Plasma cutter

stabber

stabber

Knife Dealer Extraordinaire
Has anyone used a plasma cutter to cut out the blades from a huge piece of steel? I got a 3 foot across diamond saw blade that is decently thick. Probably L6. My buddy has one of those portable plasma cutters that works very well. Just that it leaves a little "slag" by the cut.
 
You could do that or use a torch. Just remember to leave a bit of extra to grind away. And the edges will be nice and hard. Fun grinding.huh1
 
Had some blanks cut by a plasma cad once. It took forever to grind away the slag. I would try using a hand grinder and cutoff wheel to cut it up.
 
Where the torch or plasma heats the metal enough to burn away the kerf it will also burn out the carbon so be sure and make the blank big enough to grind wasy all of the heat effected area. Either do like Murph said or just send it to Great Lakes Waterjet.
:haha:

It very well be just mild steel. If it is a diamond blade why would they need to use L6? Same thing on carbide tipped blades.

Better yet, if you want to make knives out of L-6 just get it from Aldo. After all, how much is your time worth?
 
Probably not L-6 but worth giving it a try. I've just had bar stock cut from saw blades with a plasma cutter. Hope your friends plasma cutter is powerful enough to handle the thickness of the saw blade. Like what was already mentioned there will be a good deal of slag to grind away. Best to use an angle grinder to remove the big stuff.
 
I agree with Ray....it's VERY likely NOT L6. I had a construction company who wanted to bring some of those type blades to me, so I could build knives for them...after having it tested, it came back as 4130...nothing that would make a decent knife blade.

If these blades are the diamond toothed variety used for cutting asphalt and concrete, it's a safe bet they are either 4130 or 4140....neither will make much of a knife.
 
OK, Scrap this idea! ;-)

Makes sense about the Heat issue. Was just kicking an idea around:bud:

Yes Ed, it was used for cutting in the highway department so I guess it's good for nothin:D

Wayne, Who's Aldo?:confused:>>>>>>>>>>>>:p

Thanks Dave, ray & Murph2thumbs
 
EdCaffreyMS said:
I agree with Ray....it's VERY likely NOT L6. I had a construction company who wanted to bring some of those type blades to me, so I could build knives for them...after having it tested, it came back as 4130...nothing that would make a decent knife blade.

If these blades are the diamond toothed variety used for cutting asphalt and concrete, it's a safe bet they are either 4130 or 4140....neither will make much of a knife.
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Ed, I to was thinking 4100 type of steel. I've collected a good number of old lumber mill saw blades and I'd say maybe 20% if that are L-6. Much better chances of the modern saw blades being the 4100 type.
 
Where do you get them tested and what does it cost?

I have access to a LOT of saw blades of varying sizes and have not given them a second thought. If I could test them inexpensively it may be worth it to get a stock of L6 or 15N20.
 
I haven't used my plasma cutter for years. When I did I was pleased. I just used an angle cutter to clean up and profile. Now its forging, you know with a press, trip hammer and a rolling mill. Oops forgot the anvil.
 
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Bob,

I have a friend on the west coast who is a retired aerospace employee who does testing for me. He has asked me not to give out his name, but I can tell you that he only charges me $25 per sample.
 
Bob Warner said:
Where do you get them tested and what does it cost?

I have access to a LOT of saw blades of varying sizes and have not given them a second thought. If I could test them inexpensively it may be worth it to get a stock of L6 or 15N20.
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Bob, I had a friend that worked for a steel mill a few years ago that would test the steel I sent him but he is now retired with failing health. I seem to recall Chuck Bybee with Alpha Knife Supply saying he had someone that would test steel. Not sure if he offers the service now but wouldn't hurt to check. Here you go: http://www.alphaknifesupply.com/
 
Thanks guys. There is quite a variety of blades stacked at this guys place and it would cost me a fortune at $25 each and would probably be worth just buying new. If they were all the same it would be a good idea.

Thanks anyway.


Bob
 
Wouldn't drilling the blades tell you if it were mild(4100-30) or much tougher to drill L6?
 
Phil Willson, a great maker and knife writer, started using CPM steel years ago and we can thank him for our current usage of the CPM steels.

One time when we were talking, he told me about his first times using CPM420V. The only way he could purchase the steel was by buying big thick slabs and used a plasma cutter with good results. I take from our conversation that it was his last hope of cutting the big slabs at the time.
 
LOL, I'm only asking. Inquiring minds want to know. I'm sure others may want to know as well.
I figure with the right ingredients, Maybe this chicken salad will be great. LOL
Denny Eller said:
Ricky, you can't make chicken salad out of chicken $#!&.
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ya i think this may by mild steel. do some test cuts. to get the feel of rthe tourch. and to set the amps and gas pressure.i have used plasmas for years. we used shop air , 80 pound min. make shoure start /stop is away for materal you want to use. as this will leave a hole larger than the kerf.same thing if you stop/ start anywear along the cut.first i would cut a piece off the blade and get it checked out. to see if can use it. i hope some of this will help darryl
 
http://img842.imageshack.us/img842/4523/dscf1162.jpg
i don't know if the picture will work but it is of some fillet knives that i thought i would do out of some saw blades from a saw mill that a friend gave me( except for the 2nd one down, it's 15n20) . He told me that they were very close to 8660. I operate a cnc plasma at work where I can cut anything carbon steel from 3" thick down. I cut these with a 30 amp tip and I didn't do any grinding prior to this picture. I also heat treated these (heated fully in salt bath and edge quenched in 120 deg parks 50) I wrote the HRC numbers next to the circle with the hardness tester dimple inside it. You can see that the hardness was measured very close to the edge. I also broke one in two before tempering and the grain was very fine and even all the way accross. I was very happy with the results. can anyone tell me though why there is so much difference in the hardness on the spines of some when they were all done the same way? Thank you.
 
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