Cutters from old files?

[steven c newman]

For small cutters, and some profile planes. Can an old file be used? I have a 1/2" wide coving plane, with such a cutter installed. BTW, it is used Bevel down. They left the teeth of the file in place, to provide a grip for a wood wedge.

[Bill Houghton]

Hard to sharpen, and might be brittle if you hit a knot; but, once you got it sharp, it should be fine.

Years back, a lot of woodturners used to make turning tools from files.

[george wilson]

Files have very high carbon,like straight razors. Even if you draw them blue,they can still be brittle. I have used them for SMALL,special profile wood turning tools. Had one blow up in my face back in the 60's. I took a LARGE file(about 2" wide),and carefully made a very sharp skew chisel with it. As soon as it touched the wood,it broke off,with the sharp end barely missing my face.

These days,with so many cheap files out there,and USA makers going over seas,they might just be case hardened soft steel.

[jackie gates]

I concur on all accounts.. Files are very high carbon and will take a very sharp edge, but are very brittle and will rapidly break with a voilent reaction when placed under bending forces. Also very dangerous if used as cutting tool even when converted into a knife blade. If they are used for others tools they must be properly anealed, to remove some of the brittle nature, also at a loss of the temper and therefore its sharpness. Be careful in this area. Jackie

[george wilson]

Back in the 60's,I read that Spanish luthiers made a LONG handled knife,about 18" handle,from ground down straight razors. I made one,grinding a straight razor until the sides were flat,not hollow ground . I drew it to a full spring blue.

The knife was for carving the heel of a guitar neck. The long handle was for leverage. You carved the heel with the neck laying on the workbench,clamped,with the heel vertical.

I swear,the first cut I took with the knife,and NOT PUTTING MUCH PRESSURE ON IT AT ALL,the razor blade went PING!! It also barely missed my face!! It was VERY sharp,too.

After that,I got some 1/8" spring steel stock and made a new blade,which I still have. It was hardened and drawn to blue also,but is 1080 steel,not super high carbon like the razor.

Remember,I was a young man at this time,and much less experienced!!

[George Sanders]

Thanks for the warning George. I have a turning chisel made from an old file, but my knowledge that files are extremely brittle kept me from using it. Now I know it will go to the scrapper.

[Jim Koepke]

Jake Darvell used to post here a lot about modifications to Stanley #45, #55 and other specialty planes.

One of his post was about making a blade from a file for a Stanley #55.

http://www.sawmillcreek.org/showthread.php?t=41979

He still posts on WoodWork Forums down under. I think there his handle is apricottripper.

jim

[Willard Foster]

You can use the files but you will need to learn how to anneal (make the file soft so it can be cut and shaped) , harden, then tempering. Google A Woodworker’s Guide to Tool Steel and Heat Treating if you care to learn more.

I did put a file into my wood stove one winter day so that the metal was heated to a bright cherry red. I left it in there until the next day. The file was annealed and I could cut and file it. I never did finish making whatever it was I was going to make. The biggest problem I have is heating the metal. The stove worked, but the file was pretty dirty. Not to much of a problem annealing, but I think you need a torch for hardening and tempering.

Bill

[george wilson]

If you go much above blue heat,your metal will turn gray,which is the fully soft state. I heated the file and razor to blue,and they were both still too brittle. What's left?

[steven c newman]

I recall Roy Underhill having a show about this. He was make a cutter to put in a thread ccutter for wooden screws. Used a "weed-burner" for a torch. He had some fire bricks set up like a forge. He had two different ways of cooling the iron, also. I might look up the show and see how he did it. I think he "softened' the file first, shaped the cutter the hardened it back up. Could be wrong.

[harry strasil]

FWIW Dept, old files had 105 points of carbon, 1.05%, new files are only 95, .95%, but some industrial files can still be gotten with 105 points. By the way, Timken roller bearing races are 52100, 1.0% carbon.

[Rick Markham]

Steven, I actually watched that episode very recently online. He annealed it by heating it and then slowly cooling it by slowly moving it out of his little "oven" over a period of hours, once it was annealed he shaped the cutter, and then hardened it (also to blue as George mentioned). (If my memory serves there was no tempering) but it was only a small cutter for inside a wooden screw box. He wasn't using the cutter in any sort of way that if it shattered he could get injured. it was well supported in the wood block too, doubt there was much forces on any part but the cutting edge. Very interesting show actually. Worth watching for sure.

[harry strasil]

FWIW dept, usual soaking time (time needed to heat a piece of steel all the way thru) rule of thumb is 1 hour per inch of material thickness.

[harry strasil]

FWIW Dept. to anneal a piece of steel, bring to its transformation range 1460° (non magnetic) and then remove quickly and bury it in Vermiculite or Wood Ashes till its cool enough to hold, about 24 hours, its often best with high carbon steels to Normalize by annealing a second time.

[george wilson]

Yes,Underhill softened the file,worked it,and rehardened and drew it. this application of file steel isn't going to cause the file to bust in your eye,as will using files for lathe turning tools.

Many a tool has been made from old files. That is from them being the only cheap,available source of tool steel. It doesn't mean it's the best or safest thing to do. You can certainly make something like a knife from a file,but it isn't going to be stuck into rapidly revolving wood. It may snap off if you twist with it,and you could be injured,but not as risky as using it for a lathe tool.

Files are also additionally hardened on their surfaces by cyanide(at least,they used to be). If you do make a wood chisel out of a file,you must grind the teeth off thoroughly to really get rid of this surface hardening,or the edge will wear unevenly due to the harder spots where the gullets of the teeth used to be.