small half round file

[Hefty]

As a Tech Studies teacher, I often find broken tools hidden in strange places by students who have panicked and tried to avoid owning up.
Anyway, I've found myself in possession of two halves of a small half round file that a student snapped and stashed in a cupboard. The piece still attached to the tang is only about 2 1/2" long (not including the tang itself) but I thought I'd use it as a bit of a practice piece.
http://i49.photobucket.com/albums/f273/Hefty1982/P1030083.jpg
Can anyone suggest a good design that I could use a half round section for?
I guess with a bit of grinding I can turn it into a good bevel?
Any suggestions would be great.

Jono.

[mayall]

Hay Jono
you could make a japan style knife .which is flat on one side and has a bevel on the other .or if you have a fernice you can flatten it out and make a small caping knife .

[Hefty]

Yeah, I was thinking of a little caping knife. I Haven't got a furnace though.
It's only a little practice job to get a feel for grinding without work hardening etc, so I'll see what I can come up with.
Thanks Mayall!

Jono.

[Sagitarius]

My first thought is a small dagger style blade.

The file might not be thick enough to bevel both sides with the existing rounding.

[jindydiver]

If you make a warnecliff you could bevel one side and just flatten the back. It would make a smallish sushi knife. http://hocho.o-1.jp/product.html
Without the ability to heat treat the steel you are pretty limited to what you can do and how well you can do it unless you have an incredible amount of patience. It wont take much over heating to change the temper of the steel and then it wont hold an edge as well as it could. Also you will be working very hard to grind the hardened steel.

If you fire up the BBQ and get a good bed of coals happening, you know thew sort of fire you melt stubbies in, you can put the file in and just leave it. Next day when the fire is all done you can collect the file and it will be soft enough for you to work it easily and you don't have to worry about how hot you get it while grinding. You will also be able to drill it if you want.

When you have it all finished you just have another BBQ and get that blade good and cherry red, going on orange and quench it in some preheated vegetable oil. Cook in the over for an hour at 220 and you will have a knife that will work well.
Do you do any wood work? you could make a kiridashi (a japanese marking knife) http://codesmiths.com/shed/things/knives/markingknives.htm
I sometimes make these out of scrap pieces and give them away

[forrie]

very good mick was just about to suggest that warnecliff design , i think that would be the best bet for this size of steel, i would be taking advantage of the round shape of the file too as i prefer convex edged knives

cheers forrie

[Hefty]

Cool, thanks guys! I might have to try the bed of coals thing. Would heating with an oxy torch work or would it be too uneven? (I can access one at work)

Jono.

[jindydiver]

If you heat the whole thing up as well as you can with the oxy and then put the steel into a bed of fine wood ash it will cool slow enough for you to work it with files and to drill it.

To harden it you really only need the edge to be working hard and so you can use the oxy (on small knives) to heat the edge till non-magnetic before quenching. It isn't something you should expect to get perfect without practice but it is commonly done. Be aware that you need to get enough of the edge hard for your knife to be useful for years to come, taking into account any steel that will be lost during sharpening.

[Hefty]

cheers Jindy! Alas for now it will have to be another project to tack onto my to do list but something that hopefully I will get to soon.

Jono.