thinning questions (yet another thread)

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ian

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By "tip" i meant to say "edge." The thickness at the very edge is never going to be 0, but at the very least probably around 0.1mm

I think if your knife is .1mm at the actual edge, it will be really dull. Idk if the following is a razor or a knife, but 1 micrometer is a thousandth of a millimeter. The image is from Definitions of Sharp and Keen Anyway, I think @noj responded accurately.

Screen Shot 2022-12-05 at 12.14.12 PM.png
 

ian

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I own a good micrometer. I don’t think I am capable of measuring the thickness behind the edge (or 1 mm behind) with any accuracy; there’s simply too much guesswork for me. That said, if I sharpen around 15 degrees, it turns out if your bevel is 1 mm deep, it’s 0.5 mm wide (and just behind the edge). That seems a lot more than some have recommended, and a 1 mm bevel doesn’t seem excessive after a handful of sharpenings.

Yea, you should maybe view the recommendations as guidelines for what to shoot for when you have a really tiny bevel. And sometimes the recommendations people give are like razor measurements....

First, I understand different knife makers, or styles, will have different geometries, and there’s no one right answer. I own a Konosuke FM I like a lot. I have two others that don’t cut well. One is a Mizuno which came new very thick and convex, and I haven’t sharpened it much. The other is a 15 year old famous maker (not going to mention here) I got used, I haven’t sharpened, and also a convex grind. Measurements (in mm) at midpoint follow:

Konosuke FM 0.6 1.0
Mizuno 1.2 1.7
15 year old 1.0 1.4

I aim more for Kono FM thickness when I thin. Those other ones are chonky, although if you mostly cut soft stuff and find food release / indestructibility desirable, the thicker measurements could be good.

I don’t think I am capable of thinning the two thick ones above. A lot of work, and too valuable to me to get wrong. Any suggestions? I would want someone that won’t change the makers character and geometry too much (like someone that doesn’t do convex bevels).

Probably any of the reputable knife stores would do a good job. E.g. JKI, Strata Portland, Carbon Knife Co. I thought there was a new fancy knife store that opened up in Chicago, but can't remember the name. Anyway, I'm sure there's someone in Chicago that could do a good job. Maybe a local can weigh in. Or you can send them to @Runner_up or @Forty Ounce. :)

Jon’s (JKI) has a video on thinning wide bevel, but very little on thinning convex grinds. Any good threads or suggestions? I am having a hard time understanding how to comfortably and accurately maintaining a 5 degree angle, if that is an example of what’s required. There’s no obvious feedback like what one might get with a shinogi. I am looking for a lot of detail. Plus pitfalls I don't need to experience first hand;-)

Don't try to maintain a 5 degree angle. That's impossible. Do it all with finger pressure. If you keep your fingers pretty near the edge, metal will tend to be removed right under your fingers. If you move your fingers back a little, you'll remove metal there. Look frequently at the scratch pattern on the underside of the knife to verify that you're removing metal in the correct place. Don't worry about getting it perfect. 10 to 1, the convex grind wasn't perfect to begin with. Imo, it's much easier (although very time consuming) to create uniform convex geometry on stones than it is on a belt grinder anyway, which is what most of the makers are using, so as long as you pay attention you probably won't ruin anything. That said, I wouldn't practice on a $500+ knife at first.

I know there will be some. Low spots, high spots, etc. I am looking for the most common, and what to do with them. My guess is anything that gets to the cutting edge needs to be "fixed", less sure about the thinning area, and some are cosmetic (or will go away as the thinning progresses).

Low/high spots that don't hit the edge are only an aesthetic problem, in that they make it hard to polish the knife evenly on bench stones. They will minimally impact performance, and may actually improve food release a bit. If you actually have a hole in the edge, then yea, you should thin/reprofile until the profile is fixed.


----

In general, @HumbleHomeCook's relaxed approach is good advice. I definitely found target measurements reassuring when I was starting out, though. Aiming for < .7mmish and < 1.2mm at the 5mm and 10mm mark will probably give you something that'll separate food reasonably well, and you can decide how to tweak them from there. Nowadays I never measure though. Btw, the nail flex test is an easy way to test thinness near the edge. If you want a thin edge that'll scream through produce, just take the blade and press the side of the edge on one of your fingernails. If the metal slightly bends at the contact point (you'll see that light reflects differently there), it's thin enough.

Maybe one additional recommendation: when thinning make sure not to f up the profile. The biggest mistakes I've made thinning have always been while thinning down to a zero grind, and then continuing to thin further. For instance, when you're working on the edge and thinning at the same time, the steel can bend from the pressure near the edge, effectively making you thin near the edge at something like a 0 degree angle, so that you end up creating part of the edge that's like aluminum foil. If you don't notice that you're doing that, you can end up with a couple mm of foil, which then breaks off, ruining your profile. I think it's a better idea in general to separating thinning and messing with the profile as much as possible. Try not to be creating a burr when you're thinning.

How is the grind on Forgecrafts? Convex or wide / flat bevel?

edit: sorry, totally off-topic

I think they're pretty flat on the blade road, but someone who owns an unmodified one can correct me.
 
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noj

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I will catch up on all your generous comments in just a bit. I had an idea that seemed worth another bit of measuring and math. I got curious about how thin was in fact possible at 5 and 10 mm. Assuming you don't make it concave, the best case (for total thinness, not a good knife) is a V grind. I did the measurements somewhere in the upper middle, but well away from any heavy taper at the handle.
[SNIP] removed incorrect math, see below
 
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ian

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_________________spine, height, 5 mm**, at 10 mm**
Konosuke FM___ 2.2 mm, 47 mm, 0.5 mm, 1.0 mm
Mizuno__________ 2.9 mm, 40 mm, 0.7 mm, 1.4 mm
15 year old______ 3.1 mm, 47 mm, 0.6 mm, 1.3 mm

What are these? Like you're saying what the measurements would be with the given spine width/height if you had a V grind? Those measurements seem a little large, no? I'd expect a full V grind to give you measurements that were like half of those. At least, naively, if I imagine a knife as a triangular wedge with base of length 47 and height 2.2, and look at the triangle with the same apex angle where the base is 5, the height should scale by the same ratio as the base, so since 47/5 is a bit less than 10, you should get something a bit bigger than 2.2/10=.22 mm for the 5mm cross section. Maybe I'm confused about something. Anyway, remember to use a microbevel! Otherwise your V ground Kono FM will have an apex angle of 2.8 degrees. o_O
 
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noj

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What are these? Like you're saying what the measurements would be with the given spine width/height if you had a V grind? Those measurements seem a little large, no? I'd expect a full V grind to give you measurements that were like half of those. At least, naively, if I imagine a knife as a triangular wedge with base of length 47 and height 2.2, and look at the triangle with the same apex angle where the base is 5, the height should scale by the same ratio as the base, so since 47/5 is a bit less than 10, you should get something a bit bigger than 2.2/10=.22 mm for the 5mm cross section. Maybe I'm confused about something. Anyway, remember to use a microbevel! Otherwise your V ground Kono FM will have an apex angle of 2.8 degrees. o_O
Math done badly in my head, give me a sec;-)
 

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Math done badly in my head, give me a sec;-)
I wasn't proposing doing a V grind at all. I was just curious how far from that it was. Corrected math below. Clearly, a lot of metal can be removed before getting close to the V-grind. I like the Konosuke the way it is! Thanks for the catch.

_________________spine, height, 5 mm**, at 10 mm**
Konosuke FM___ 2.2 mm, 47 mm, 0.24 mm, 0.48 mm
Mizuno__________ 2.9 mm, 40 mm, 0.36 mm, 0.7 mm
15 year old______ 3.1 mm, 47 mm, 0.33 mm, 0.7 mm


47/1.1 = 5/(t5/2) -> t5 = 0.24 (or about .22 as you said), and t10 = 0.48
40/1.45 = 5/(t5/2) -> t5 = 0.36 and t10 = 0.7
47/1.55 = 5/(t5/2) -> t5 = 0.33 and t10 = 0.7

** with V grind <-------------!!
 
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Maybe one additional recommendation: when thinning make sure not to f up the profile. The biggest mistakes I've made thinning have always been while thinning down to a zero grind, and then continuing to thin further. For instance, when you're working on the edge and thinning at the same time, the steel can bend from the pressure near the edge, effectively making you thin near the edge at something like a 0 degree angle, so that you end up creating part of the edge that's like aluminum foil. If you don't notice that you're doing that, you can end up with a couple mm of foil, which then breaks off, ruining your profile. I think it's a better idea in general to separating thinning and messing with the profile as much as possible. Try not to be creating a burr when you're thinning.
This is important.

Creating a zero grind on a coarse stone will also risk mucking up the profile.

Maybe a good idea to stop just before this until you get a feel for it.
 

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I wasn't proposing doing a V grind at all. I was just curious how far from that it was. Corrected math below. Clearly, a lot of metal can be removed before getting close to the V-grind. I like the Konosuke the way it is! Thanks for the catch.

_________________spine, height, 5 mm**, at 10 mm**
Konosuke FM___ 2.2 mm, 47 mm, 0.24 mm, 0.48 mm
Mizuno__________ 2.9 mm, 40 mm, 0.36 mm, 0.7 mm
15 year old______ 3.1 mm, 47 mm, 0.33 mm, 0.7 mm


47/1.1 = 5/(t5/2) -> t5 = 0.24 (or about .22 as you said), and t10 = 0.48
40/1.45 = 5/(t5/2) -> t5 = 0.36 and t10 = 0.7
47/1.55 = 5/(t5/2) -> t5 = 0.33 and t10 = 0.7

** with V grind <-------------!!
Just based on personal experience, the thinnest I've seen an edge at 5mm that's still able to hold is around 0.45mm. And that's really nail flexing already. If you go below that, very good chance your edge turns to foil and fails. Depends on the type steel and it's heat treatment for how thin you can get it. But if you get to that point, you will know.
 

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Just based on personal experience, the thinnest I've seen an edge at 5mm that's still able to hold is around 0.45mm. And that's really nail flexing already. If you go below that, very good chance your edge turns to foil and fails. Depends on the type steel and it's heat treatment for how thin you can get it. But if you get to that point, you will know.
I have no intent to get that low, I was just curious what to compare various numbers against, though perhaps not that useful. Something in the ballpark of the Konosuke would suit my needs in terms of profile I like.
 

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If you are looking for a practice knife, I really like Forgecraft for this.


For measuring 1mm behind the edge, I put a mark on my calipers at 1mm. Line up the edge with the mark and consistent 1mm measurement all along the edge.

You’ll usually get the biggest performance benefit with thinning in the area just behind the edge. I usually take it down to 0.2-0.3 at a minimum.
Looks like the same maker is shown in the example above by @M1k3. Thanks, I'll have a look.
 

noj

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I think if your knife is .1mm at the actual edge, it will be really dull. Idk if the following is a razor or a knife, but 1 micrometer is a thousandth of a millimeter. The image is from Definitions of Sharp and Keen Anyway, I think @noj responded accurately.
This is what I was trying to model with my original calculation (zero edge width). Keep in mind, what I was trying to estimate was the width behind the edge by inspection (vs caliper). Re-calculating with a "fat" edge was actually interesting, since the answer (for behind the edge width) is about the same, just a little larger. Unless I discover otherwise, my best estimate is width behind the edge is about 1/2 the width of the bevel. That assumes about a 15 degree, and reasonably flat final bevel. No warrantee for wobbly wrists.
 

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Yea, you should maybe view the recommendations as guidelines for what to shoot for when you have a really tiny bevel. And sometimes the recommendations people give are like razor measurements....



I aim more for Kono FM thickness when I thin. Those other ones are chonky, although if you mostly cut soft stuff and find food release / indestructibility desirable, the thicker measurements could be good.



Probably any of the reputable knife stores would do a good job. E.g. JKI, Strata Portland, Carbon Knife Co. I thought there was a new fancy knife store that opened up in Chicago, but can't remember the name. Anyway, I'm sure there's someone in Chicago that could do a good job. Maybe a local can weigh in. Or you can send them to @Runner_up or @Forty Ounce. :)



Don't try to maintain a 5 degree angle. That's impossible. Do it all with finger pressure. If you keep your fingers pretty near the edge, metal will tend to be removed right under your fingers. If you move your fingers back a little, you'll remove metal there. Look frequently at the scratch pattern on the underside of the knife to verify that you're removing metal in the correct place. Don't worry about getting it perfect. 10 to 1, the convex grind wasn't perfect to begin with. Imo, it's much easier (although very time consuming) to create uniform convex geometry on stones than it is on a belt grinder anyway, which is what most of the makers are using, so as long as you pay attention you probably won't ruin anything. That said, I wouldn't practice on a $500+ knife at first.



Low/high spots that don't hit the edge are only an aesthetic problem, in that they make it hard to polish the knife evenly on bench stones. They will minimally impact performance, and may actually improve food release a bit. If you actually have a hole in the edge, then yea, you should thin/reprofile until the profile is fixed.


----

In general, @HumbleHomeCook's relaxed approach is good advice. I definitely found target measurements reassuring when I was starting out, though. Aiming for < .7mmish and < 1.2mm at the 5mm and 10mm mark will probably give you something that'll separate food reasonably well, and you can decide how to tweak them from there. Nowadays I never measure though. Btw, the nail flex test is an easy way to test thinness near the edge. If you want a thin edge that'll scream through produce, just take the blade and press the side of the edge on one of your fingernails. If the metal slightly bends at the contact point (you'll see that light reflects differently there), it's thin enough.

Maybe one additional recommendation: when thinning make sure not to f up the profile. The biggest mistakes I've made thinning have always been while thinning down to a zero grind, and then continuing to thin further. For instance, when you're working on the edge and thinning at the same time, the steel can bend from the pressure near the edge, effectively making you thin near the edge at something like a 0 degree angle, so that you end up creating part of the edge that's like aluminum foil. If you don't notice that you're doing that, you can end up with a couple mm of foil, which then breaks off, ruining your profile. I think it's a better idea in general to separating thinning and messing with the profile as much as possible. Try not to be creating a burr when you're thinning.



I think they're pretty flat on the blade road, but someone who owns an unmodified one can correct me.
Thanks, lots of good info. The knife stores you mentioned are not accepting new work. Strata says they take mail-in, but when I called last, they said they didn't, and in any case it says they aren't doing complex stuff. Following up on other leads, but no luck yet.

I am glad it's a finger pressure method. I can't maintain a 5 degree angle either.

I did make yet another attempt on my full stainless beater. I used a 120 grit Shapton Pro and magic marker, and worked one side only. Well, the knife has about 5 low spots going to the edge, or pretty close. After an hour's work, it's still too thick, from the midpoint to heel, for the stone to get near the edge (maybe 1+ mm sharpie worth). I am guessing I need to change the geometry so as to be able to hit metal, based on finger pressure, from edge to 5+ mm above.

Perhaps a property of cheap stainless, but it started to polish vs abrade. I kept refreshing my Shapton on a silicon carbide plate (it's an 15" x 15" kiln shelf). The stone felt deglazed to my fingertips. Maybe the stainless is hardening due to deformation? I have to imagine a lot of hours/days of work. I mean practice;-) My only other low grit stones are a fast-dishing JKI 220, and a Shapton Pro 320.

Maybe I need a full carbon, or carbon clad? Forgecraft on ebay can get expensive for a practice knife. The ones in better condition were $100+. There are cheap Old Hickory ones.

I'll keep your other recommendations in mind as I proceed.
 
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Thanks, lots of good info. The knife stores you mentioned are not accepting new work. Strata says they take mail-in, but when I called last, they said they didn't, and in any case it says they aren't doing complex stuff. Following up on other leads, but no luck yet.

I am glad it's a finger pressure method. I can't maintain a 5 degree angle either.

I did make yet another attempt on my full stainless beater. I used a 120 grit Shapton Pro and magic marker, and worked one side only. Well, the knife has about 5 low spots going to the edge, or pretty close. After an hour's work, it's still too thick, from the midpoint to heel, for the stone to get near the edge (maybe 1+ mm sharpie worth). I am guessing I need to change the geometry so as to be able to hit metal, based on finger pressure, from edge to 5+ mm above.

Perhaps a property of cheap stainless, but it started to polish vs abrade. I kept refreshing my Shapton on a silicon carbide plate (it's an 15" x 15" kiln shelf). The stone felt deglazed to my fingertips. Maybe the stainless is hardening due to deformation? I have to imagine a lot of hours/days of work. I mean practice;-) My only other low grit stones are a fast-dishing JKI 220, and a Shapton Pro 320.

Maybe I need a full carbon, or carbon clad? Forgecraft on ebay can get expensive for a practice knife. The ones in better condition were $100+. There are cheap Old Hickory ones.

I'll keep your other recommendations in mind as I proceed.
You could try Ryan Swanson at District Cutlery. I think he is taking thinning work.

That Forgecraft I linked I bet won't go for much more than the opening bid price. It looks in fine condition. Close to original profile is what you are looking for in vintage knives. A little rust is not a problem, cleans up easy. They are also just great knives. I used mine last night to make dinner, inspired by this thread. Reminded me how much I like it.

That said, Old Hickory or Dexter (especially the 49A10H) will be fine for practice too. Vintage knives are exactly how I learned to thin and polish knives before taking the bevels of fancy Japanese knives to stones.
 

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A couple more questions before I get my hands on the Forgecraft.

Do you generally do thinning all along the edge length?

Does it matter where you start (tip/heel/tbd)?

This may be harder to answer, but how should I be gauging the amount of metal removal along the edge (from tip to heel). I can imagine starting by rounding the shoulders to get a uniform and thin (or near zero) edge grind. I can imagine addressing what is going on above the edge (like 5 mm 10 mm) after, if needed.

If I need to do more than round shoulders, any guidance as to how to proceed? I understand the endgame is some combination of getting close to whatever measurements are desired, and ultimately does it work in the kitchen. I just don't yet have a clear method in my head about what to focus on.

I have seen blades that have an almost constant thickness 5 mm behind the edge. My Konosuke leans in this direction. Others are distinctly thinner towards the tip. I am guessing, just stick to the existing profile, at least until I get better at this.

Any additional details or corrections welcome.
 
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A couple more questions before I get my hands on the Forgecraft.

Do you generally do thinning all along the edge length?

Does it matter where you start (tip/heel/tbd)?

This may be harder to answer, but how should I be gauging the amount of metal removal along the edge (from tip to heel). I can imagine starting by rounding the shoulders to get a uniform and thin (or near zero) edge grind. I can imagine addressing what is going on above the edge (like 5 mm 10 mm) after, if needed.

If I need to do more than round shoulders, any guidance as to how to proceed? I understand the endgame is some combination of getting close to whatever measurements are desired, and ultimately does it work in the kitchen. I just don't yet have a clear method in my head about what to focus on.

I have seen blades that have an almost constant thickness 5 mm behind the edge. My Konosuke leans in this direction. Others are distinctly thinner towards the tip. I am guessing, just stick to the existing profile, at least until I get better at this.

Any additional details or corrections welcome.
I'm not the most experienced sharpener here, but a couple of things I learned in the process...

The most important IMO is asking where exactly can you thin to improve the knife's performance. Try it on some carrots and see how it performs. Do they crack right at the beginning of the cut, or near the end (when the edge is closer to the board)? The former might indicate it's thick BTE; the later could be an issue with the shoulders. Does it wedge / crack along the whole blade? It's usually better near the tip (so you thin less there). Like @stringer said - go slow, thin a bit here, test it on food, thin a bit there, test again...

I would be careful with the tip (the last 5cm or so). In my experience it needs much less thinning (about 1/10 of the effort or so) compared to the rest of the blade. That varies a lot from knife to knife of course. But I have overthinned more than one tip and ended up losing a few mm (in length and height). You usually only notice when it's too late.

Usually I start by smoothing the shoulders and thinning BTE. Lay the bevels flat on the stone and apply pressure near the edge. You'll end up thinning the whole bevel but focusing on the BTE area. Then tilt the knife a bit (so the spine is a bit closer to the stone), so you are hitting exactly at the shoulders, and then work there a bit. Thinning BTE - easing shoulders - moving shoulders up...
 
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A couple more questions before I get my hands on the Forgecraft.

Do you generally do thinning all along the edge length?

Does it matter where you start (tip/heel/tbd)?

This may be harder to answer, but how should I be gauging the amount of metal removal along the edge (from tip to heel). I can imagine starting by rounding the shoulders to get a uniform and thin (or near zero) edge grind. I can imagine addressing what is going on above the edge (like 5 mm 10 mm) after, if needed.

If I need to do more than round shoulders, any guidance as to how to proceed? I understand the endgame is some combination of getting close to whatever measurements are desired, and ultimately does it work in the kitchen. I just don't yet have a clear method in my head about what to focus on.

I have seen blades that have an almost constant thickness 5 mm behind the edge. My Konosuke leans in this direction. Others are distinctly thinner towards the tip. I am guessing, just stick to the existing profile, at least until I get better at this.

Any additional details or corrections welcome.
Speaking to Forgecraft specificially (I've done two of them, so not an expert, but I've been there), they are made from flat stock, no distal taper, so the blade road has a pretty even thickness from heel to tip.

It's probably going to need refinishing on the whole bevel. You can work it the way you would a wide bevel knife. Grind along the top of the bevel at the shinogi. Work up there will mostly be to even things out and take off any rust/piting. Then work with pressure close to the edge. You can introduce some convexivity here, or keep the bevels flat, up to you. You can lift the spine a degree or two to get more convexivity, or not. Work each side evenly.

Not sure what stones you'll be using, but in general this process is slow. Metal doesn't just fly off when thinning, it takes a long time.

When you are happy with the progress and want to make it look nice you can move up in grit on stones to remove the deeper scratches then move to wet/dry sandpaper to shine the bevels up. These are purported to be made of 1095 steel, one reason why they are so well regarded. It would be possible to get them looking good with stones alone, but I certainly didn't have the patience for that. Sandpaper makes it much easier.

For the faces, they can be cleaned up on (flat) stones, then sandpaper. I like to put the paper on a flat surface. It helps to keep things crisp. Some sanding of the handle may be required also. If so then again with the paper on a flat surface for sanding the sides of the scales as it keeps things even. Otherwise its pretty easy to grind more wood than the pins.
 
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It seemed line Ian was suggesting finger pressure alone to adjust the location of metal removal, vs lifting spine, if I read that right. Or at least, one can't accurately hold a low angle, but maybe a little inaccuracy helps with the convexity. I have tried this a little (on a different knife), but don't have any conclusions, other than it doesn't seem like I have much control lifting the spine by guesswork.

For stones, I have a shapton pro 120, this one glazes over fast. I have a JKI 220 soft soaker, dishes fast. Finally, a shapton pro 320.

I have a Naniwa Chosera 400, but that's probably way too fine for gross metal removal.
 
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It seemed line Ian was suggesting finger pressure alone to adjust the location of metal removal, vs lifting spine, if I read that right. Or at least, one can't accurately hold a low angle, but maybe a little inaccuracy helps with the convexity. I have tried this a little (on a different knife), but don't have any conclusions, other than it doesn't seem like I have much control lifting the spine by guesswork.

For stones, I have a shapton pro 120, this one glazes over fast. I have a JKI 220 soft soaker, dishes fast. Finally, a shapton pro 320.

I have a Naniwa Chosera 400, but that's probably way too fine for gross metal removal.
Certainly the SP120 will be fastest, but the scratches are deep. I would probably start with the JKI 220 and see how it goes. Try to use all the stone to avoid excessive dishing. I try to make a conscious effort to NOT use the middle of the stone. Especially when thinning.

Yes, where you are putting pressure is where the metal will come off. My suggestion of lifting the spine, it's almost not lifting at all, more using the guiding hand to exert pressure toward the bevel and away from the spine.

Really, I think you just have to put steel to stone and figure it out through trial and error. Like sharpening its hard to put it all into words and there are a million different ways of attacking it. Experiment and find what works best for you and the knife you are working on. In the end the first go at it might not be perfect, but you'll learn a lot, and you aren't going to ruin the knife.

This whole discussion is making me want to thin my Forgie a little more. :)
 
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Last I looked, there were a dizzying number of microscopes on sale. Which one are you using, or perhaps more key is what are key features for this application? I imagine focus range, magnification (not including pure digital, which I can do easily later on computer), and pixel resolution.
Money no object: something from Dino-Lite. Probably want to talk to an informed dealer sales rep because the range is truly dizzying.

Slumming it: any of these China-made 720p-claiming-to-be-4K will disappoint you in expected, familiar ways. This is what I have.
9A5D68C4-3AA2-4C56-9B10-870E9CB24A79.jpeg


This old video shows the difference between a cheap scope and a Dino-Lite. Skip forward to about the 7 or 8 minute mark.



And here’s a scope thread from a different forum. Microscope Test aka the Scope Showdown! – Wicked Edge Precision Knife Sharpener
 
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noj

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Money no object: something from Dino-Lite. Probably want to talk to an informed dealer sales rep because the range is truly dizzying.

Slumming it: any of these China-made 720p-claiming-to-be-4K will disappoint you in expected, familiar ways. This is what I have.


This old video shows the difference between a cheap scope and a Dino-Lite. Skip forward to about the 7 or 8 minute mark.



And here’s a scope thread from a different forum. Microscope Test aka the Scope Showdown! – Wicked Edge Precision Knife Sharpener

Thanks!
 

noj

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Well, a different (from the auction one) went for sale without a high price tag, so I snagged it.

I spent an hour in the on my 120 just cleaning up the bevel to see what I am dealing with. My 120 is slow, and seems to almost polish. I did a quick magic marker for the sake of photo. There are some low spots, but doesn't look too bad. The high spot right at the heel is annoying, but will go away eventually I hope. The other side has somewhat different issues, and seems similar in scope.

Pictures of one side below.

20221208_141721[1].jpg
20221208_142800[1].jpg
 
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Well, a different (from the auction one) went for sale without a high price tag, so I snagged it.

I spent an hour in the on my 120 just cleaning up the bevel to see what I am dealing with. My 120 is slow, and seems to almost polish. I did a quick magic marker for the sake of photo. There are some low spots, but doesn't look too bad. The high spot right at the heel is annoying, but will go away eventually I hope. The other side has somewhat different issues, and seems similar in scope.

Pictures of one side below.

View attachment 212935 View attachment 212936
Nice. If it interests you, here is a good thread on some of the history on Forgecraft knives. The stamps changed a bit over the years they were made, you might be able to get a better idea of date on it.

 
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Delat

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Well, a different (from the auction one) went for sale without a high price tag, so I snagged it.

I spent an hour in the on my 120 just cleaning up the bevel to see what I am dealing with. My 120 is slow, and seems to almost polish.

I’m definitely no expert, but IME when a low grit stone starts to polish it means it’s loaded up and needs cleaning. Sadly very frequent with low grit stones and why you see so many threads about low grit stones that don’t clog which usually end up with a recommendation for sandpaper.

My first go at thinning got tired of cleaning my loaded SG220, switched to an India and loaded that up, then said screw it and bought sandpaper. Next time I try thinning I need to pick up a kasfly.
 
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