Help with competition chopper style knife.

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Storm W

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Feb 19, 2019
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I'm making a large chopper that will be just a little larger than a true competition chopper. I'm using 1/4" A2. How thick is reasonable behind the edge? Also what would be a good hardness for this task?
 
I made one similar to what you are after (13" blade), out of 3/16" CPM 3V. I had Peters do the HT to 60 RHC. I followed Scott Gossman's suggestion to do a flat grind for 70%, then convex. It was fairly easy to do and ended up very sharp.
Could be overkill for baby carrots, but it worked well for 2x4s also.
OaxT56y.jpg
 
Richard338 said:
I made one similar to what you are after (13" blade), out of 3/16" CPM 3V. I had Peters do the HT to 60 RHC. I followed Scott Gossman's suggestion to do a flat grind for 70%, then convex. It was fairly easy to do and ended up very sharp.
Could be overkill for baby carrots, but it worked well for 2x4s also.
OaxT56y.jpg
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You going to a convexed near zero?
How is the 3V? I have a 3' piece of 1/4 still sitting for a couple of years
 
I love the 3V. Yes I convexed the last part right to a somewhat sharp zero. Then a few passes on a DMT got it very sharp. Chewing through a few 2x4s didn't dull it enough to bother sharpening again yet.
 
A number of years ago at the Guild Show in Orlando, I talked to a couple of the guys who had pioneered the "cleaver" style competition cutters made from CPM M4 and the forward mounted lanyard. They said that they would take them WAY down until they failed and then sharpen back until the it worked. IIRC, they said that they could get them down to around 15 thousandths behind the edge and still have them survive.
 
jdm61 said:
A number of years ago at the Guild Show in Orlando, I talked to a couple of the guys who had pioneered the "cleaver" style competition cutters made from CPM M4 and the forward mounted lanyard. They said that they would take them WAY down until they failed and then sharpen back until the it worked. IIRC, they said that they could get them down to around 15 thousandths behind the edge and still have them survive.
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I have a piece of .300 CPM M4 in reserve for the time when I know what I'm doing.
 
You want to use stock at least 1/4” thick. The pros use stuff .300” or even thicker. You want a lot of material to work with. I like a long full flat grind to near zero on mine.
 
JG Custom Metal Works said:
You want to use stock at least 1/4” thick. The pros use stuff .300” or even thicker. You want a lot of material to work with. I like a long full flat grind to near zero on mine.
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I bought some 3V as well .300 (I think) but the I found out that it isn't ideal for a real comp chopper so it will get made into a couple of crazy trail choppers after I get them down. I thought A2 was a nice compromise of price and performance
 
This thin works on Nathan's V4E, I was amazed how thin it was when I got it:eek::D

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~Chip
 
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Storm W said:
I bought some 3V as well .300 (I think) but the I found out that it isn't ideal for a real comp chopper so it will get made into a couple of crazy trail choppers after I get them down. I thought A2 was a nice compromise of price and performance
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Who said that 3v wasn’t ideal for a comp cutter? I imagine it wouldn’t work as well as M4 at holding a super thin, acute edge(which would be used for the precision cuts, like straws, paper, etc...). But it would work great for shopping.

For a “cheaper steel,” I know a lot of competitors are using 52100. It will take a super fine edge and is pretty tough. I got a comp chopper blade blank from Jose Diaz in .320” 52100. That could be an option for you. My plan was to make a few comp choppers to refine my design, and THEN make one out of M4 or Bohler Vanadis 4 Extra.
 
JG Custom Metal Works said:
Who said that 3v wasn’t ideal for a comp cutter? I imagine it wouldn’t work as well as M4 at holding a super thin, acute edge(which would be used for the precision cuts, like straws, paper, etc...). But it would work great for shopping.

For a “cheaper steel,” I know a lot of competitors are using 52100. It will take a super fine edge and is pretty tough. I got a comp chopper blade blank from Jose Diaz in .320” 52100. That could be an option for you. My plan was to make a few comp choppers to refine my design, and THEN make one out of M4 or Bohler Vanadis 4 Extra.
Click to expand...
Someone I'm not sure who(maybe Big Chris) said that with the thin edges 3V would sometimes stretch at the edge.

I have 6' of 0.25 A2 to play with. We will see where I go after that.
 
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