Knife from file.

[prarieboy]

Here is a knife fashioned out of a mill bastard file.The first pic is of the shaped blank after after quinching the edge in oil. Can anyone explain why on the very edge the oil dosen't bake on like it does on the thicker part of the blade? This does seem to Me to indicate a good edge as some others that have done this turned out well.
 
This pic is what makes a file knife speacial to some folks!
 
The whole thing.With elk antler scales.
 
C-Yall Bob <><

[kbaknife]

That edge is so hot it will turn the oil into vapor!
In the thicker regions it may sort of have the chance to "bake" on.
That's one of the differences in using oil designed for heat treating and other "oil". OIls designed for heat treating have special additives that control the vapor jacket that is created at the high heats used in hardening steel.
A file is most likely made from steel that needs to go from around 1450 degrees to under 1000 or so degrees in about 1 second.
There may be all kinds of reasons you have what you have, but what I mention is only one of many variables.

[ALW]

Very nice knife.  I tried one very similar to yours this summer.  I think my file was a little smaller though.  I annealed it and ground it to shape.  I was amazed at how soft it got.  Then I heated it to non magnetic and quenched it in warm motor oil.  I really hardened back up nicely, but it warped a little.  I took it straight from the fire to the oil and put it in edge first.  Did you have any problems with the blade warping any?  I'm not sure whether to trash it and start over or try straightening it.  Didn't mean to hijack your thread just trying to learn.  Agan, very nice knife.

Aaron

[Wampus]

Did you draw it any after the quench?  As quenched, most tool steels are very hard/brittle and can easily chip out the edge.  Should be drawn/tempered in an oven for a couple of hours after hardening to relieve some of the stress and draw the hardness back to make it less brittle and prone to cracking.  
Good looking knife you got there.

[d. ward]

Great looking knife.bowdoc

[prarieboy]

Hey Aaron It did warp when I annealed it but straighting in the soft stage was fairly easy. Iwould not try (again learned the hard way) to straghtin one in the hard state.
Wampus As for tempering I have been making 2 cycles of one hour each @ 400 deg.f. That has worked well so far. But I  am old school and believe that if you have a knife in Your hand and need a crowbar put the knife down go get a crowbar! So I have not tested tensil strngth on purpose. Color me chicken and don't want to break somthing I have so much time in! I may grow some cahones some day!
 Thanks to All for the kind words.
  C-Yall Bob <><

[jaynalley77]

Very cool looking knife.

[ALW]

Prarieboy, mine did OK when annealing but seemed to warp when I quenched it.  It was mostly in the handle area but some in the blade part.  I went ahead and did the tempering in a toaster oven the same as you.  Two cycles of 400 degrees for an hour each.  I swear it barely seemed to soften it back up much.  But after that I realized the blade had too much warp so back to the drawing board!  I may try to anneal it again and straighten it out and start over.  I was making this for my cousin from a file I got from my grandfather.  He passed away several months ago (we used to work in his shop alot as kids) and it has some sentimental value.  So I'll probably give it another shot.  Thanks for the help.  Also do you quench with the edge of the blade straight down?  I'm new to this and I thought I read to do it that way to help prevent warping!  Go figure.

Aaron

[prarieboy]

Hey Aaron  I am no metalurgist ! I have annealed some twice to get them to where I was able to drill. Don't know exactly what this does to the chrystals?
 I do try to enter the oil in a straight shot.
 There are some videos on you tube that may help. Green petes I make a knife there are four parts.
 C-Ya Bob<><