Stock metal for blades?

[Paul_B]

I was at a car boot sale today and after watching two many forged in fire programmes I started seeing things that could be made into knives.

I'm not going to do it but what can be made into knives if you had the skill? I'm thinking files, metal spikes/wedges, large stone working chisels, large, old pliers, etc could become knives. Anything else you might expect to see at car boots?

I'm just curious to find out from anyone who knows about this as there's always a lot of rusty old tools that are highly unlikely to be reused but are likely to be decent bits of hardenable metal.

 

[Mesquite]

I've seen knives made from old spanners

 

[Deleted member 56522]

I was at a car boot sale today and after watching two many forged in fire programmes I started seeing things that could be made into knives.

I'm not going to do it but what can be made into knives if you had the skill? I'm thinking files, metal spikes/wedges, large stone working chisels, large, old pliers, etc could become knives. Anything else you might expect to see at car boots?

I'm just curious to find out from anyone who knows about this as there's always a lot of rusty old tools that are highly unlikely to be reused but are likely to be decent bits of hardenable metal.

It all depends on the amount of carbon (and other things) in the steel. Generally, the more carbon, the harder it becomes after heat treatment, but also the more brittle. So, as carbon increases it goes from an edge that is easily worn away, to one that is hard but instead of wearing, it tends to chip, or even break. Heat treatment also has a similar effect. The problem with using steel for odd bits and pieces, is that you can't be certain what they are made of.

I think the basic idea is that anything that works as a blade can make another blade. And something big and chunky that has to reduced in size is a lot better than trying to forge weld together small bits into something big.

 

[SoldierPalmer]

It can be done with anything with a high carbon content.

 

[Kadushu]

Saw blades are pretty good.

 

[swyn]

Hoof files from your local farrier are superb.
S

 

[pieinthesky]

Hoof files from your local farrier are superb.
S

Some makes are far less superb than others.
I did do a test on some of the more popular brands a few years ago. If I can find my results I will post them up here.

 

[pieinthesky]

Here you go, I posted this on Blade Forums in 2017 Save Edge and Bassoli seemed to be the most suitable for making knives.


I took 4 different makes of 14 inch farriers rasps and measured the Rc at the tip end and the handle end:

Save Edge 66 Tip 61 Handle
Bassoli 65 44
Mercury 55 41
Hellier 44 39

Next I sawed off the tangs. Except for the Mercury on which I used a cutting disk, the tangs were all soft enough to be hacksawed easily. I used the tangs as I wont need them to make knives and any case hardening is less likely to be present. I filed groves in each tang for identification and ground the surface of each side to remove any case hardened layer.

First I heated them to 825C, soaked for 10 minutes and quenched in oil. Hardness was as below

Save Edge 46
Bassoli 56
Mercury 23
Hellier 18

I then re-heated them all to 840C and quenched in water. Hardness was:

Save Edge 56 - 63
Bassoli 61 - 63
Mercury 50 - 56
Hellier 42 - 58

As you can see I did not get consistent hardness throughout each test piece. I am not sure why this is but I did not take to much time getting a good finish on the test pieces and they were just chucked in a bucket of water all together so quench was probably far from even.

I have made decent knives from the Save Edge and Bassoli Rasps but I do not anneal and re-harden them. I temper to the required hardness and grind them in this state. If you have a decent grinder this is OK except when you come to drill pin holes in the tang. If you stick to small pins 1/8" carbide bits are not that expensive and will go through a hard file OK. Grind off the teeth where you are going to drill otherwise they can deflect and shatter your carbide drill.

Hope this helps, file knives are great fun - hope yours comes out OK