Hello, I got an order for a knife that is a tanto point with a chisel grind I've looking at knives made by Daniel fairly it looks like he has a primary and secondary bevel on his chisel grinds. So I was wondering if a v grind knife was say 10 degrees per side for the primary bevel and 17-30 per side for the secondary bevel. So if you had a chisel grind could you do the primary at 20 and the secondary at like 35? This is for a 9 inch long knife made of .250 A2 so it will probably see some hard use. Any advice?
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Chisel grind blade geometry
- Thread starter Wheelz87
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I generally like to do a thin grind (.005"-.010" at the edge) and then a microbevel at around roughly 30 degrees. You can add the microbevel to the main bevel for an aggressive cutter or to the reverse for more versatility.
I really grind by looks and feel and do not measure anything... I just started measuring stuff to help people out.
I really grind by looks and feel and do not measure anything... I just started measuring stuff to help people out.
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Hey thanks! I'm always happy to help too so just let me know if you ever have any questions.
Add the microbevel to the main - I just mean apply it to the same side as the bevel.
Feel free to post a pic of the knife you are talking about and i'll do my best to explain how I ground it.
Oh ok you're saying you can add a micro bevel to the flat side of the knife and it will be more versatile. Add it to the bevel side and it will cut more aggressively. I'm glad I asked you guys cause I would have left the edge way too thick. Learn something every day.
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People overthink the angles and such on bevels, and especially on tanto.
Most primary bevels are around 10° included angle. What it is exactly isn't important. The bevel is a flat surface from the edge to the top of the bevel. That can be any point from halfway up the blade to a full Flat Grind to the spine. The bevel angle is going to be a product of the grind height and the blade thickness....nothing will alter that. You change the stock thickness to get a more or less acute angle.
The secondary bevel is the one you can control. It is usually very small, only going up the blade the amount necessary to form the angle. That is usually just a few hundredths of an inch. On a chopper edge that is .010" thick, a 20° secondary bevel will only go .030" up the primary. On a thin slicer with a .005" edge thickness, a 15° secondary rises .020".
Some examples with numbers:
A 1" blade with a FFG that is 1/4" thick will have a 14° angle (7° per side)
A 1" blade that is 1/8" thick will have a 7° angle ( 3.5° per side)
A big Bowie that is 2" high and 1/4" thick has a bevel angle of 7° ( 3.5° per side)
To make a chisel grind tanto, the process is simple and does not require math. This is why it is so ancient. Here is a basic tutorial:
The American Tanto is angular and straight in shape (sugata). The American Tanto tip is usually a straight angle, often at 45°, while the classic Japanese tanto is slightly curved and has a curved tip (kissaki). The kissaki can be blunt or very long and tapered as the maker wishes. Many Japanese tanto resemble a fillet knife more than a weapon.
Steps in making a tanto:
1) Flatten the back of the steel bar (ura - back or "hidden" side). It is often a very slight concave grind (hollow ground on a 60" wheel for best cutting results), but flat is good enough. Once the back is flat/concave, you are done with it. No secondary bevels should be ever be added here. The ura side should be at the final pre-polish grit now. Putting duct tape on the back while working the front can prevent damage.
2) Flatten the front side of the blade steel (omote - front or "show" side). If the blade will have distal taper ( recommended), do that now. Once the omote is flat and tapered. the upper balde surface is established and won't be altered.
3) Form the blade shape. Grind the profile to the desired shape. This should be fairly close to the final shape, as any changes later will affect the bevels and edge thickness. The blade shape is called the sugata. On a tanto, the tip ( kissaki) is often left square, as the final shape is best formed last.
4) Form the primary bevel. Decide how high it will go up the blade face and make the grind parallel to the edge. When done it is a flat plane from the edge to the ridge line ( shinogi). The bevel from the edge to the ridge is the ha-ji, and the flat from the ridge to the spine ( mune) is the shinogi-ji. The grind type when the bevel goes part way up the blade is called shinogi-tsukuri. If the bevel goes all the way to the spine ( as is common in Japanese tanto) it is called hira-tsukuri.
The shinogi-ji and ha-ji can be taken to the final grits before hand polish now.
5) Form the tip (kissaki) shape. Tape off the rest of the blade to keep scratches down. Grind the shape of the tip in slowly, looking at it in profile until the right shape is made. It can be a straight line or be curveed ( fukura).
6) Form the tip bevel. Carefully walk the grind back from the tip edge forming the line that separates the blade edge from the tip edge. This line is called the yokote. The line from the shinogi to the spine ( mune) is called the ko-shinogi ( little ridge). The point where the yokote, shinogi, and ko-shinogi meet is called the mitsukado ( three corners).
When the kissaki is formed and at the finest grit, it should have crisp lines separating it from the rest of the blade features. The yokote should be as vertical as possible. All shinogi should be parallel to their corresponding edges.
7) Hand finish and polish the blade. Power buffing will ruin the crisp flat surfaces and shinogi lines, so polishing by hand with hard backed leather and/or hard felt blocks is the best way to get the ha-ji shiny. The shinogi-ji is best left at a sanded satin finish.
8) Last step is to add the tiny secondary bevel to the omote side edge. This should be at the desired use angle. Normally between 15° and 20°.
Most primary bevels are around 10° included angle. What it is exactly isn't important. The bevel is a flat surface from the edge to the top of the bevel. That can be any point from halfway up the blade to a full Flat Grind to the spine. The bevel angle is going to be a product of the grind height and the blade thickness....nothing will alter that. You change the stock thickness to get a more or less acute angle.
The secondary bevel is the one you can control. It is usually very small, only going up the blade the amount necessary to form the angle. That is usually just a few hundredths of an inch. On a chopper edge that is .010" thick, a 20° secondary bevel will only go .030" up the primary. On a thin slicer with a .005" edge thickness, a 15° secondary rises .020".
Some examples with numbers:
A 1" blade with a FFG that is 1/4" thick will have a 14° angle (7° per side)
A 1" blade that is 1/8" thick will have a 7° angle ( 3.5° per side)
A big Bowie that is 2" high and 1/4" thick has a bevel angle of 7° ( 3.5° per side)
To make a chisel grind tanto, the process is simple and does not require math. This is why it is so ancient. Here is a basic tutorial:
The American Tanto is angular and straight in shape (sugata). The American Tanto tip is usually a straight angle, often at 45°, while the classic Japanese tanto is slightly curved and has a curved tip (kissaki). The kissaki can be blunt or very long and tapered as the maker wishes. Many Japanese tanto resemble a fillet knife more than a weapon.
Steps in making a tanto:
1) Flatten the back of the steel bar (ura - back or "hidden" side). It is often a very slight concave grind (hollow ground on a 60" wheel for best cutting results), but flat is good enough. Once the back is flat/concave, you are done with it. No secondary bevels should be ever be added here. The ura side should be at the final pre-polish grit now. Putting duct tape on the back while working the front can prevent damage.
2) Flatten the front side of the blade steel (omote - front or "show" side). If the blade will have distal taper ( recommended), do that now. Once the omote is flat and tapered. the upper balde surface is established and won't be altered.
3) Form the blade shape. Grind the profile to the desired shape. This should be fairly close to the final shape, as any changes later will affect the bevels and edge thickness. The blade shape is called the sugata. On a tanto, the tip ( kissaki) is often left square, as the final shape is best formed last.
4) Form the primary bevel. Decide how high it will go up the blade face and make the grind parallel to the edge. When done it is a flat plane from the edge to the ridge line ( shinogi). The bevel from the edge to the ridge is the ha-ji, and the flat from the ridge to the spine ( mune) is the shinogi-ji. The grind type when the bevel goes part way up the blade is called shinogi-tsukuri. If the bevel goes all the way to the spine ( as is common in Japanese tanto) it is called hira-tsukuri.
The shinogi-ji and ha-ji can be taken to the final grits before hand polish now.
5) Form the tip (kissaki) shape. Tape off the rest of the blade to keep scratches down. Grind the shape of the tip in slowly, looking at it in profile until the right shape is made. It can be a straight line or be curveed ( fukura).
6) Form the tip bevel. Carefully walk the grind back from the tip edge forming the line that separates the blade edge from the tip edge. This line is called the yokote. The line from the shinogi to the spine ( mune) is called the ko-shinogi ( little ridge). The point where the yokote, shinogi, and ko-shinogi meet is called the mitsukado ( three corners).
When the kissaki is formed and at the finest grit, it should have crisp lines separating it from the rest of the blade features. The yokote should be as vertical as possible. All shinogi should be parallel to their corresponding edges.
7) Hand finish and polish the blade. Power buffing will ruin the crisp flat surfaces and shinogi lines, so polishing by hand with hard backed leather and/or hard felt blocks is the best way to get the ha-ji shiny. The shinogi-ji is best left at a sanded satin finish.
8) Last step is to add the tiny secondary bevel to the omote side edge. This should be at the desired use angle. Normally between 15° and 20°.
Last edited:
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You've got it!
Final use has a lot to do with edge geometry. Test like crazy until you know what the steel will do and then keep on testing. I keep going thinner and thinner... RC also has to do with edge stability and finer edges will often do better at a higher RC which to me was counter intuitive. Use your knives daily for everything and you will find yourself tuning the geometry to suit your use.
I'm about to do a video on bevel grinding next... hopefully I can show some of what i am looking for when I grind.
On thing I have noticed is that getting a low enough bevel to cut nicely can often work out better on a chisel ground knife... making them has taught me a lot about how thin and low you can go. (and it was thinner and sharper than I thought!)