Camp chopper knife edge question ( edge convex/appleseed)

[PaulDiStefano]

Hey everyone, I had a question about convexing an edge on flat ground choppers. I have been flat grinding all my big choppers and then at about 1/8inch up the blade I'll convex the edge making a small appleseed style edge and then sharpen from there. When testing on 2x4 chops and other wood chopping I get no chipping or edge deformation. But when I see pictures of mastersmith chopping knives and some bowies I will see flat grinds but about 1/4 inch up the blade of an appleseed edge.
What are your guys' thoughts. Is it better to be safer then sorry with convexing the edge to about 1/4" instead of a small convex at the very edge before sharpening. I'm torn because I see 10" blade production knives with flat grind and 0 appleseed/slight convex edge, but then I see a forged blade with a huge appleseed edge.
I guess I just need advice on user experiences and what you guys think is the best type of flat then convexed edge thickness/height.
Thanks bros,
Paul

 

[Stacy E. Apelt - Bladesmith]

This isn't meant to be a smart aleck answer, but the only way you will know is to sharpen it one way and test, then sharpen the other and test.

In the real word, there isn't much difference between a long convex and a FFG ending in a shorter convex. The major reason for one or the other is the actual use you will put the blade to. If I was making the knife to chop 2X4s I would go for more robust ... if it was going to chop kindling, ropes and vines, and then also cut some food up for dinner, I would use a finer edge with a smaller convex.

 

[PaulDiStefano]

This isn't meant to be a smart aleck answer, but the only way you will know is to sharpen it one way and test, then sharpen the other and test.

In the real word, there isn't much difference between a long convex and a FFG ending in a shorter convex. The major reason for one or the other is the actual use you will put the blade to. If I was making the knife to chop 2X4s I would go for more robust ... if it was going to chop kindling, ropes and vines, and then also cut some food up for dinner, I would use a finer edge with a smaller convex.

Thanks Stacy, Your right I will have to do some tests comparing the two soon. I was just curious to see what people's opinions on this were. I have been taking the edge to about a dime thickness for choppers and then convexing it to sharp. Do you think maybe like a nickel thickness is what people like Adam derosier or Burt foster use on their massive choppers before convexing it down to sharp. Idk the exact thickness because I don't have a digital caliper.
Thanks again
Paul

 

[Stacy E. Apelt - Bladesmith]

I can't say what Burt and the others you mentioned are taking their knives to before convexing, but the folks I know go much thinner. A dime is .05" thick ( 1.35mm) and a nickle is .08" ( 2mm). I go down to .02" on heavy use knives before convexing. If those numbers are right, seems that the blades would behave like hatchets.

The thickness you mention is often given for pre-HT thickness of the edge, but in actuality, half the thickness of a dime (025" - .03") is more than enough for a carbon blade at HT. After cleanup post-HT, that will be .02". On hunters, I take them down to .01" or less before convexing. The convex edge on a slicer starts at .005".

 

[PaulDiStefano]

I can't say what Burt and the others you mentioned are taking their knives to before convexing, but the folks I know go much thinner. A dime is .05" thick ( 1.35mm) and a nickle is .08" ( 2mm). I go down to .02" on heavy use knives before convexing. If those numbers are right, seems that the blades would behave like hatchets.

The thickness you mention is often given for pre-HT thickness of the edge, but in actuality, half the thickness of a dime (025" - .03") is more than enough for a carbon blade at HT. After cleanup post-HT, that will be .02". On hunters, I take them down to .01" or less before convexing. The convex edge on a slicer starts at .005".

Thanks for all that info!! That helps a lot.

Paul