first integral, CPM-3V

JTknives

JTknives

Joined
Jun 11, 2006
Messages
8,651
well to day i milled out my first integral. i cut the material a wile ago but put off the milling. its CPM-3V :D and man did i have to wast a ton of this pricy stuff. right now its just in its hoged out stage. i know the blade is thick but i like a good hallow grind on a thick blade. tang will be drilled out to lighten it. now does any one have a good heat treat formula. the tang and blade are going to get some tastfull file work :)
 

Attachments

  • DSC02051s.jpg
    DSC02051s.jpg
    29 KB · Views: 256
  • DSC02055s.jpg
    DSC02055s.jpg
    26.8 KB · Views: 136
  • DSC02057s.jpg
    DSC02057s.jpg
    45.5 KB · Views: 90
  • DSC02059s.jpg
    DSC02059s.jpg
    40.3 KB · Views: 174
  • DSC02062s.jpg
    DSC02062s.jpg
    54.3 KB · Views: 236
how hard you want it
i run 61 no problem
1500f 5 min soak
2050f 25 min then quench (plate)
right to room temp and then cryo
temper in the morning 400f 6 hours works but if you want to play safe 1000f
crucible data sheets are dead on for me (mind you i know my kiln reads a hair hot when its not )
 
ok its in the oven getten hot. got my cryo tank redy and its comming up to temp. i did change the blade a bit. i put holes in the tang and milled the blade down to 1/8" because it was to heavy.
 
Per Paul Bos:

"Austinize @ 1875 -2000 deg. F ,Hold at temp for 30 min. Air or interrupted oil quench to about 1000 deg. F.then air cool. I suggest air quench. Air quenched from 1950, temper at 950 will give you a R\C of about 61. 3 temper min. You can do a sub-zero after first temper. Two hrs. per temper. Paul."
 
I pulled the foil out of the oven and opened it and in some places the foil stuck to the knife. I removed the blade and did an interupted oil quench then cooled with compresed air hose. I checked hardness and it says 61. Is that correct. Its in the ln now for a 24hr soak.
 
sounds good (i get low temp foil stuck some times when over 2000f)
24 hours is a ton (no harm) i do it over night just cause i heat treat before bed. also lets the kiln get back to 0f by morning (ok 72F)
 
61 sounds about right. It should come up to about 63 with cryo.
Wrap your blade in foil to do the tempering. 950-1000F causes quite a bit of oxidation.
 
im going to temper at 400 for 2 hrs as im not at work now and i dont have axcess to the ht oven. also i would like a very hard blade as its a small blade and im not looking for super impact strangth. now my question is this. my blade has been swiming in the LN for 18hrs and im going to take it out and temper it for 2hrs then dip in LN for 2hr then back to the oven for 2hrs and so forth. so i would end up with 3 LN soaks and 3 tempers ending with a temper. will that help anything?
 
I've never encountered any mention of multiple cryo treatments with blades. Personally, I doubt there is much benefit to be gained after the initial treatment.
 
if the cryo will up the rc to 63 then what am i looking at with a 400f temper, maybe 62?.
 
The CPM3V data sheet doesn't include low-range tempering data, so you will have to experiment. Butch is the only one I known of who does that.
 
3v is tough stuff i have don't that 400f temper and beat the hell out of the blade with out having edge chipping problems
i now feel fine with the low temper temp on most knives in 3v
 
now cucible states that doing a 1000f temper will drop the rc from 63 to 61 but how much drop would i expect with a temper of 400. i would guess maybe .5 of an rc. am i wrong ?
 
Ok i have another problem. I dont know how i missed it. The blade is bent at where it joines the guard. Its about a 1/16" can i safeley bend it straight with a hydraliak press. The blade has had its 3 cryo soaks split up by 3 2 hr tempers. And a file still skates
 
Last edited:
boy thats sucks you might be stuck there
might try the higher temper temp and the press

other wise you might jsut find out how toughf 3v really is. i never found a way to bend it "right" might try reheat treatign it adn bending it before the first cryo while its still warm

cpm154 and 3v (that i have been able to make work ) can be played with out of quench to get a bend out of it but once its is to cryo i would not risk with out temper and once tempered good luck i have flexed 1/8 thick 3v over 1/2 inch (5 inch span) at the "needed fix" and it would just flex and spring back to the set warp
 
I was just worried that I would break it since a file is skating, but you put my mind at rest. I will try and bend it with the hydraulic press at work but if that does not work then o well. I really don’t want to re heatreat it. Ya its all through its 3 cryo cycles (don’t know why, just had the LN so I was like "Why Not") and in for its last temper. it seams that my oven is holding it smack dab on 400 for each of the 3 tempers. I’m just excited to get her done and see what all the fuss is about. might be my favorite high alloy steel. Its weird because its not a gradual bend from base to tip but its just bent right at the base and that points the blade off to the side by about a 1/16. but the blade is straight. might just keep it and make her my daily companion, and make another. how do I get around the bending. I’m guessing it came out of the foil that way as it was laying on its side in the oven and it looks like gravity works just fine on hot steel. I wanted to rest it on its spine but in was in foil. I used the high temp foil which was rated up to 2100. I had the oven set to 2050. Must have just got a hair warmer for a bit for the foil to stick in jest a few little spots but man is foil wrapping the cats pajamas :rolleyes:
 
Could very well have to do with machining stress.

If you took all the material off of one side, then all off the other, it can do stuff like that.

Sharp corners don't help either...
 
Don't attempt to straighten below 400 F .For that steel you could go even higher.
 
well i checked the rc and it ended up being 62. now i'm worried about trying to straighten it, Should i be.
 
You must log in or register to reply here.
Back
Top