Sharpening grafting knives

Of all the knives I have listed above, none of them come close to the high speed steel mill blade in its ability to hold a razor sharp edge.
No matter how I sharpen the other knives, they never become as sharp as the mill blade. And it stays sharp.
What I understand is that high speed steel was developed to cut other steel. Wood is no challenge for it. Sharpening it is a challenge .as it is so hard.
I hear there are even some better alloys available , but expensive , and don’t know a affordable source .i find these mill blades affordable .
I think any of the above knives and others, properly sharpened , are way better than a razor box cutter, and will improve your success .
Since it is to cold to graft, I am honing my sharpening skills, and getting ready to cut stuff.
My rule is: if you cannot shave hair off your arm with your knife, it’s not sharp enough for grafting.

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Hello,

How do i know what stone have the highes grit?

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The white stone is new and have grit 6000

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I write the grits on the side of my Japanese stones with a sharpe marker.

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The smoother they are the higher the grit, and the finer and slower the sharpening.

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Sorry to resurrect an old thread, but getting prepared for grafting season.

@cckw and @Olpea, at what angle do you like to sharpen your grafting knife? Are you saying the very edge should be 45 degrees? That seems like a blunt angle but I’m no expert.

I was practicing sharpening an old dull single beveled pocket knife I found in a drawer before hitting my new victorinox. I got the edge to a shaving sharp 16 degree angle (which was the narrowest angle I could achieve with the geometry of my sharpener). I rolled the edge after a couple test cuts - so either the steel is not good or the angle is too fine. When comparing the bevel vs the factory bevel on the victorinox it looks almost twice as wide, so a much steeper angle apparently…

It is an old thread. From when I first started it, it will be 6 yrs old in April of this year.

I still like the Lansky system for me. It holds the edge at a rigid angle. I can get even the worst stainless steel at a razor edge, with a finish strop on leather.

In terms of the angle, the Lansky system offers a few angles. Nothing near 45 degrees though. That’s too steep, even for a single bevel. I use around the 20 degree angle.

I wouldn’t pay any attention to the original Victorinox bevel. Those are super cheap grafting knives. Sharpen it to suit your style for grafting.

Honestly though, I’m moved past grafting knives for the spring grafting of apples and pears. I occasionally spring graft peaches, but fall budding of peaches works much better here, which doesn’t require a typical grafting knife.

For spring grafting, a grafting tool works much more precisely and provides good cambium contact, vs. a grafting knife, imo.

The Zenport style tool has lots of threads about it. I really like the design, although my particular tool was pretty defective. I’ve since fixed it and used it quite a lot with great success. I will never go back to a knife or special double blade pruners (both of which I’ve tried) to spring graft. Imo, using a knife, or trying to use double blade pruners to spring graft are like trying to “freehand” paint a long straight line on a canvas. It’s virtually impossible to do unless your are a grand master artist. Unless you are a master grafter (which is about as common as a master painter) you will be faking a straight line in your cuts, and using tape to cover over and squeeze out your small errors made in cutting.

Be aware the Zenport style grafting tool can have some serious manufacturer flaws, depending on the particular item you receive. I had to do some major work on mine, but since then I wouldn’t ever go back to using a free hand knife or clumsy pruners. The beauty of the tool is that it cuts the receiving rootstock with exactly the same accuracy as the scion portion, every time, with speed which can’t be matched freehand.

Here is a thread where I discuss repairing my Zenport tool I bought (Again one of many Zenport grafting tool threads.) I have since fallen in love with the tool for spring grafting. It provides such fast and accurate cuts on both the scion and rootstock, it’s a dream.

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I am doing with what I am doing all my grafting career, a little stone, solid black. It’s good enough for me.

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I send my knives to a professional knife sharpening service. I tried doing this myself on several knives but I just do not do it enough to get good at doing it. It is faster I know to do it yourself however, it is just something I do enough to be proficient at. I almost ruined a few knives over the past few years trying to sharpen them. I’ll send it away to the professional sharpener and know it it done right. They do a great job with all my kitchen knives as well so I have them all done at one time.
Kudos to those that do this themselves. A little whet stone action here and there is okay but if you really need to get a nice sharp edge and bevel on a knife I just leave it to someone that has the experience to know how to do it correctly. Just my 2 cents worth of info, if it’s worth even that.

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I use these:

Dead simple since I use a single edge straight grafting knife. Just need to maintain one angle. I keep them in my grafting basket.

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I now use my WorkSharp belt sharpener. I’m still only sharpening one side, but the give in the belt tends to make the edge convex. Those DMT are still in my grafting bag.

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It looks like you have (from top to bottom) a coarse/medium combination crystolon (silicone carbide) stone (120/320 grit usually), what I believe is an Arkansas stone (fine to extra fine/600-2000 grit, depending on if it’s “soft” or “hard” [different grades]), and a combination water stone (the red side is probably coarser). If your middle stone is indeed an Arkansas, it might be about as fine as the water stone, as the Japanese style stones use a different grit system. I think you could get away with just using the water stone, starting with the coarse and flipping to the fine.

It looks like you’re not using any lubricant, as I see lots of swarf (metal dust) built up. You absolutely MUST use a lubricant. The purpose of this is to lift the swarf and keep the abrasive from clogging. The crystolon should use a light synthetic oil like sharpening oil or 3-in-1. The waterstone must use water, and needs to be soaked for 10-30 min before use. An Arkansas stone can go either way (I like to use water with a drop of dish soap), but you should soak it in degreaser if it’s ever had oil on it if you want to use it with water. Another thing to note is that a Japanese stone cuts much faster, but you need to flatten it frequently for best performance.

Edit: looking at your pictures more closely, the middle stone may be a finer grit crystolon stone. It’s hard to tell, but it looks like there’s a clear seam with a different color material on the other side. You can have combination natural stones, but the seam doesn’t usually look quite that crisp.

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I like good tools, some will sit unused until the next fool arrives after I’m gone. I have two new of the red handled ones and two new “box cutters.” BUT, I’m getting one of those old table top machines if it can be found, and adding one of the hand held Scionon. Heck, spending money on someone I love.

Anyone using a steel to sharpen?

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Would Dawn work as a degreaser?

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I’m confused. Which sharpener do you use now? WorkSharp or DMT?

I sharpen my grafting knives with the WorkSharp. The DMT are still in my grafting bag. I imagine I may use the finest one on the flat to align the edge if I need to.

I don’t take the AC powered WorkSharp out into the orchard. I seldom do more than 10 or 15 grafts in a session these days though.

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A honing steel doesn’t really sharpen a knife, it aligns the teeth and to some extent abrades the thin layer the teeth rest on. Ceramic sharpeners IMO are a better choice though there are plenty of professionals who swear by a honing steel. Besides ceramic hones, there are diamond hones on the market now. They remove a thin layer of metal with use so can be used for actual blade sharpening.

I’ve sharpened my knives many times with my Lansky diamond sharpeners. Then I figured out how to adapt a belt sander with very fine grit belts for the purpose. It is faster, more accurate, and gives very precise edge control.

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It does a little bit, but a dedicated degreaser product is much more thorough. I like Citrasolv, but Simple Green is a popular choice as well.

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A smooth honing steel actually sharpens, via adhesion. It is however a small effect best noticed on an already razor sharp knife.

For most people honing just bends a bur back to roughly the middle and “fakes” sharpness for a very short time till the hone is needed again.

If never understood why hones are still around. When for a similar price you can often get a “splash and go” polishing whetstone. And that will outperform the hone by miles. And is virtually the same to use.

How fine a grit did you source? The lansky i think has 1000 “grit” diamond as it’s finest. Witch is still quite rough, especially since diamonds leave deep scratches and thus act like a courser “stone” than they are. If got a 1200 atoma plate that leaves a courser finish than a 1000 water stone. (combi stone naniwa)

my polishing stones are splash and go. And it takes 20 seconds after a day of grafting to make a few strokes on the stone with my knife. And it keeps it insanely sharp.

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I just read this. Although i agree that sharpening “culture” is often filled with lots of people shouting hard. Without having the results to back it up.

There is a flaw in your above reasoning. It’s not just the angle that determines sharpness. But in a large part also the finish of the cutting edge. The finer the finish (more polished) the sharper. You can get a 45 degree angle (inclusive) sharper than a 20 degree (inclusive) if the 45 is polished on a fine stone. And the 20 degree is only sharpened on a rough stone or plate.

There is also a huge debate about convex vs flat vs hollow. I’ve not seen noticeable differences though. (for primary edge)

There is even the practice of giving a knife a micro bevel. That’s sharpening the cutting edge of the knife at an higher angle, on a very fine stone to get it sharper.

Thus increasing the sharpening angle to increase the sharpness of the knife.

That’s possible because sharpness is not only determined by the angle. But the combination of angle and finish.

If you take it to the electron microscope level. An important part of sharpness and edge retention comes from the carbides. And the carbides are bigger than the rest of the metal. And thus if you where to sharpen those on to smal of an angle, the carbides would brake out. And leave you with a smaller angle but less sharp knife. This however for most practical applications does not happen.

What does happen a lot is edge rollover from use. (the cutting edge bending, especially at low angles)

Convex geometry actually resists that a little better.

I don’t think consistency of angle is that great of importance. Sure you don’t want huge inconsistency’s (going between 50 and 10 degree’s for example) but some inconsistency in angle leads to a convex cutting edge. And in my opinion is desirable. Especially when cutting wood.

as a last example, i once polished the spine of a knife (for looks) but had to round it off after repeatedly drawing blood from that 90+ degree polished angle i created at the spine of the knife.

i think freehand sharpening is a lot like grafting. You don’t have to be an absolute master to get good results. You don’t need absolute precision with the angle, just like you don’t need perfect carpentry or nanometer precision when aligning the cambium.

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I couldn’t agree more! There’s definitely some skill to it, but I think the biggest problem is not spending enough time on coarse stone (at least for initial sharpening) or skipping it all together. Heck, I sometimes get impatient and convince myself it’s time to move on when I should stick with the coarse stone. But rushing or skipping the coarse step just leads to frustration on the finer stones. You can get it sharp eventually (I’ve done it), but it takes a long time. And when it takes a long time, you’re more likely to rush and make mistakes.

This gets to the biggest reason I prefer sharpening with stones. When you’re doing it right, it’s a slow, meditative process. It’s very therapeutic for my ADHD brain to have something that can absorb the entirety of my focus.

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