few questions - file to knife

SHOKR

Well-Known Member
i decided to try and make knives out of old files

1 some are so rusty i cant even see the steel, should i clean it before i work or near the end? i want to leave part of the ricasso for looks (i have been suggested diluted acids, but want to avoid that, any other suggestions? been also told vinegar which i will probably try first)
2 i know i will need to anneal them, and i know that would seem crazy, but would an oven do? if not what other ways can i use? torch? heat gun? forge?
3 when sanding, do i sand in one direction or both?
4 any body got anythings else i need/would want to know?

PS: i am doing all that inside my apartment, so the more simple and safe the suggestions the better

thanks
 
An HRc of 57 is hard enough for a usable knife which would leave it rather hard for shaping but, depending on the tools available to you, it could be done. I would say first of all that they will need to be normalized for ease of working, especially if all you have to work with are files and hacksaws. All you will need to do is bring the steel up to non-magnetic, get it just a little brighter, then let it air cool. To anneal you would have to slow the cooling more. You could approximate annealing by heating as above and then sticking it in a container of vermiculite or wood ash. Be certain that they are dry.

As far as a forge goes, you will eventually need one if you are going to do your own heat treating. A kitchen oven will temper simple steels but you pretty much need a forge to properly harden steel. If you want to keep the length of your blade down to 5-6" or less you can make a simple one out of a large metal coffe can, a propane torch, and some refractory material that can be had at suppliers such as High Temperature Tools and Refractory.

As far as other suggestions go I would recommend that you get some books on knife making and read them before you do anything else. Trying to fly by the seat of your pants is a good way to assure mistakes and probable failure and loss of interest. It also makes things a lot harder than what they need to be even if you are successful. The answeres to most of your questions, most that you don't know enough now to even ask, will be in those books. One is The $50 Knife Shop by Wayne Goddard. Another that deal mostly with stock removal is How to Make Knives by Barney and Loveless.

Doug
 
thanks!

i already have these books and others, and actually i'm mostly using power tools, drill press and 10" bench grinder (so far) so i can handle sorta hard steel, and i still to have to figure something out for HT, maybe go to someone with a forge at the beginning

thanks again
 
The only real reason to anneal or soften the steel is if you intend to drill or file it... odds are good you will need to do one or both. Doug's advice is good, heat it to non-magnetic and let it air cool, and it should be soft enough to drill and file after that. A kitchen oven doesn't get anywhere near hot enough, a torch or forge are required. If I'm doing stock-removal on a rusty piece of steel, I remove the bulk of the rust with a wire brush first, as heavy rust will gunk up sandpaper or files quickly. My method using your available equipment would be to remove the bulk of the material with the grinder, then switch over to files to clean up the bevels and overall shape, and then start sanding with a fairly coarse grit sandpaper, maybe 80 to 120 grit to remove the file marks, then 220 grit to remove the 80-120 grit marks. I usually sand lengthwise first, then switch over to an angled pattern to remove those marks, then back to lengthwise, and so on. If you sand in the same direction when you switch grits it is harder to see when you have removed all the previous marks.

Leave about 1mm thickness to the edge before you harden the blade, this helps prevent warps and other nasty things happening in the quench. This extra thickness can be sanded off once the blade is heat-treated. You will only want to finish the blade up to 220 grit or so before heat-treatment... To harden the blade, take it up to non magnetic, plus 50-100 degrees,… usually “cherry red” (daylight in the shade). Hold it there for a few minutes and quench it in fresh warm vegetable oil. Go immediately to the temper while the blade is still warm to the touch. Temper at 450f for an hour or two, (use a good oven thermometer) allow to cool to room temp., and repeat 2-3 times.
 
thats one good detailed guide!!
many thanks GHEzell

btw i only repeat the tempering right?
 
Yep, temper 2 or 3 times... I temper 3 times for 2 hours each, probably not necessary but as long as you do not over-shoot the temperature it doesn't hurt.
 
Just finished mine from an old Nicholson. It's 4.5" long, hidden tang. I did it as Mr Lester & Ezell said.
I took me a while to finish since all i have is just a bench grinder, press drill and set of files.
Heat treated with torch and quench in motor oil.
i did it in drilling site, out of my supervisor's eagle eyes :biggrin:
Here is the pic:
piso....JPG
 
Very nice! Some very good workmanship there.

I like how you kept the original 'maker's mark' intact...:biggrin:
 
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