back-yard heat-treating questions

[NickWheeler]

Now I know why guys like me that have been sending Paul blades for such a long time keep doing it...this stuff is frustrating!

I figured for my first heat-treat project, rather than put all the time into a blade...I'd just make a filing jig out of 01 and leave it fully hardened.

Well, I have the little freon tank forge. I got the 1/4" blocks up to non-magnetic and immediately dumped them into a bucket of "junk-oil" My quench oil is a Heinz-57 of oils. There's bacon-grease, olive oil, corn oil, and the majority of it is out of a bucket of crap my dad got for me at work (a bucket containing used motor oil, hydraulic oil, and diesel...big trucks).

I'm thinking the diesel is a bad thing to have in it.

Anyway, I assembled the filing jig and everything went together as it had previous to the heat-treat. My file scated off the edge...I started using it on a knife...and it cracked right in half.

I'm shooting in the dark here.

Any help would be appreciated.

I know fully hardened stuff is brittle, I'm not retarded...but I want the files to scate over the blocks. Thanks

Nick

 

[burke531]

My information says that you have to temper to keep this from happenening a gain if you want to retain the as quenched hardness then temper at 250 nto three hundred degrees.

 

[Bruce Bump]

Nick How are Ya? I think you may have it too hard. Full hard is about 63 for most steels. A file is about the same and they dont flex without snaping. Next time temper it back a little and try it. I have a good sized wooden box half full of screw-ups. Welcome to heat-treat 101. Bruce B

 

[Terry McMaster]

Nick, we will spend some quality time on the road to Mr. Leeson's place tomorrow and I will tell you everything I know about this subject. That should get us to Tacoma!! if I talk slow. The guys are right, you are too hard. We can edge quench this and come up with the right answer. Terry

 

[NickWheeler]

Yea sure, it's always the more experienced guys telling us young dumb guys that we're tooooo hard...

Did I say that out loud???

Nick