Evenfall Woodworks

When it comes to sharpening, abrasives are abrasives the world around. All paths are means that will lead to a similar end. Waterstones, oilstones, sandpaper, etc. The steel does not care; the abrasives don’t care either, as long as the grit equivilents of abrasiveness are appropriate to the goal. Sharpness. For the sake of this discussion, I am referring to the abrasive grits, as they correspond to the grits common to waterstones. I do this simply for the reason that waterstones are very popular, but I am in no way advocating that waterstones are the best abrasive. Most all abrasives will sharpen, and it is up to the end user to investigate the pros and cons of the various abrasives to determine the best paths for themselves. For cross-reference please refer to this cross reference chart to derive the equivilent grit for the media you choose.

It is important to keep in mind that the goal of sharpness has stages.

Coarse grits are for grinding, heavy material removal, bevel forming, flattening. Initial flattening and bevel angle forming are the biggest jobs and to aid getting the job over with, the coarsest grits should be used to get the bulk of these tasks done.

Fine grits are for honing and polishing. Removing coarse scratches in steel with finer ones is what creates finer sharpness. Creating the wire or feather edge needed to establish a fresh edge on the tool can be done with any of the grits.

It is up to the sharpener to determine how dull the tool is, and select the coarsnees or fineness of grit needed to restore the edge to sharpmess, fastest way. This means, it comes down to how much steel needs to be removed to form the wire, or feather. If only a lttle honing is needed to restore the edge, don’t select coarse abrasives when you begin. If a lot of honing is needed, don’t select fine abrasives when you begin, but know you will have to polish all the way up through the grits to the fine abrasives to restore the sharpness.

It is important to get a feel for the finish your honing equipment will give you as a finish result at each stage of the work. It will aid you to learn to evaluate what is needed, where to start, how long to hone, and when you have reached what was needed. Knowing this simplifies the task and helps you save time. This is learned by using the sharpening tools you have on your edge tools. It is getting to know one another, sharpening intimacy.

Flattening the back really only means that you only need a planar surface near the location where the bevel is, and the width of flatness on the back, or in other words how far away from the edge on the backside need be no wider than the bevel is, but you are welcome to flatten more of the back if you like, because sometimes it is easier to hold the tool on a wider surface. Flattening doesn’t have to kill you or be drudgery, just buy a Kanaban plate and some silicon carbide grit or diamond paste and get it over with. There are a number of places that sell those items, so in all fairness to them, please use a search engine for pricing. That is the fast track to flat backs. It is more important for backs to be a planar surface, flat, than it is to have a mirror finish, but the mirror finish is what we often wind up with eventually anyway.

The bevel side too, the bevel’s actual surface, is a narrow flattened plane. It is the intersection of these two planes where the angle forms. The flatness of these two planes are what help them succeed as very sharp, at the angle point. In fact it is difficult, maybe impossible to achieve a high degree of sharpness if this planar-flat surface isn’t present on each surface that makes up the bevel. Just like you would hone both sides of a knife to restore its edge, It just happens that on edge tools, the back makes up half of the beveled edge. It is the straightness of these two planes which form a line along the intersection of these flattened and honed surfaces, and that makes this edge.

Guides are useful for grinding specific angles. Please feel free to use them for the heavy work. Honing and polishing are something often done quicker, which is more useful and easy if you can learn to do it free hand. Free handed, the side sharpening method is likely the easiest to learn and use. The steel does not care, the wood does not either. If you cannot do this well enough, please, feel free too use the honing guide.

Forming a wire or feather only means you have ground, honed or polished past the dullness, depending on how long you allowed things to dull. It means you can now stop grinding and start honing and polishing.

Honing up through the finer grits is how we remove the wire edge created by honing past the dullness. If you hone and do not create this wire or feather, then you have not honed past the dullness. The dullness is the wear on the edge that you want to remove. The wire edge is what you want. Once you have achieved this all the way across the edge, you can then begin working both sides of the bevel with the grits appropriate to the level they are currently polished, alternately, to hone the edge to working fineness.

When honing off the wire, always hone the backs of the tool with the finest grit you have previously honed the back with. It means alternating stones from the bevel to the back, but why scratch up the back if it is polished?

If you examine your backs and bevels after honing to a mirror finish and see a glint of light right at the angle point, that is a flaw in your work. It should be a complete surface with no glints of light sparkling at you, especially from the bevel angle point. Glints of light indicate dullness.

In most steels, once you have honed through the grits to the 8000 grit stone, you have sharpened fine enough to pare end grain pine. End grain pine is the most difficult wood to pare without crushing; it really is the toughest task an edge tool for use in wood will ever see. **(Japanese tools often use finer steels and traditionally were used in softer woods, so there may be some benefit in honing good Japanese steels slightly finer if for use in soft woods)**

There are no recognized tests of, or charts with “scales of sharpness”. The time honored test for sharpness has been and always been; if the edge is sharp enough to do the required work in the material required, to the level of result desired, then sharp was sharp enough. The only major corollary to this adage is concerning edge-wear. Can the sharpness last a reasonable quantity of time, so as to bolster productivity? The results in the work have always sufficed, and learning what is needed so as to make results repeatable has been established.

You do not have to shave hair. Many people contend hair popping sharpness is an adequate test for sharpness. It isn’t. Hair is not wood, and hair is not an adequate test for pairing wood. I can shave hair with knives coming off 1000 grit abrasives. Since this is true, what if you can shave hair, so you stop honing well before you are sharp enough to do the work you need to? I was able to accomplish hair popping sharpness with spit on carborundum stones as a young kid, so I am not personally impressed with hair popping sharpness. This is a long way from the sharpness we need to push a blade through end grain pine with least effort, so as to pare it. I am saying, we are aiming for and achieving a much higher level of sharpness. If you have sharpened to 8000, you are well past the sharpness needed to shave hair. (Read this as, being able to shave hair can fool you)

If you visually examine the edge and see no glints of light reflecting from your edge, and you have polished to the 8000 grit level, no tests are necessary. At 8000 and after a little stropping on leather, the tool is as sharp as you will ever need, I assure you. Honing beyond here is a lot of work spent honing with a diminished work time in wood. In other word, the honing takes longer than the dulling does in this range. You can strop on leather with a little honing compound if you like for a slightly finer edge, which is sometimes temporarily helpful in softwoods. Again, if you feel the need to test, the pine is fine.

Much is written about sharpening, and I encourage you to study this subject, but this is most of what you really need to know. It isn’t rocket surgery. Once you get the heavy work done, (flattening and bevel shaping) it is done forever, and “maintaining” sharpness should generally take no more than 30 strokes on any stone. This means, don’t let your tools get too dull before you touch them up. You can easily do this as you work. It can take less time if you become a fastidious maintainer. If you have to rebuild edges every time you sharpen, then you have likely waited too long, and that is a lot more work than 30 strokes of maintainence sharpening.