Gentle Readers how refined we at C&S Tools can be when no one is watching (ツ). But sadly we must now pause all such elegant distractions for a time to focus on the nuts-and-bolts of how to true the ura of a Japanese woodworking blade, the first step in making it sharp.

This tutorial is rather wordy because Beloved Customers sometimes find the task of managing the ura difficult at first. Indeed, while truing the ura of Japanese chisels and planes is a simple task, it’s one many get wrong the first time, occasionally resulting in emotional damage to both blade and it’s owner. I know it almost drove me non compos mentis the first few times I tried, but now that my psychiatric team has stumbled onto the right mix of meds, and Doctor Alonzo has released your humble servant from that unflattering canvas straight jacket, Beloved Customers have the opportunity to learn from my mistakes. Rejoice!

This is the first article in the series where we actually turn steel to mud, so let’s get to it.

Important General Principles

All standard chisel blades and plane blades, whether Japanese or Western, need to have a planar “flat,” as it’s called in Western chisels or “ura,” in the case of Japanese chisels and planes opposite the bevel. When sharpening such blades it’s ideal for these areas be in contact with sharpening stones over their full width, and ideally, full length. Perfection is not necessary, however, so don’t let yourself become obsessive; That way lies madness.

A few lost souls mistakenly assume (just before they go barking mad) that the lands surrounding the hollow-ground uratsuki must be perfectly planar for the chisel to function, but such is not the case. Granted, it does make it easier to sharpen the blade, but it need not be achieved immediately, especially since a planar ura can be easily obtained gradually over multiple sharpening sessions.

If Beloved Customer’s chisel does not have a fully-planar set of lands surrounding the hollow-ground uratsuki when new, understand that it may be a hand-forged, hand-shaped, hand-sharpened tool with imperfections, and perhaps not a CAD-CAM designed, mass-produced, chisel-shaped, sharpened screwdriver. If so, please understand that this is not an aberration but is normal. However, if such natural irregularities distract to the point your eye starts twitching like that of Chief Inspector Dreyfus after spending time with Inspector Clouseau, perhaps hand-forged tools are not your cup of tea.

Procuring Perfect Tools

The previous sentence may seem to suggest that we at C&S Tools prefer to not provide our humble tools to perfectionists, but that is not the case. Rather, we insist Beloved Customers seeking the perfect chisel, plane, saw or knife adjust their expectations for perfection to match their expectations for financial outlay and fabrication time. What conditions? First, multiply your tool budget at least tenfold (seriously) and set aside that budgeted amount in hard cashy money, maybe in a thick roll in your sock drawer. You see, unlike your unworthy servant who many assume works for free, craftsmen with the skills required to produce perfect tools, and who are willing to invest their valuable time in doing so, are in high demand and do not work for free. If this seems steep, then perfection is not for you.

Next, plan your order carefully, and perhaps commission drawings. Not as easy as it sounds, mayhap.

Finally, steel yourself to wait a minimum of two years for the work to be completed, for you see, while many desire perfect tools and are willing to pay the price, you don’t need toes to count the number of overworked craftsmen that can actually forge them nowadays.

Oh yes, I almost forgot one thing. In the case of our Perfect Tool Blackmith, he has an unusual condition, one based on valid reasons I cannot disclose, that the recipient be a working professional craftsman, not an amateur, hobbyist or collector.

An option to having a perfect chisel custom-forged new is to seek out a genuine Hidari-no-Ichihiro chisel because the Yamazaki brother’s products, though very expensive back in the day and more expensive now, were pretty close to perfect in shape and appearance. But beware counterfeits.

On the other hand, the tools we sell to our regular Beloved Customers are extremely practical, they look OK, perform just as well as Perfect Tools, cost a helluvalot less, and most importantly they are waiting on our shelves right now quivering in anticipation of an airplane ride to new masters who will feed them oodles of yummy wood. So which do you think is is better? A perfect prima donna safe queen of a tool that takes years to procure and is too precious to use hard, or a reasonably-priced, hard-working, hand-forged, high-performance, eager but perhaps less than perfect tool you can have right away?

Working With the Imperfect Ura

In any case, please be aware that a chisel with an imperfect ura (nearly all of them have some problems when new) can be perfected over time and will work just fine as-is if you are patient, remain aware of the blades tendencies, and compensate using your eyes and hands accordingly. After all, the chisel only does what you direct it do, so please direct the blade instead of just going along for the ride while drinking adult beverages and smokin wacky-tabaccy in the back seat with Murphy. 〜(シ) 〜

If the plane formed by the ura’s lands is concave, the chisel will tend to undercut the end walls of a mortise, not difficult to avoid with some caution of the sort one must always exercise.

On the other hand (the one with 6 fingers) if the plane is convex, the chisel will tend to scoop away from the end walls of a mortise. All things considered, however, concave is far better than convex.

But whether concave or convex, such irregularities always exist to some degree from time to time in all chisels made by humans and sharpened by hand. It’s the craftsman’s job to manage his tools. Of course, this means we must strive to create and maintain a reasonably flat ura, so let’s consider some practical time-proven solutions that avoid wasting a lot of time, stone and steel, and at the same time don’t prematurely wear out the hollow-ground uratsuki in the process.

Let us begin by observing that the surface area (square millimeters) of the hard steel encompassed within the lands at the ura that we need to eventually make planar can be divided into four areas:

The land immediately adjacent and parallel to the cutting edge (aka “itoura”);

The land where the neck meets the blade, also kind sorta parallel to the cutting edge;

The two skinny side lands, (aka “ashi” meaning “leg”) are more-or-less parallel with the blade’s long axis and located on the right and left sides of the hollow-ground area called the uratsuki;

All four lands are necessary to the chisel’s function, but the one that matters most when sharpening and cutting is the last couple of millimeters at the itoura touching the cutting edge. Please make sure you understand this.

While some people fixate on it, the land near the neck matters least of the four.

The side lands are important bearing surfaces for aligning the chisel in the cut, but they are less important than the cutting edge land, the itoura. If you like your chisels and planes, prefer they remain as easy as possible to sharpen, and intend to use them for a long time, it’s important to understand that working the ura over-agressively on rough stones is the quickest way to wear the side lands down prematurely, thereby making the uratsuki shallower quicker, gradually defeating the subtle genius of the design of Japanese woodworking blades before their time. We want to maintain the ura as deep, long and wide as reasonably possible for as long as reasonably possible.

Allow me to explain this further. As we inevitably grind away on the skinny side lands they will become gradually wider while the hollow-ground uratsuki becomes gradually shallower, with the result that the amount of hard steel we must sharpen/polish will gradually increase, which is inconvenient in so many ways. Sadly, too many people make their chisel’s side lands fat as a sumo wrestler soon after purchasing a chisel in their anal-retentive quest for the totally flat ura. Makes me wanna cry.

The cost-efficient and time-efficient solution is to focus on the important itoura, and make small corrections to the ura’s three other lands over multiple sharpening sessions thereby saving valuable time as well as expensive stones and steel while preserving the ura as long as possible. How to do this? Focus all your attention on the most important area, the itoura, and patiently plan on accomplishing the job over 5~10 sharpening sessions, using the chisel between each sharpening session.

Don’t attempt to correct/polish the ura full-length from cutting edge to neck at first, instead work only the area behind the cutting edge on the stones (which must be flat). To do this, focus finger pressure nearest the cutting edge only. An effective approach is press down on the land nearest the cutting edge while moving the blade on the stones, while the rest of the blade hangs off the stone.

In other words, while pressing down with the fingertip(s) on the face of the blade (the surface opposite the ura with the brand on it) as near as possible to the cutting edge, move the last 5~15mm of the blade onto and off of the stone in a back-and-forth diagonal motion concentrating abrasion where it is needed most. This requires the ability to sense the balance of the blade on the stone, and to apply fingertip pressure where it is needed most. Wow, imagine that.. real hand skills.

If you don’t have these skills now, they are easy to develop with concentration and practice, but it doesn’t happen by accident, and if left unleashed and unmuzzled, your impatient, careless inner badger will try to make a mess of things.

During each subsequent sharpening session, increase the width of the area you work on the stones a tiny bit until the entire ura is flat and can be worked on the stones.

Through this technique and over multiple sharpening sessions, you will notice the ura’s lands will gradually become planar while only the lands nearest the cutting edge increase in width. Honest.

It helps to apply either marking pen ink or machinist’s blue to the blade to confirm whether or not you are applying pressure where it is need most and that abrasion is proceeding as desired.

It is human nature to want to rely on the flatness of the ura’s lands to keep the blade flat on the stone, and therefore we tend to apply pressure at the midpoint of the back so that the pressure on the ura’s land is even at all points of contact. This feels good; It feels stable.

But if you consider the narrow width (and small area) of the hard steel exposed at the side lands compared to the lands at the ito-ura cutting edge and the corners of the blade, you will see why this technique will wear the skinny side lands quickly and prematurely.

Allow me to restate an important point: The goal is to focus hand/finger pressure nearest the cutting with much less pressure focused on the sides lands thereby preserving them, and the depth of the ura, as long as possible. This technique will also save time and expensive steel. It is an advanced skill, but one Beloved Customer should aim to perfect.

Once the ura of your chisel is flat and true, you should not need to true it again unless the blade needs major repairs.

With much use, the itoura will dissapear, and the bevel must be tapped-out (“uradshi”) and the ura re-flattened (“uraoshi”) to restore it. I won’t delve into the subject of “tapping out” the ura of plane blades in this post but a detailed explanation can be found in Part 30 of this series.

A detailed example follows.

Evaluate the Ura

The first step in flattening or truing an ura is to evaluate its condition. Don’t start grinding away willy nilly without first checking it and making a plan. If you find you cannot stop yourself, don’t walk but run to the nearest pharmacy and buy a bucket of the medicine discussed in part 19 in this series about maintaining sharpening stones.

There are several ways to check the ura’s condition. A thin straightedge works well in most cases. A thick straightedge may be easier to keep stable on the ura, but it will shut out too much light making observation difficult. Place the straightedge edge-down on top of the full length of the side lands all the way to the cutting edge. Keep the straightedge touching the land; Don’t let it span the hollow-ground uratsuki. Hold the straightedge and blade up to a strong light source and look for light passing between them. This technique is quick and dirty and will suffice in most cases, but does not tell you a lot about twist.

Use a straightedge to check the right and left lands for flatness. It doesn’t do any good to span the hollow-ground urasuki, so don’t bother. These photos are taken from above for clarity, but you want to hold the blade and straightedge together up to a strong light to observe any light showing between them indicating a gap. I am using a small square, but a simple small straightedge is more convenient. This takes a bit of coordination so be careful not to drop a chisel on your toe. I’ve done this once or twice before. Monkey meet football.

This is a 30mm Sukemaru atsunomi, a famous brand and an excellent and powerful chisel hand-forged by Mr. Usui from Shirogami No.1 Steel. It’s in pretty good shape, but can benefit from a little truing as can most new chisels and plane blades.

Another method to check the ura for planar is to paint the shiny lands with dark marking pen ink or Dykem liquid, apply a tiny bit of fine sharpening stone mud to a piece of flat glass, like the piece mentioned in Part 17, and rub the blade’s flat or ura over the glass. The high spots will become obvious. If the ura is banana shaped (convex), mark the high spot with your marking pen. More often than not, the ura of chisels will be generally flat, but sometimes the last 2mm or so of the cutting edge will be curved upwards towards the chisel’s face.

I learned two things from my examination of this atsunomi. First, there is a high spot (convex) at the skinny land on one side located approximately 1/2 to 5/8 the blades’ distance from the cutting edge. The land on the other side seems a little low. Hmm, curious. This is a bit unusual, but it happens when a blade warps during heat treat, which Shirogami steels tends to do frequently.

The second problem I observed was that the last 3~4mm of the itoura land at the cutting edge curves downward away from the ura just a tiny bit, enough to cause problems.

I next must formulate a plan to resolve these problems with a minimum of time and effort and without making things worse.

Make a Plan

The temptation to start grinding away immediately will be powerful. But… I must… resist… the… stupidity impulse!!

If it becomes too much, I’ll take a coffee cup or three of the medicine mentioned in the previous post and slather it on my head forcefully. Don’t hold back, for Pete’s sake, rub it in really good now. Some say my excessive use of this medicine is why I am as bald as an egg, but I prefer to believe it is caused by the high-intensity psychic waves radiating from my gigantic brain (ツ). Thank goodness for my aluminum foil skull cap with its artfully protruding copper wires or the radiating light might blind airline pilots passing overhead!

But getting back to practical matters, a useful plan must have goals and objectives. In this case the goal is a perfectly planar ura, but if this goal is difficult to achieve quickly there is an objective you achieve immediately in any case, one that may make it possible to achieve the larger goal over multiple routine sharpening sessions without any special effort.

As I keep harping, to make a chisel or plane work well, you need a sharp, flat bevel and a sharp flat area right at the thin land (itoura) adjacent the cutting edge. This is where the cutting occurs and the area I need to keep sharp, so I will make creating this flat area the first objective in my plan, and then determine the steps to achieve it. I make certain every step in my plan and every stroke I make on the stones gets me closer to this objective, not further away. This means working smart, ruthlessly calming my inner badger (you know, that nearsighted, short-legged snuffling beast that just keeps digging) and repeatedly stomping my stupidity impulse into the ground. Frequent applications of idiot ointment help too.

If the blade is arched (concave), touching at two points, one near the neck of the chisel blade, or head of the plane blade, and at the other at the cutting edge, and not in between, all is well. I recommend you leave a blade like this as-is because after a few sharpening sessions the ura will become flat and twist-free without any special effort, and the blade will become very sharp and be entirely functional (assuming the faces of your stones are flat).

If the blade is wavy (rare) or banana-shaped (convex), your plan needs to take those details into account.

In this example I located the highest point of the bulging area at the ura and marked a line across it with my marking pen. I then measured halfway between this line and the cutting edge and made another line. which I will call the “focus line.” It is here where I need to focus the most pressure when grinding down the ura, NOT the entire length of the blade, despite what my inner badger demands.

The purpose of doing all this prissy planning and layout work is to protect the right and left side lands from being wasted unnecessarily. Newbies and those with poor badger control often insist on working the entire length of the blade on the stones, but this is illogical and ignores three points.

The first point often overlooked or ignored is that the majority of the metal I need to waste is usually located to the right and left of the itoura land nearest the cutting edge, not the full length of the blade, so there is little benefit to grinding the entire ura.

The second point is that the side lands are thin as a blade of grass and will abrade very quickly with almost no effort. Besides, without using large plates and stones, it is very difficult to work the blade’s full length accurately without wearing steps into the side lands anyway.

The third point often ignored is that it makes no sense at all to try to grind down the land nearest the neck since the plane of the ura hinges on this land anyway. Best to leave it alone and focus my efforts where they will make a useful improvement.

Plane blades don’t even have a land near the head, so the futility of working the entire ura on plane blades is even more obvious than for a chisel.

The left photo shows a line drawn at the highest point in the convex ura (bottom arrow), and another line halfway between it and the cutting edge (upper arrow). The second photo shows tape on the blade’s back with the high point line, and the halfway line, or “focus line” at the upper edge of the tape. Use these marks to ensure you have a plan and follow the plan without wasting too much valuable steel at the ura. Notice how narrow the right and left side lands are before we begin working the ura.

Work the Plan

The traditional Japanese tool used to flatten and/or correct ura is a smooth steel lapping plate called a kanaban, meaning “metal plate.” To use it, carborundum powder and water are placed on the plate, and the blade is lapped. This is not a difficult process at all, but there is a tendency for the blade’s perimeter to be ground more than the interior areas as the grit is forced in between the kanaban and the blade’s perimeter. To avoid this tendency, and to speed the process up, I prefer to use diamond plates or diamond stones instead of kanaban.

Whatever plan you developed, and whichever tool you selected for this job, the time has come to work the plan. Do you need more idiot-b-gone medicine? A bigger coffee cup?

First, color the ura’s perimeter lands with a marking pen or Dykem to help you see where the ura is being ground down. Don’t ever guess.

Place the most pressure on the focus line selected above. Move the blade back and forth (not side to side) onto and off of the diamond plate, diamond stone or kanaban with the cutting edge and the focus line always touching the diamond plate or kanaban. Don’t go past the high point for now. Be careful to not grind a notch into the narrow side lands where they meet the edge of the diamond plate or kanaban. Most people make this mistake at first. Please don’t you make it more than once.

Grind the ura down so the line at the highest point and the cutting edge is fairly flat.

Work the blade on and off the edge of the diamond plate using short strokes and without going much past the highest point marked earlier. This works because the right and left side lands are thin and can be abraded in just a few strokes. I have moved my fingers to reveal the lines, but in actuality my fingers will press down hard on the focus line while working the blade.

Using a stick to apply more pressure to the blade. I am holding the end of the stick and the chisel’s handle together in my right hand. This is simply illustrating a technique. This chisel did not actually require this sort of aggressive attention.

The same stick technique works even better for plane blades and makes it easier to apply pressure right behind the cutting edge. When doing this, however, be sure to work the blade both forward and backward while moving it right and left, on and off the plate’s edge to avoid digging a trench into the narrow side lands.

Remember, the narrow lands at the sides of the hollow-ground urasuki will abrade down quickly. And the rest of the ura can be gradually flattened during subsequent sharpening sessions using regular sharpening stones. It doesn’t need to be made perfect immediately. What matters most is the steel on the itoura land right at the cutting edge.

The high spot on the side land near the top of the photo has been relieved after just a few passes on the #400 diamond plate. The side lands are now both in fair condition, and the land behind the cutting edge (itoura) needs just a little more work.

After a few more passes on the diamond plate, the itoura is in good shape. Please observe that the side land at the bottom of the photo is not in full contact, but the opposite side is. This is will not impact the blade’s performance, and will work itself out during future sharpening sessions without special attention.

Flattening my stones before using them. Notice I am using two 1,000 grit stones to save time and stones. Don’t neglect flattening your stones, whether you use waterstones, novaculite stones, coticule, or even sandpaper.

Working the ura on the flat 1000 grit waterstone. Did I mention it is flat? Notice that I am working on and off the stone, not side to side, to save the right and left lands. Just a few strokes are required. I am now focusing pressure nearest the cutting edge. Some but not all strokes are full length. The goal is simply to remove the deep scratches on the itoura left by the diamond plate. All other deep scratches can be left alone for now and removed during future sharpening sessions a little at a time.

The ura after polishing on the flat 1000 grit waterstone. At this point the ura is in good shape. Notice how the land at the photo’s left is wider that elsewhere. This increase in width developed because this location was the high spot on this convex ura. Notice how the land on the right side is not even touching the plane in one area. What you should take away from this photo is the realization that if I had focused my efforts on this high location first and ignored the downward curvature of the land nearest the cutting edge, I would have wasted a lot more time and valuable metal only to shorten the useful life of this excellent chisel. Do you see the benefit of carefully checking the ura’s condition, making a plan with clear goals and objectives, and then working the plan? Did the medicine work? Next, we’ll work on the bevel, make a tiny burr, polish it off by making a few strokes alternating from bevel to ura, and be ready for the finishing stone.

Working the bevel on the flat 1,000 grit waterstone. Notice the mud piling up in front of the blade indicating the extreme cutting edge is in contact with the stone. I am applying pressure only on the push stroke to prevent the stone from rocking and developing a “bulging bevel,” A honing jig is not necessary.

The bevel after working on the 1,000 grit waterstone. No jigs were used. No “tricks” involving rulers were used. A silly, inefficient “micro-bevel” was neither wanted nor needed. The bevel is perfectly flat. Flattening the ura and polishing both ura and bevel to this level took less than ten minutes. When the purchaser of this blade eventually dulls the edge, he should not need to spend more than 2~3 minutes to sharpen it once his gear is ready, assuming he is able to sharpen freehand.

This flattening process is seldom required except on new blades.

Polish a blade’s ura up to the level of your finest finishing stone once, and don’t touch it with rougher stones again unless it is absolutely necessary, or further gradual flattening is required. This means that in normal sharpening sessions you must remove all the damage at the cutting edge by abrading the bevel with the rougher stones, and only when the bevel is ready for the finish stone, do you work on the flat or ura, alternating from bevel to flat/ura until all defects, burrs, and even visible scratches are polished away.

If you condition the flat (ura) side of the blade correctly, and keep it polished, you should not need to work it on anything but your finish stone until it is time to tap out and grind the ura or back in the case of plane blades. Therefore, the bevel side of the blade is where we spend most of our time and effort.

Now that the ura is in good shape, we will look at sharpening the other side of the wedge, the blade’s bevel, in the next post in the series. In the meantime, keep yer stick on the ice.

YMHOS

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Sharpening Part 19 – Maintaining Sharpening Stones

砥石の面直しについて：鑿研ぎ練習番外編_e0248405_17182931.jpg

Give me six hours to chop down a tree and I will spend the first four sharpening the axe.
Abraham Lincoln

Sharpening stones must be maintained if they are to perform effectively. Abe Lincoln’s quote above is especially relevant to this subject.

There is a lot of hogwash taught as holy gospel on this subject, so in this article your humble servant will suggest some more or less traditional methods that both work well, and are cost-effective. Do with them as you will.

Key Principles

Let’s begin with a few basic but critical principles about sharpening that Beloved Customer should understand and use:

For the majority, but not all, applications, your blades need to meet the following standards:
- Flat back/ura: perfection is not necessary but it must be flat enough for you to be able to consistently polish the last few millimeters of steel at the ito-ura (flat adjacent the cutting edge) on your finishing stone;
- Flat bevel, for the same reason mentioned above;
- Straight cutting edge (except when a curved cutting edge is required).
All Stones get out of tolerance with use. Working a steel blade on a sharpening stone of any kind, whether waterstone, novaculite, coticule or carborundum, wears the stone a little bit with each stroke, creating a dished-out, twisted surface to one degree or another, even if you can’t detect the distortion with Mark-1 eyeball. Therefore, you need to develop the habit of frequently checking the flatness of your stones when in use and truing them when necessary;
Despite what many imagine, a hollowed-out stone cannot reliably maintain a blade with a planar ura, a flat bevel, and a straight cutting edge, but it can damage the blade being sharpened.

The Rule of Seven applies, so reread these three critical points three times, click your heels three times, and ask the gods of handsaws to help you remember them.

Pretty simple stuff, right? I apologize if Beloved Customer already knows these things, but you would be surprised how many people know them but still ignore them, and then wonder why their blades won’t behave. Iron Pixies? Nah. Perhaps Mifune Toshiro said it best in Akira Kurosawa’s movie Yojimbo when he quoted the old Japanese proverb: “There’s no medicinal cure for foolishness” (馬鹿に付ける薬はない).

Toshirô Mifune in Yôjinbô (1961) — A scene from Akira Kurosawa’s classic movie Yojimbo (1961), the inspiration for the later spaghetti westerns beginning in 1964 and even the more recent TV show The Mandalorian. In this scene, the nameless loner anti-hero is warning off some hired ruffians who have bragged about their judicial tattoos, and the death sentences hanging over their heads, and informed him they aren’t afraid of him or the pain of being cut. The hero responds with the proverb “There’s no medicine for a fool,” then tests their resolve by cutting 3 of them. Ouchy! A hard lesson easily avoided. BTW, if you have tattoos and visit Japan, best to keep them covered since they have an old and indelible association with criminal organizations and judicial branding. On the other hand, if you enjoy being mistaken for a lowlife, violent, thieving piece of scum, by all means show off your ink.

Here’s the scene on YouTube. Please don’t watch it if you are squeamish. Never call the Man With No Name’s bluff.

Yôjinbô (1961) — The Man With No Name (aka Kawabatake Sanjuro played by Mifune Toshiro) pondering the interesting financial opportunities awaiting him in the troubled little post town. His older swordsmith friend (Tono Eijiro) bitterly objects to his plans. The old boy was right.

Although it has only happened once or twice in my recollection (my saintly wife of the jaundiced eye may disagree (ツ)), on those few occasions when I have made a stupid mistake I have been known to ask subordinates to fetch a large bucket of “Idiot Salve” for me from the drugstore. The jury is still out on the effectiveness of this ointment, but I would like some credit for writing this entire article without applying any.

But I digress.

Obviously, if every stroke wears the stone a little, then we must constantly check our stones with a stainless steel straightedge for flatness (length and width) and wind (diagonals) as we use them. It takes 3 seconds. Even if your stones are brand new, you may find distortions. Time spent checking is not wasted if it results in improvement, which it usually does. This is the heart of quality control, and is applicable to everything in life.

Truing Stones

When your check reveals the stone is out of tolerance, you need to flatten/true it. Don’t put it off.

There are many ways to get this job done. Some people advocate using diamond plates to flatten stones. Others insist that sandpaper is best. And then there are the specialty flattening stones. It ain’t rocket surgery. All these methods work, but are unnecessarily costly and time consuming in my humble opinion. The following is the procedure I use. I know it sounds weird. I didn’t invent it but I’ve used it for many decades and highly recommend it. Give it a try, Beloved Customer, before you dismiss it.

Always have two of each of your rougher stones soaked and ready to go when you start sharpening, space and weight permitting. This means 2 – 1,000 grit stones, and 2 – 2,000 grit stones in my case. If you use your tools, owning these extra stones is never wasted money and can improve your efficiency. For instance, beginning the day with two flat 1000 grit stones (the grit your humble servant uses the most) ready to rock n roll means I have 4 flat faces to use before I absolutely must stop work and true them.

If the blade is damaged, for instance chipped or dinged, begin with a rougher stone or diamond plate, whatever you have that will waste metal quickly and easily while keeping the blade’s bevel flat. Don’t waste time frikin around with medium-grit stones when steel must be removed.

If your blade is not damaged, begin the sharpening process with a fresh, flat stone, for instance 1,000 grit if the blade is fairly dull, or 2,000 grit if it’s just partway to dull. Turn the stone end-for-end halfway through the estimated number of required strokes and continue sharpening. This is important to keep your stones true. Yes, you need to keep track of your strokes, at least approximately. This will become second nature with practice.

Occasionally check the stone for dishing and wind using your thin stainless steel straightedge. With practice you will develop a sense of the stone’s condition without the need to use a straightedge, but check each stone frequently while you’re developing your advanced sharpening skills. Stop using the stone when the distortion becomes noticeable.

Switch the distorted stone with your flat stone of the same grit and continue sharpening.

When both stones of the same grit become distorted to the same degree, cross-hatch the faces of both with a carpenter’s pencil, then rub them against each other under running water if possible, or while frequently adding water if running water is not available. Take short strokes and be careful to apply even pressure to the stones. This requires self-control, switching the stones end for end frequently, and making an effort to apply even pressure with your hands, and is more difficult than it sounds until you get used to doing it. The friction and water will wear the high spots down, I promise.

Monitor the pencil marks to track progress.

Check with a straightedge frequently, and stop when both stones are flat, or maybe even a tiny bit convex.

With practice, and if you don’t let your stone’s condition get out of hand, this process should take only a few seconds, but it will ensure you are always working on flat stones.

If you think this technique is slower than using a diamond plate, specialty flattening stone, or sandpaper, you may be overlooking a key point, namely, that using this method one can flatten the faces of two stones at the same time, in the same time period, and with the same hand movements. It may be slower than flattening a single stone with a diamond plate, but it is definitely quicker than using the same diamond plate to true two stones one at a time. Think about it.

It’s also cheaper because diamond plates are costly, and wear out. The specialty flattening stones are not cheap, and they too wear out. Both methods can contaminate stones, in my experience. And sandpaper sheds the most contaminating grit, and is the most expensive method long-term. No-brainer.

Now you have two stones of the same grit on-hand that are flat, free of contamination, and ready to rock-n-roll without wasting time or money on diamond plates, sandpaper, or special flattening tools. These are four fresh, flat surfaces to use before you need to take time away from your paying job. And if you pay attention when sharpening, and take care to use each stone’s entire face, the time between sharpening sessions can be increased while saving significant amounts of cashy money.

Truing Stones Using a Glass Lapping Plate

Finishing stones seldom require flattening, but the same procedure can be used when necessary. A better solution is to the use the float-glass lapping plate described next.

If you need to get a stone extra flat, rub the stone on the ⅜~1/2” (9~12mm) or thicker plate glass mentioned in the previous post. You can often bum scrap pieces of suitable glass from glass stores or contractors. Dumpster diving behind a glazing shop may prove useful if you are careful and don’t cut your arm off. Don’t forget to remove the sharp corners and edges with a carborundum stone or you might end up like the annoying guy in the video linked to above.

To turn the plate glass into a lapping plate, aggressively roughen one side with a carborundum stone or diamond plate, and clean it thoroughly using a scrub brush, soap and running water to remove every trace of glass and stone particles. Then clean your brush and scrub the glass again.

The scratches you just made will turn it into an inexpensive and efficient lapping plate. Trust me. Just wet the glass and rub the stone on it while rinsing frequently. Try to use the entire surface of the plate, not just the center. And be sure to apply uniform pressure to the stone.

If a stone becomes grossly distorted, you can use a rougher stone or diamond plate to true it. Even a concrete sidewalk and garden hose will do the job. However, if you do this, remember that there is no way to avoid contaminating the finer stone with embedded grit from the rougher stone or concrete. This embedded grit must be dealt with before using the stone.

To remove the offending stone particles, scrub the stone’s faces, sides and ends with a rough bristle brush under running water. Finish by polishing the stone’s face with a nagura stone, and rinsing well.

You should also use your nagura stone frequently to dress and true the faces of your finishing stones.

And for Pete’s sake, don’t forget to maintain the edge chamfers on your stones and keep them free of contamination and pixies too.

As with all things, moderation is best. It can be be time-consuming and expensive to keep one’s sharpening stones perfectly flat, but perfect stones are not especially better for general woodworking than a pretty-flat stone.

Beware! For the rabbit-hole of perfect flatness is dark and deep, and sleepless nights and gibbering insanity afflict many who strive to plumb its furthest depths.

Rough Stone vs. Finer Stone

Here is an important factoid you should remember: A stone trued using a rougher stone or diamond plate will be effectively of rougher grit than its designation until its surface is worn smooth again. And it will wear faster too. But if you use identical grit stones (same brand is best) to true each other, the effective grit of each will remain unchanged.

Reread the last paragraph three times, click your heels three times, and do that prayer thing again. Namu Amida Butsu.

Conclusion

It’s important to keep ones’ stones flat and free of wind, and it’s not difficult or time-consuming to accomplish. In this article we looked at inexpensive traditional ways to effectively flatten and maintain our sharpening stones long-term. Give them a try.

Now that our stones are looking good, in the next post in this series of hogwash refutation we will be ready to consider how to use them to flatten and polish the ura of our blades. Y’all come back now y’hear.

YMHOS

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Sharpening Japanese Woodworking Tools Part 1

Sharpening Part 17 – Gear

Do what you can, with what you have, where you are.
Theodore Roosevelt

Sharpening can be a stuff-intensive process, and since portability is always a factor in your humble servant’s case, I strive to reduce the number of accouterments to the barest minimum. The following is a list of some gear, besides sharpening stones, that I am confident will prove useful whether in Beloved Customer’s workshop or the jobsite.

I will first list the gear needed for general sharpening either in the workshop or the field. At the end of this article that I have listed a minimal set of gear for use specifically in the field where space and weight might make it inconvenient to carry the heavier/bulkier general set of sharpening gear.

A General Set of Sharpening Gear

The following is a list of tools and equipment I think are indispensable for sharpening Japanese woodworking tools in general and in many, but not all, circumstances. I have not included some tools that may be necessary for doing “uradashi,” i.e. “tapping out” the hollow-ground urasuki of Japanese plane blades. So here we go.

Sharpening Stones
Stone Base or Holder: A wooden base with a wedge to secure stones is the old standby for supporting sharpening stones above the benchtop or ground, but repeated wetting and drying and the resulting expansion and contraction may compromise a wooden base over time. For my synthetic stones I have come to prefer the commercial bases with twin metal rods and rubber feet. They are unromantic, but are durable, stable, non-slip, grip the stone tightly without breaking it, and work well anywhere. If you decide to make and use a wooden base, I highly recommend Ipe wood because it is stable, unaffected by water, won’t rot, and bugs hate it.

Washing powder storage square plastic buckets in 2L 5L 8L 10L 15L 18L 20L

2. Soaking bucket for stones: A medium size plastic or steel mop bucket (not the heavy industrial unit with rollers) is best for soaking stones because they are durable, and their more or less square/rectangular shape is superior to round buckets for leaning stones on end against the inside walls. You don’t want to stack the stones on top of each other if you can avoid it. Any durable bucket that doesn’t leak will work, but a tightly-fitting lid is a big advantage. You will need to soak all but your diamond plate and finishing stones in this bucket before each use.

I soak my synthetic stones 365 days a year. I close the lid to prevent evaporation and to keep out mosquitoes and woke zombies, and add either washing soda, borax or a few drops of Simple Green ProD5 concentrate to the water to prevent bugs and algae from growing when I won’t be using the stones for a while. Simple Green is a better bug/algae killer, but Borax has the advantage of making the water slightly alkali which helps prevent rust in my blades during sharpening.

Some stones use a magnesium-based binder that can dissolve and weaken them if left soaking for long periods of time. Please refer to the manufacturer’s instructions.

3. Glass Plate: 9mm~12mm thick piece of float glass. This is used to true the faces of waterstones when they become distorted through use. My current plate is 600mm x 300mm x 10mm, a bit on the small size. Beside truing waterstones it is useful for many other purposes including checking the fettle of your plane’s soles. I won’t tell the heartbreaking tale of what happened to the last one I took into the field, but rest assured I leave it in the workshop now. We will discuss how to use this tool in future posts in this series, God willing and the creek don’t rise.

4. Working Surface: If working outside, a Japanese craftsman will place his stone holder directly on the ground or a concrete slab. A craftsman that works inside a shop will often have a wooden or plastic box with a board spanning the narrowest dimension forming a bridge. The stone rests on this bridge, often with a wet towel between board and stone to prevent slipping. This box, called a pond, catches water and mud dripping from the stones. The ideal situation is a board spanning a sink with a faucet of running water. When away from the workshop, I prefer to place a piece of fiberglass-reinforced rubber (EPDM) roofing membrane on a truck’s tailgate or stack of boards or gypboard at a jobsite. I can roll-up this lightweight, tough, and absolutely waterproof mat and stuff it into my toolbox for easy transport. In my workshop, I use a large plastic cutting mat placed on my workbench, but any waterproof non-slip surface will work. No need to get fancy. My stones and sharpening gear are stored under my workbench close at hand.

5. Water Source: While sharpening, you will frequently need water to wet your stones and rinse blades. If you work at a sink, use the faucet. If you work outside, a garden hose works great. Some people, mostly knife sharpeners who seldom use stones finer than medium grit, will scoop water from their pond or bucket to wet their stones. However, since stone slurry drips into the pond, this water will always contaminate stones with the grit from rougher stones, making it difficult to remove all the scratches left by the previous stone. To avoid this contamination, always use clean water for wetting and rinsing.

Some people prefer a spray bottle to add water, but spray bottles wet things I prefer to keep dry, so a better choice, in my humble opinion, is a plastic bottle such as a dishwashing soap bottle or a plastic lab wash bottle with a bent tube coming out the top. Almost any plastic squeeze bottle will work.

Tap water contains chlorine in all but backward countries, and chlorine accumulates and accelerates rust, so I use distilled water in my wash bottle, and add washing soda or borax to adjust the water’s PH, a technique I learned from sword sharpeners.

Some people add just a bit of liquid lye to their water to adjust the PH. This chemical can be purchased from industrial cleaning supply companies. Too much will damage your skin, so be careful. Also good for keeping Iron Pixies in the shadows.

6. Sharpening Station and/or Sharpening Pond: I don’t use a sharpening pond, and don’t believe them to be essential, but several practical options are illustrated below.

余暇のある時や休日だけに出現するものであるにせよ、専用の研ぎ場があるというのは工作をするものにとって幸せなことです。自分なりに工夫を重ねながら研究を深めてゆくのは、何よりも楽しみを感じさせてくれるでしょう。 — A bridge placed over a sink forms the ideal sharpening station. Professional workshops frequently use this classic arrangement. Flush the drain well. You may need to remove the sink’s P trap and clean sharpening stone mud out of it annually.

Plastic boxes placed inside a wooden box make a portable sharpening pond and stone storage box. There are dozens of variations on this theme possible.

7. Stainless steel straightedge: Use this to check stones for flatness and wind, and cutting edges for straightness. Don’t use a plain steel one unless you want to give the iron pixies skulking under your workbench great joy. The thinner the better. The thick blades used in combo squares are difficult to use in less than ideal light

8. Wiping materials: You will need something to clean and dry your blades during sharpening sessions. Rags work well for wiping and drying blades, and can be washed and reused, but be careful to avoid cross-contamination. Paper towels are most effective and convenient in my experience, but they cost money and make garbage. Decisions, decisions…

The traditional Japanese “Baby Turtle” brush with coconut husk fiber bristles.

9. Scrub brush: A clean stone is a happy stone, as are bases, buckets and glass plates, all of which have grooves and scratches and holes where grit can hide. Scrub brushes are great for digging out this contaminating grit. Coconut palm fiber brushes are ideal because the bristles are fine and grit does not get embedded into the bristles as much as plastic brushes.

The Lie-Nielson Honing Guide. An excellent if expensive tool.

10. Honing Guide: This tool is optional. I hesitate to recommend these jigs because they can easily become a crutch preventing Beloved Customer from becoming proficient at freehand sharpening. However, these types of jigs make it much easier and quicker to shape blades to the desired angle on rough stones, especially when correcting a double-bevel or bulging bevel to a more useful single, flat bevel. Eclipse-style honing guides work well. The die-cast versions are inexpensive. Lie-Nielson makes a terribly expensive version machined from stainless steel that I am fond of. Jigs won’t work for all blades, but it is worth having one.

tzushimanagura8_4 — A Tsushima Nagura Stone

11. Nagura Stone: More details will be included in next post in this series.

12. Bevel Angle Gauge: I’ve mentioned this tool in previous articles in this series, but list it here because it is critical. Use it to check the bevel angles of your chisels and planes during every sharpening session to ensure they don’t become too low weakening your cutting edges and inviting premature chipping. It can be made of any material that resists corrosion such as plastic, aluminum, stainless steel, or brass, my favorite because brass repels pernicious pixies.

Richard Kell bevel gauge — *A compact and effective brass bevel angle gauge by Richard Kell*

Minimal Set of Sharpening Gear

Sometimes, especially when working at remote jobsites, weight and/or space may impose physical limits on the tools we can carry with us. The following is a list of the minimal set of sharpening tools I bring in these situations.

1. Sharpening Stones

2. Stone Base: At the jobsite the stability this tool provides becomes more critical than ever, but if an ultra-light set of tools is needed, then it can be eliminated by placing the stone directly on a rubber sheet.

3. Soaking Container: There are many potential solutions for soaking stones in a minimalist or ultra-light situation, but I will describe just a few here. If clean water is available at the jobsite (water coming from a newly-installed pre-flush plumbing system may not be clean, and immediately post-flush it may contain lots of chlorine used to sterilize the pipes and fittings), then the minimalist solution I employ is to use a dry plastic bucket to carry tools, including sharpening gear, to and from the jobsite. I then add water to one bucket in the morning. Another option is to scrounge a joint compound bucket or paint bucket and leave it at the jobsite. But unless I have a gang box or other trustworthy tool lockup available at the jobsite, I still may need to transport at least one wet sharpening stone to and from the jobsite each day. The ultra-light solution I sometimes employ is to carry my waterstone(s) in a durable plastic container with a watertight lid, such as the thinner (6cm) rectangular containers by Tupperware. Water can be added at the jobsite to keep the stone(s) soaked and ready to rock-n-roll. And with the lid closed, dirt and dust can’t get in. An even lighter option is a heavy plastic bag. I place the stone(s) in the bag and carry it in my tool bag. At the jobsite, I can add water and close the bag with a thick rubber band to soak the stone(s). But be forewarned that these bags will not protect the stones, and the stones will make holes in the bag at the worst possible time.

4. Working Surface: I use the fiberglass-reinforced rubber roofing membrane described above. Tough and absolutely waterproof, it also works great for sitting on and even spreading out one’s lunch at the jobsite when more refined facilities and servants are unavailable (ツ).

5. Water Source: Clean water is necessary even in the field to wet the stones and to wash mud off tools. To save space, I use a small plastic squeeze bottle with a tightly closing lid that originally contained ketchup. If clean water is available at the jobsite, I carry it in my toolbag empty.

6. Stainless Steel Straightedge: See Item 7 above. I use a thin, flexible, lightweight one in the field.

7. Wiping Materials: A clean cotton rag and a some folded paper towels work well.

8. Scrub Brush: I always bring my “Baby Turtle” scrub brush. It’s lighter in weight than a plastic brush and comes in handy for tasks beyond sharpening too.

9. Nagura Stone: Just in case I need to get an extra-fine finish.

10. Brass Bevel Angle Gauge (on a red string around my neck)

The selection of stones I use at the jobsite will depend on the work planned for that particular day, but the minimal set is a 400 grit diamond plate/stone, a 1,000 grit synthetic waterstone, and a 6,000 or 8,000 grit synthetic finishing stone. If I anticipate a lot of sharpening, and if weight is not critical, I will bring two 1,000 grit stones to ensure I have 4 flat sharpening surfaces ready to rock-n-roll first thing thereby reducing the need to spend time flattening stones at work. I can also use them to flatten each other. If I need to do some fine finish planing, such as when doing door modifications/installations, I will bring a 10,000 grit synthetic waterstone. And of course I always carry a Tsushima Black Nagura stone.

In the next post in this romantic series of adventures in sharpening will focus on the important Nagura stone. Stay tuned for muscled thews and busted bodices!

YMHOS

If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.

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Go back

Paying Debts

Removing Damage and Correcting the Bevel

Normal Sharpening Procedures

Conclusion

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Raise a Burr

Testing the Burr

Transitioning From One Stone to the Next

Summary

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Money Down the Drain

Developing Good Habits

Hang Ten

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The Taming of the Skew

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Festina Lente

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Which Direction?

Training Techniques

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Stances

Get a Grip

The Gorilla Grip

The Three-finger Grip

The Three-finger Monkey Grip

Chisel Grip

Polishing the Ura

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Important General Principles

Procuring Perfect Tools

Working With the Imperfect Ura

Evaluate the Ura

Make a Plan

Work the Plan

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Key Principles

Truing Stones

Truing Stones Using a Glass Lapping Plate

Rough Stone vs. Finer Stone

Conclusion

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A General Set of Sharpening Gear

Minimal Set of Sharpening Gear

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