File with teeth ground off from estate sale

This is an interest subject Bob. I remember reading somewhere that you can make a lot of edge tools from files, but before grinding them and bending them they should softened up.

The article I read said that to do this softening you can put the file in your kitchen oven at X degrees for X hour(s). I can't remember how hot the oven needs to be or the timing. A search on the net might turn up something.

After grinding, bending etc. the file needs to be heated up with a torch until it's straw/brown color and then doused in water or oil to re-harden it.

I'm going to have a look now to see if I can find anything about the process.

Well I did find one article about making a knife from a file. The file had to be softened first by heating it to a yellow/orange color first in a campl fire, then removed from the fire and left to cool slowly (called annealing). The next step was to grind and sand it to the knife shape and then it was again put into the fire to re-harden it until reaches a light orange color, then thrust into a bucket of motor oil and stirred around for awhile before leaving it to fully cool in the oil leaning it against the inside of the can. The last step was tempering which was again heating to a wheat color with a propane torch.

The info is similar but doesn't entirely match up very well with the article I mentioned above. It would be interesting find out which method is best or if they both work well. I still have the article somewhere. Probably in one of my old turning books. Meanwhile here is the link to the knife making article.

"http://www.woodsmonkey.com/index.php?option=com_content&view=article&id=171:so-you-want-to-make-a-knife&catid=41:how-to-articles&Itemid=63"

I'd bet on the burnisher as well. The steel in a file is normally over 65rc hardness. Carbide, by comparison, is usually over 73rc. Good HSS (high speed steel) used in chisels, drill bits, and plane irons typically might be hardened to about 59 to 62rc. Plain old high carbon tool steel might be around 45 to 47rc. The point of all this is to say that, to be a burnisher, the file metal would have to be harder than the steel you are trying to burnish. Having said that, you can see that carbide would make the best burnisher, but for all but the very hardest HSS tool steel, the file metal would work.

My dad used to sharpen the high carbon blades in his "Red Devil" scrapers with a single cut file, then burnish the edge with a burnisher he had made from an old file. He was a hardwood floor finisher for over 50 years, and he scraped the ends of all the boards where the sander couldn't get to. He must have scraped hundreds of thousands of square feet of oak flooring in his lifetime.

Just thought of one more possibility if only one edge or side is ground smooth. I am a jeweler in my spare time an I sometimes grind the edge off a perfectly good file to make a "safe" edge. That is so I can file right up to a corner where I only want to cut one of the two surfaces.

Here's a couple of pics;