Making a blade from a file in 9 easy steps

Tai Goo

Tai Goo

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Here’s a very simplified version of making a knife blade from a file… not the only way or the best, but should give satisfactory results for newbies and help establish a starting point.

#1. Get a suitable Nicholson file.

#2. Soften the file for stock reduction by taking it up to a black heat (day light in the shade) holding it there for a minute or two and then let it air cool. If you start to see even the faintest glow, take it out of the fire until it goes away and then go right back in. Repeat this process several times at any point prior to hardening, if necessary.

#3. Grind or file off the teeth (especially along the edge).

#4. Grind or file the blade to shape.

#5. Sand the blade to 100 grit parallel to the edge.

#6. 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.

#7. Go immediately to the temper while the blade is still warm to the touch. Temper at 400 - 450 for an hour, (use a good oven thermometer) allow to cool to room temp., and repeat 2-3 times.

#8. Clean the blade off with sandpaper or a water stone.

#9. Sharpen the blade.
 
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You had me at Step #1 Tai.

A question if I may....

You advise to grind off the teeth and I understand that sharp ridges and valleys of the file teeth may present a cracking issue. If I pound those teeth flat during forging, does that accomplish the goal? That's how I made the knife below. Was I just lucky?



 
BB, Looks like you hammered them down, then ground them off.

Like I said, it's not the only way, or the best. It might be a bit more "fool proof", to grind or file them off first, especially along the edge, that's all.

Just trying to keep it as simple as possible... no forging involved.
 
Tai - I forged this near-to-shape from a raw file. The flats were just hand sanded to 800 after heat treat.


Just trying to keep it as simple as possible... no forging involved.
Click to expand...

Yeahh.... some of my my most ambitious failures involved forging, while some of my meager stock removal efforts have resulted in spectacular(for me) successes.
 
I have recently made 2 knives from files using just a bench grinder and an angle grinder to cut it down to size.

1st one
1Asarrived.jpg


second one
bag002.jpg


I used files because I wanted to do a test run to see if I could actually make a knife. I had never used a bench or angle grinder before so I didn't know if I would be able to actualy do it. Also if I made any mistakes (I did) I could mess up a old file I got for $1 rather than mess up steel I ordered.

I learned fom the process and now I will order some 1084 to work on. While the 1084 i will have to get the heat treat and temper down I at least now have an idea of how to grind out the blade.

I just tempered the blade to make it softer then grinded, instead of annealing then re-hardening.
 
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Looks like a good start. :)

There's always more than one way to skin a cat,... usually.

The heat treating parts can be interesting and a lot of fun. That's why I put those in. :)
 
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Not a bad treatise Tai. Not bad at all. :thumbup: I had very good luck with file blades in the ninties. One custmer went through three deer and two hogs without a touch up, and my HT was not as good as your recommendations. I do not poo poo file blades, but I do prefer Nicholsons.
 
Thanks for the easy tutorial. Once my Nicholson goes dull, I may just try it out.
 
Okay, I'm gonna show my newbieness here! Why couldn't you just temper in an over at 400 for an hour or two and then grind the file hard? Wouldn't that be about the same as grinding mono steel hard?

BTW, I love the look of file knives. I browse Michal Morris' website all the time and love the looks of his knives. Those made from old rasps aren't bad lookin' either!
 
Mudbug007 said:
Okay, I'm gonna show my newbieness here! Why couldn't you just temper in an over at 400 for an hour or two and then grind the file hard? Wouldn't that be about the same as grinding mono steel hard?
Click to expand...

I have tried to do that for the last two days and probably 10 hrs oven time total. Hand tools skate off still. I have used a fire pit several times successfully, heating to non mag, then burying in ash or sand. YMMV
 
Good tutorial. Am I the only one who thought it was gonna be first get your file, next get some 1084 or other simple steel, next file away?
 
Thanks Tai, you've summed it up very nicely. :)

Mudbug007 said:
Why couldn't you just temper in an over at 400 for an hour or two and then grind the file hard?
Click to expand...

You definitely can do exactly that. :thumbup: If you happen to have a belt-grinder but don't have any sort of annealing/HT set-up, that's the way to go. Just keep the steel cool while grinding. If you need to drill the tang for pins/bolts, you can spot-soften (not a true anneal, but it will get the steel to a point where you can drill it) with a typical $10 propane torch. Keep the blade in water, heat the part you want to soften to a good orange-leading-to-red, and let it cool slowly. Or just use solid carbide bits at high-speed with plenty cutting fluid.

This is not the best way to make a knife, but it's one of the most do-able for folks who don't have a lot of tools or budget. The file knives I made in this manner blow most Walmart factory crap (including some "big names" I won't mention) out of the water in terms of cutting performance and keeping a fine edge.
xmtgx said:
Good tutorial. Am I the only one who thought it was gonna be first get your file, next get some 1084 or other simple steel, next file away?
Click to expand...
That's the next step in the addiction :D
 
Mudbug007 said:
Okay, I'm gonna show my newbieness here! Why couldn't you just temper in an over at 400 for an hour or two and then grind the file hard? Wouldn't that be about the same as grinding mono steel hard?

BTW, I love the look of file knives. I browse Michal Morris' website all the time and love the looks of his knives. Those made from old rasps aren't bad lookin' either!
Click to expand...

That's what I did on my 2nd knife. Except I heated it at 450 for 1 hour twice.

I kept a bcket of water next to me and dunked it after every pass on the bench grinder.
 
Stacy, It's up to you,... if you think it will help.

Sam, I'm sorry I didn't have time to do a full blown tutorial with pix and all.
 
On the heat sources, step #2 can be done just on an open bed of coals (charcoal) with no blast. You really don't need/want the fire too hot for that one.

For step #6 a good controlled draft with a cherry bed of coals (charcoal) should be fine. If you find it necessary to use a slight blast or forced draft, that's fine too. All charcoal is a little different.

Of course, they can also be done with gas or electric,... which ever suits the situation the best.

Step #7 can be done in a toaster oven, but I recommend putting the blade inside some type of muffle, between baffles or in a metal sleeve to help dissipate and distribute the heat more evenly, and shield the blade from the heating elements.
 
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Hallo Tai, is it possible for you to try to explain some way for me to tell the kind of files i find around? Here in sardinia (italy) i never found a Nicholson, so i'm little concerned about selecting the right file; if are there some hints to look after.
Consider that sellers here have only available k720 (o2), C70 and stainless... no plain carbon to play like w2 or 1080 unfortunatly, so files could suitably jump in for certain projects.

Thank you for your indications!
 
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