Heat treat knives made from files?

BruceM

Well-Known Member
Hello guys,
I just bought some older USA made hoof files/rasps to make some knives out of. Never tried one of these yet. Do these need to be heat treated like other blades or are they ok as-is? I will post some pics of the build once I get started. Thanks for the help.
Bruce
 
You probably don't want to work them in their current temper, it can be done but most people anneal them first then work them and re-heat treat them.

Edit: Looking at your question again I thought I'd better clarify, in their current state they are most likely too brittle for a knife blade. If you was to work them in their current state you would want to draw them back to a more knife friendly hardness.
 
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If you are going to use stock removal method you will probably want to anneal them first then they will be ready for you to cut or grind.
If you are going to forge them you probably won't need to anneal them.
good luck, post some pics so we can see how it goes
 
Bruce
You can anneal and re-ht, trouble is you dont know exactly what steel you have. I have made several from a file, I just put them in the oven starting at about 400 and draw the temper down some. Then I grind just as I would for a blade post HT, being careful to keep the blade cool while Im girnding

Good Luck

Sean
 
How long to anneal?

Sean,
Does the oven temp stay at 400? How long does the material need to be in the oven?
Thanks for the help.
 
Sean,
Does the oven temp stay at 400? How long does the material need to be in the oven?
Thanks for the help.

Bruce,
Some guys temper files at 375 but I have had good luck at 400, yes the oven stays constant, leave it in for 1 hour let it cool and put it back in for another hour. It should turn a nice straw color.

What you are doing is drawing some of the hardness out of the file, it is much too hard in its current state.

Here is one of my first file knives, its a little fella. I've used the method above and made several all of them came out great.

102_1087.jpg
 
Files can be a hit and miss proposition. The first thing you need to consider is that a lot of modern files are case hardened, and if this is the case with the files your using, its a wasted effort to produce a blade from them. About the only brand of file that I am sure is not case hardened these days is Nicholson. That is the ONLY brand that is 100% non case hardened. Many of the companies will make a run of case hardened files, and the next batch may not be, depending on the steel the company can acquire. I know that sounds hokie, but that how it happens.

Now thats been said, and IF they are "good steel", it would be a real bear to work them without annealing. Its also likely that if left as is, they will be far too brittle in something as thin as an edge cross section.
 
Files can be a hit and miss proposition. ...About the only brand of file that I am sure is not case hardened these days is Nicholson. That is the ONLY brand that is 100% non case hardened.
Now thats been said, and IF they are "good steel", it would be a real bear to work them without annealing. Its also likely that if left as is, they will be far too brittle in something as thin as an edge cross section.

Bruce,
Ed is absolutly right, I was assuming that you may not have the equipment needed to anneal and re-HT. (i.e. a forge etc.)
 
Thanks for your input guys. Files are in the oven now for the second round. I'm anxious to see how they are when they come out.
Bruce
 
Work in progress- file knife

The files annealed well, thanks again for the help on that guys.
Got started on one just to see how the material worked. Will post more when I get a chance.
 
Looks like you are off to a great start!! I really like file knives.
Just curious , did you fully anneal them or did you just draw the temper @ 400 degrees?
I would imagine they would still be somewhat hard on your abbrasives only having been tempered.
 
Chip,
I did the 'ol double draw, 400 degrees for one hour let them cool then did one more cycle. Seems to work pretty well on these files. As far as being hard on abrasives, I did learn one thing. The course side of the file is really hard on abrasives, those points really kill a disc. I went to the belt grinder after I smoothed the surface on the 12 inch disc. The next one I hit the course side with the angle grinder first and that helped a ton.
Bruce
 
Many, but not all, of these are made from 1095 steel which is a simple, low alloy, high carbon steel of APPROX. .95 Carbon. That can be very approx. depending on the maker of the steel. Regardless, I take these and put them in my coal stove where they come to red heat for about a half hour and then I put them in a porcelain tray full of Perlite from the garden store. Perlite is expanded mica and is insulative so the steel cools slowly and becomes fairly well annealed. You can then grind it and shape it and when you heat treat it again you can do a couple of different things. One is bring it up to red heat to just where it loses magnetism and quench it in brine. You can quench it in other things as well but brine works well for 1095. Then temper at 400 deg. F in the toaster oven and let cool. Should be a good process to start with but you can fool around it with it from there.

Howard
www.theperfectedge.com
hschechter@theperfectedge.com
 
Hello Howard,
Thanks for the tips and info, very helpful. Hopefully I'll get a little more shop time this week and get them done.
Bruce
 
Bruce they are looking great !! Got any ideas for handles yet? Since you did not fully anneal and if you were careful not to over heat while cutting and grinding the blade "might "be ok as is,but I think I would normalise for 2 or 3 cycles and harden anyway. keep the pics coming. Good luck
 
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