I fancy making a small folding knife and I’m sure I’ve seen some talented folk on here who’ve done the same. I was wondering if anyone could advise on the best type of steel to use and where to get it? Ideally I want something pretty soft (annealed?) to work with (in particular I’m concerned about drilling and tapping some small holes), but which I can then quench (to make it hard) and then temper (to make tough). Is that about right? I have a drill press, angle grinder, bench grinder, water stones and various hand tools. I really don’t want to be buying any new tools!

The knife itself will be a short 2″ blade, fairly thick at 2.5-3mm, with a thumb stud, and non-locking. Aspring to be like this, although accepting the first attempt might be a bit rough:

Would be grateful for any wisdom!

Cheers,

Use an old circular saw blade or similar. Files are also a very good place to start yourself.

The only circular saw blades I have are a lot thinner than that, and won’t files will be pretty hard to start with? Could I anneal a file to start, and then re-harden once I’ve shaped and drilled it?

D2 and O2 steels seem to be popular for some of the people I watch on Youtube,

O1 is fairly easy to heat treat with a simple forge or blow torch and quench in Rape seed oil.
and its easy to get in what ever thickness you want.

https://www.cromwell.co.uk/shop/materials-and-maintenance/ground-flat-stock/160202

have made quite a few kitchen knives from o1 and they hold their edge really well.

Good stuff, thanks 🙂

+1 for O1 steel. Sometimes known as gauge plate. Assuming you are using stock removal methods ,whereby you cut the shape out rather than heat it and beat it into shape.
Easy to harden, easy to temper, keeps a decent edge, very prone to rusting though so keep oiled after use.
Have made press tool cropping blades out of D2, as I remember they were sent out for heat treating, but were very, very sharp , although they were horrible to grind. If I were buying a pocket knife ,I’d buy D2 every time. If I were making one in the shed, which I have, a few times, I would use O1 every time.

Have to say that from watching the US competition programs on knife making, what they seem to all do is produce a large bar of steel about 8mm thick, then spend a long time on a rough grinder shaping their knife from that.. So if its just down to grinding, why not get something fancy online and just get grinding.
https://www.ebay.co.uk/i/324192661886?chn=ps&norover=1&mkevt=1&mkrid=710-134428-41853-0&mkcid=2&itemid=324192661886&targetid=938697916926&device=c&mktype=pla&googleloc=1007303&poi=&campaignid=10204066968&mkgroupid=107296203972&rlsatarget=pla-938697916926&abcId=1145985&merchantid=6995734&gclid=EAIaIQobChMIs7emj4fl6wIVciB7Ch2yog5EEAQYAiABEgIixPD_BwE

That eBay auction is for strips of 2 different kind of steels to forge weld together into a piece of damascus.
Good luck with that as a first knife.

I actually made my first knife out of rwl34 but only because I worked at a place with its own heat treating facility.

Point of using 01 is it’s a deep hardening steel that will still produce a good edge even if your temperature is not spot on during heat treating.

Old car leaf-springs are fairly popular in the states for making blades from, should be some available from scrapyards I would have thought.

Car leaf springs have been known to have internal cracks, so if you were forging it into ,say, a machete or similar, the blade could snap if you gave it a solid one into a tree. Having said that, some of the finest Kukris ever made were repurposed leaf springs so I guess its just down to luck .
Plenty of hardenable, knife sized blanks lying at the side of roads with speed bumps. Those little metal wotsits on the road are bits of dead coil spring, but again, theyve obviously snapped off so the internal crack issue still applies.
I think that you can’t beat a bit of 01 for a homemade, home heat treated knife.They even put the temperature and soak time on the waxed packet or you.
Quick tip. Lots of info about getting the steel cherry red flying around. In my experience of making hardened pins, blades, whatever, that isnt quite hot enough. Heat the steel til its non-magnetic then heat it a bit more. If you are going to grind a significant proportion of the steel away whilst finishing, heat it til you get little glowing crackles on the surface. This gets the steel fully hard, but you may have a soft skin as i believe the glowing crackles are carbon in the steel burning away.

Another point for OP.
If you want to shape your blade, grinders are ideal. But ,if you want to have some nice , professional looking bevels on your blade, the easiest way for a beginner is with a homemade bevel-filing jig.
Gough Customs on YouTube have some very good videos detailing the construction and use of this jig.
I made one, it was piss easy, and it works a treat.
Have at it and have fun.

Thanks for the tips. Looking forward to getting stuck in now the nights are drawing in…

Really interesting thread.

As apprentices we used to make scrapers and sharp things out of old files. Like you said – anneal them first then file off the file 🙂 then you’re free to forge, shape and re-heat treat.

Don’t some people also use spanners and keep the handle end looking like a spanner?

If the files are through – hardened, then yes you can anneal, reforge and reharden, but I believe most files are now case-hardened, meaning they have a hard outer skin but a soft, low carbon steel core.
There have been a few old files which I tried to anneal and reharden in order to repurpose into something useful,but no joy.
By the time the steel had got hot enough to anneal, the very thin layer of carbon steel had decarburised and so the steel was now unhardenable.

Waiting for the weather to get colder so I can try a bit of home case hardening, which is turning low carbon steel into a steel with a high carbon, heat treatable skin.
We used to do it with Kasenit before it got banned, but I will be trying out the old pack carburising recipes soon.

Check out the outdoor boys youtube channel, he has made a diy forge and makes all kinds of things including knives etc. A good project was shaping a kife out of a rasp then heat treating and making a handle. Pick up a cheap rasp from q diy shop and give it a go!

I’ve made some useful machetes out of leaf springs.

I was going to bump this today, but someone has.

I had my Fore plane out today, to hone the blade, and sitting looking at it I thought it would cut down into 2 blanks.
Plane blades, or Irons as they’re known are usually made from quality steel, and the one in my plane is made of tungsten steel, though most are lesser, theyre still very good quality and hold a hell of an edge, and one designed to cut hard into hard timbers whilst retaining the very keen edge.
Plus most blades are tapered along their length so you have thin for a tang, and a thicker section for you to grind flat or give it weight front and keep the taper for whatever knife makers do 😆

I’ve just approx thickness of this tungsten blade and its 160mm long with about 2mm tapering down to 1.5mm. Seems thin but this is rigid as hell. as a small knife say 3″ blade I reckon it would be stiff enough.
Sharpness. This is the plane i use for curly grained exotic hardwoods and it whispers across.

Plane irons are plenty cheap, and thicknesses go between the thin, to near 8mm thick on a scrub plane blade(A scrub plane blade is curved rather than flat, takes huge grooves out for big stock removal prior to powered planers)

Finally got round to actually starting this! Got a piece of O1 from Phoenix in Sheffield for £6.

The plane blades/rasps/files is an interesting idea, but when proper tooling stock is so cheap I’d rather skip the extra steps of annealing and flattening. Perhaps for the next project – I think a chunky knife with some of the file texture left on could look good.

If you like texture on the blade, put it over something solid when its red hot and give it a few belts with a ball pein hammer.
Or, you could do something like this once youve hardened it:

We used to do it as apprentices to tart our tools up with using lapping paste and dowelling.