Bladesport chopper

[james terrio]

Vanadis 4E has the advantage of the finer powder granules.
CPM 4V has the advantage of being available to buy.

That looks like one HECK of an advantage.

No kidding There are plenty of alloys that look great on paper, but that doesn't do much good if you can't get them, or can only get them in inappropriate sizes.

 

[mr_anderson]

Similar makeup. I know they are different brands.

Do you mean they are similar or the same steel?

It is my understanding that CPM-4V is a steel from Crucible, and Vanadis 4 Extra comes from Böhler-Uddeholm.

 

[mr_anderson]

I hope Zero Tolerance can keep the stuff in stock for their new knives. Back to topic, what about something like Vanadis 23? I've only seen one knife made with this, not a chopper, but it could take some serious abuse.

 

[JG Custom Metal Works]

I just wanted to post here and let you guys know I really appreciate all the time you've taken to share your wisdom with me. I'm gonna get a slab of 52100 on the way as soon as I get the chance. Unfortunately I'm going through some family crisis at the moment and everything else is having to take a back seat. I just didn't want you guys to think I don't appreciate all the help if I'm not able to post frequently. Im digging through the thread doing research every chance I get. Thanks again everyone.

 

[marthinus]

I have found this thread interesting to read and just wanted to ad something I read from Ed Schempp that caused me to rethink the application of CPM-M4 as a competition cutter, for me at least, and thought others might find it interesting as well.

There is a tendency for CPM M4 to work harden in the very thin geometry of a knife blade. Blade sports competitors push the limits and some of these very thin blades work harden and fracture or crack after a year or two on competition, and are replaced. Personally I used 52100 clad with 15N 20 for several years, and the knife is still undamaged. For large blades I prefer high Carbon to stainless or high speed steel. I like to think that my blades will outlive me.
There are many special purpose steels that will give exceptional life with light cutting tasks. Many of these steels will be used and do well in folding knives, it depends on what you like in your knife...Tke Care...Ed

 

[JG Custom Metal Works]

So I'm getting ready to order some 52100 steel for my chopper. I notice that a lot of the handles have a good amount of angle built into them. I imagine that in order to achieve this I would need a 3in wide piece. Would it need to be larger?

I'd like to make something similar to Dan's competition cutter or Jose Diazs' Cane Toad Chopper. I will probably go with 5/16in thick stock too. I've been looking for 52100 steel in these dimensions(3in wide, 5/16in thick, and 15in long), but haven't had any luck finding any. I've looked at NJ Steel Baron, USA Knifemaker, and Jantz and they don't have any. Does anyone know where I could find a reasonably priced slab like this?

 

[dphillips]

I couldn't find any either, which is why im gonna test A2.

 

[worldwood]

I called Aldo at NJ steel baron several months back and was able to get a piece of 52100 in .265" thickness and 3"X24"..... I was unable to find a piece .32-.35"... Thats what i really wanted....

Maybe give him a call directly. He sometimes has stock on hand thats not listed on the site and you may be able to get what you want.

I still have that slab just laying here.. I dont have the tools to make knives but i have an issue with "impulse" buying things sometimes LOL

 

[Dan Keffeler]

Jose Diazs and I get our 52100 from Kelly Couples. I have lost his contact info but I will ask Jose for it.
Dan

 

[JG Custom Metal Works]

Jose Diazs and I get our 52100 from Kelly Couples. I have lost his contact info but I will ask Jose for it.
Dan

I just gave Kelly a call(509-949-5231) and he doesn't have anything that thick. Just 5/32 and 1/8. He said Ray Kirk would probably have some round stock but I only do stock removal and don't have the means/know how to beat it into the thickness I'd need. Hmmmm... the hunt continues. I'll let you all know if I find some.

Hey Dan, what width do you use for your comp cutter? Thanks again for the help.

ETA: Spoke with Aldo, Ray Kirk, Sullivan Steel, and Kelly Couples and none of them have 52100 at 5/16in thick. Dang it. Might have to look at a different steel or possibly using 1/4in 52100...

 

[Willie71]

So I'm getting ready to order some 52100 steel for my chopper. I notice that a lot of the handles have a good amount of angle built into them. I imagine that in order to achieve this I would need a 3in wide piece. Would it need to be larger?

I'd like to make something similar to Dan's competition cutter or Jose Diazs' Cane Toad Chopper. I will probably go with 5/16in thick stock too. I've been looking for 52100 steel in these dimensions(3in wide, 5/16in thick, and 15in long), but haven't had any luck finding any. I've looked at NJ Steel Baron, USA Knifemaker, and Jantz and they don't have any. Does anyone know where I could find a reasonably priced slab like this?

If you have a torch, or a forge, you could just heat the tang and bend it to where it needs to be. Even a small plumbers torch will work, but on thicker steel, you might need an acetaline fuel rather than propane.

 

[JG Custom Metal Works]

If you have a torch, or a forge, you could just heat the tang and bend it to where it needs to be. Even a small plumbers torch will work, but on thicker steel, you might need an acetaline fuel rather than propane.

That's a good idea, I didn't even think of that. That would probably save some money too.

It looks like 5/16in thick 52100 is not available anywhere so I'll need to either use a different steel or use 1/4in thick stock. Which should i do?

 

[M forge]

I have not found 52100 that thick either. It would be my first choice. A friend gave me a piece of W2 that was 5/16" X 2" so I heated it up and bent it for the drop. It will take a lot more than a plumbers torch to bend a piece of steel 2"x5/16". I used a forge with a TRex burner and had it turned up fairly high. I only forged/bent the handle section of this blade and will stock remove the rest but if your piece is only 2" wide forging the whole thing might be good as I am kinda locked into a design I would like to tweak a bit but can't due to size shape of what I am working with.

I think A2 can be had in the thickness you want.

 

[Camber]

Maybe try Southern Tool Steel.

 

[JG Custom Metal Works]

Maybe try Southern Tool Steel.

No dice from what I could tell.

 

[JG Custom Metal Works]

Hey gents. I've been doing some digging on bevel angles and found this thread:

http://www.bladeforums.com/forums/showthread.php/562593-Chart-of-Blade-Angles-for-Flat-Grinds

The guy made a chart of bevel angles for full flat grinds. On his chart, for a chopper with 2in width and 5/16in thickness, he lists the angle at 4.5 degrees(9 degrees inclusive). For a 2in wide blade with 1/4in thick stock it would be 3.6 degrees/7.2 inclusive. Does that sound right?

 

[carbonsteel928]

This also works https://docs.google.com/spreadsheet...GNMcTRtTGdtTmdtMXNCVmVGYmRaWkE&hl=en_US#gid=0

 

[worldwood]

Great resources guys, thanks for posting them.

I actually paid for an hour of college level trig tutoring months ago just to try and figure out how to calculate these angles. These charts make it so much easier LOL


Creature, in the link you posted its kind of sad to see that thread was locked because, and i quote "The actual angle is irrelevant." according to the moderator that locked the thread. Angle = geometry... SO by that logic the geometry of a knife is irrelevant ?? I sure hope i misunderstand him.

 

[james terrio]

Angle = geometry... SO by that logic the geometry of a knife is irrelevant ?? I sure hope i misunderstand him.

I doubt that's what he meant. Perhaps he was just saying that obsessing over a percentage of a degree of angle isn't very productive - that's my opinion anyway. Of course others feel differently... there are cats in MT&E who spend hours and hours comparing a 5-degree .002" edge to a 5.5-degree .003" one and vice-versa.

Overall geometry and whether or not the knife can take the beating you dish out is what probably matters most, followed closely by weight and balance. All those factors work together in any knife, large or small.

You'll find that some of these comp guys don't sharpen their knives exactly the same all the way down the blade anyway. It may be a good deal thinner and more acute near the tip for fine cuts than it is near the middle or heel for chopping. That pretty much throws math formulas out the window.

Something as specialized as a comp cutter seems a lot like a high-end guitar to me. I can buy an exact replica of Tony Iommi's favorite axe, but that doesn't mean it's going to be comfortable for me or make me sound like him.

It's awesome to have guidelines from experienced cutters and makers, but at some point you just have to work with your knife in your hand and see what happens. If the edge doesn't cut well enough, thin it out some. If it's weak, thicken it back.

 

[carbonsteel928]

I doubt that's what he meant. Perhaps he was just saying that obsessing over a percentage of a degree of angle isn't very productive - that's my opinion anyway. Of course others feel differently... there are cats in MT&E who spend hours and hours comparing a 5-degree .002" edge to a 5.5-degree .003" one and vice-versa.

Overall geometry and whether or not the knife can take the beating you dish out is what probably matters most, followed closely by weight and balance. All those factors work together in any knife, large or small.

You'll find that some of these comp guys don't sharpen their knives exactly the same all the way down the blade anyway. It may be a good deal thinner and more acute near the tip for fine cuts than it is near the middle or heel for chopping. That pretty much throws math formulas out the window.

Something as specialized as a comp cutter seems a lot like a high-end guitar to me. I can buy an exact replica of Tony Iommi's favorite axe, but that doesn't mean it's going to be comfortable for me or make me sound like him.

It's awesome to have guidelines from experienced cutters and makers, but at some point you just have to work with your knife in your hand and see what happens. If the edge doesn't cut well enough, thin it out some. If it's weak, thicken it back.

Well said. Though at times it is necessary to know your angle. For me, when making razors, I need to know near exact angles to make sure that the edge will sharpen correctly since there there is a unique relationship between spine thickness, blade width, angle and edge.