Thread: Turning chisels made from old files

Originally Posted by BlackbuttWA

From experience....Do NOT use files. Unless you know a metallurgist. I stupidly used a file before I bought some chisels, not knowing any different. I had a catch, I was left holding the handle & a very sharp pointed section of file. Even when I cleared the shed to move house I still didn't find the other half.

Was the file tempered and the teeth removed?

BobL has sort of beaten me to the punch (again ).

I have in the past made tools, including turning chisels, from truck leaf springs and the process is similar to using a file for the same purpose.

High carbon steel, that has already been heat treated, has to be annealed before it can be worked on and this is achieved by heating and holding the heat for a period of time. The steel is then allowed to cool very slowly. At this stage the steel can be drilled (not easily though) ground and shaped.

Once in the correct shape the steel is heated again to harden it (cherry red) and quenched rapidly in oil or water. I use oil. At this point it is very hard and very brittle. To be a useable tool it has to be tempered, which means reheating to a relatively low temperature (straw colour for chisels) and quenched once more.

Now a couple of things, because I have very much over-simplified the process. The colours are an visual thing and nowhere near as precise as the oven BobL refers to. The blacksmiths used their eyes (probably without safety glasses) and their skill was in their judgement.

The second thing (I'm getting there), and this is the important part to my mind, a file has all the multitude of cutting edges on it (compared to the leaf spring) and that creates the potential for weakness due to stress. I think this may be why some have had bad experiences with chisels made from files.

I was told a long time ago that to use files the cutting edges should be ground flat first. Clearly this is a lot of work and hardly worth doing, although I do have a file that has been ground perfectly flat for this purpose.

I have never used it.

Just a comment on 's remark about the effete turning of patternmakers (eh... that came out wrong, but I'm sure you know what I mean), a good friend in a former life was a patternmaker and he recounted to me that he worked with a guy who did all the rough turning of large blanks (600mm plus diameter). He said this old bloke used an axe complete with full length handle!

Apparantly he used to hang on for dear life. Those were the days.

Regards
Paul

Originally Posted by Bushmiller

Just a comment on 's remark about the effete turning of patternmakers (eh... that came out wrong, but I'm sure you know what I mean), a good friend in a former life was a patternmaker and he recounted to me that he worked with a guy who did all the rough turning of large blanks (600mm plus diameter). He said this old bloke used an axe complete with full length handle!

Apparantly he used to hang on for dear life. Those were the days.

Regards
Paul

Ah yes! But did he use it in scraping mode or like a skew? We just use a 2 inch roughing gouge.

Originally Posted by tea lady

Ah yes! But did he use it in scraping mode or like a skew? We just use a 2 inch roughing gouge.

TL

I was led to believe he used it like a skew. I also got the impression that the others in the workshop stood well back. He was the only one who performed this task and the rest of the group were very comfortable that fact.

Regards
Paul

I saw a friend using an axe as a skew for spindle-turning. He did it just to demonstrate the principle of the skewed cutting edge. So I tried it, and it's actually quite easy to do. However, ripping into a 600mm chunk on a face-plate with an axe doesn't appeal to me one bit - don't think I'll try that one at home!

Cheers,

Hi Again,
I do mine almost the same as been said, so I will go through the way I was told & would do if I had to.
After selecting the File, I wrap it in some cloth & tighten in the Vice. I then hit it rather hard with a Hammer to Break off the unwanted Part. Say 100mm.?
You then need to heat the whole File to a Cherry Red, then let it Cool on its own, being NO Water at this stage.
Now the Angle Grinder, to take ALL the Cutting Edges Off.
Blackbutt WA, thought it was a bit hard doing all this, but when it has been turned into Mild Steel, it is rather easy to get them off.
I then grind to the Profile I want. Back to the Heating or Tempering if you like, but only the last 2½ in. or 60 mm. You may have to Heat this twice, then as has been said again, Quench in either Oil or Water, when it gets to a Straw like Colour.
I like to take the Corners off as well, & the Polish the New Tool, on the Stitched Cloth Wheel, using Brown, Blue & then Green Rouge for a very high Polish, as I find that this almost stops any Rust Forming.
Well that is more than my 2 sense worth.

It was understandable that patternmakers in the past made their own scrapers for the many profiles that they needed from the endless supply of spent files that they had to hand.

But now, with readily available and relatively cheap* HSS blanks (which will be much better steel for scrapers, whatever the quality, than any high carbon steel file), why bother mucking around with all that annealing, grinding off of teeth, hardening and re-tempering; unless you enjoy doing that sort of thing.

*eg 6mm x 25mm x 200mm HSS blank for $25 from McYouKnowWho

When boxes of old turning tools get donated to the local men's shed I immediately discard all of the home-mades from tool steel and old files. They are just not worth the trouble; if they have been tempered too hard they are dangerous, if too soft they are useless and if they are just right (Goldilocks) they are still not going to keep a sharp edge as long as any modern HSS.

I used a converted file as a skew (1") for a year or so, fortunately without accidents but it's hidden at the bottom of a box somewhere now. I'll dig it out one day and re-use the handle.
I've also used small files for very small spindle mouldings but nowadays, as Neil says, HSS blanks are so cheap I stick to those now especially after I read somewhere that you might think you've ground out the teeth but the weaknesses might still be there.
Cheers,
Jim