What steel for the first time making a knife

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Tjstampa

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My kids, ages 20 and 17, want to make fix blades. The tools I have are
1.4 inch angle grinder
2.Jig saw
3 1/x30 slow speed belt grinder
4 Reciprocating saw.
5. Drill
6 Propane/mapp torch
7 Home made heat treat forge (firebrick and the above referenced torch)
 
Hoss's suggestion is a good type to start on. Any basic alloy spring steel like 8670, 5160, etc. will be pretty easy to HT with a simple forge.
Other simple steels that are very easy to HT are 1080 and 1070.

You need to add a small welding magnet to the list of tools. You will need it to determine when the steel is ready to quench.
For the steels listed you should be able to use a gallon of canola oil heated to 120°F for the quench.
You will also need something to hold the blade during HT. A pair of the large long handle needle nose pliers from HF work fine. They come in a set of three or four, IIRC. I cut the tips off leaving just 1" to grab the blade. This makes them more like HT tongs.
 
I used 1075 and 15n20 from NJSB a good bit before I got a kiln and was happy with the results heat treating in a forge. 1075 is pretty forgiving if you under or over shoot the temp a little. I have a short and thin 15n20 machete I made years ago and heat treated by eye, edge rolls rather than chips with heavy use but I still use it a lot.

I haven’t heat treated 8670 in the forge, only in a kiln. But it gets recommended for beginners often

Have fun!
 
I will probably order a gallon of Heat Treat oil for when we do the quench. I will probably need a minimum for free shipping depending on where I order the steel and handle materials
 
I'm going to go in a different direction.....

Almost how I started... I think I did this with my third blade?

I recommend you start off with buying a quality HSS Power hacksaw blade.
I buy them new. I prefer Starret.

strip it, and grind it.
They are Crazy Hard, 64-66HRC, probably M2 high speed steel.

You then wont have to deal with heat treating.
There are Many advantages to doing it This way, and few knives will be better.

I can help/talk you through it later(more) if you are interested.

Even though I make knives with a variety of steels, I still believe in the quality of a good HSS blade.
 
8670


better (a bit harder to heat treat)
5160
15n20

Easy to heat treat. Great price and performance.


What to avoid - water hardening steels (relatively easy to work with and heat treat but need better temperature control and a "water/fast" quench) 1095, 1075, W2, W1, etc (great price but harder to heat treat)

Air hardening Steels - A2, D2, 3V, Stainless Steels. Some are harder to work with but no big deal... but way more complicated heat treat (or send off for heat treat, these go right up to highly recommended at that point) Higher price but some are still very affordable. (AEB-L as an example)

Unknown Steels - how do you heat treat? Any good? (waste of time and money)
 
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Daniel Fairly Knives said:
best
8670
1084

better (a bit harder to heat treat)
5160
15n20

Easy to heat treat. Great price and performance.


What to avoid - water hardening steels (relatively easy to work with and heat treat but need better temperature control and a "water/fast" quench) 1095, 1075, W2, W1, etc (great price but harder to heat treat)

Air hardening Steels - A2, D2, 3V, Stainless Steels. Some are harder to work with but no big deal... but way more complicated heat treat (or send off for heat treat, these go right up to highly recommended at that point) Higher price but some are still very affordable. (AEB-L as an example)

Unknown Steels - how do you heat treat? Any good? (waste of time and money)
Click to expand...
1084 also needs fast quenching.
 
Those high speed steel hacksaw blades make AWESOME knives. Much tougher than you’d think and hold onto an edge like grim death. However, you need good grinder skills. All the things that make it great for knives make it hard to work with if you don’t have tools up to the job. I have 2 large blades that are about 0.09” thick. I had a thinner one too. It was 1/16” or maybe even 1 mm. It was MUCH easier to work into a knife.
 
I bought some 8670 for us to work on. Hoping this week to look at scale materials. The hhs saw blades look interesting. How hard is it to cut or drill holes for attaching scales? Do you need to hit those areas with a torch to soften?
 
Stacy E. Apelt - Bladesmith said:
You need to add a small welding magnet to the list of tools. You will need it to determine when the steel is ready to quench.
Click to expand...
Stacy has a good point, this is a great way to determine the right temp without a HT oven.
Another option if you don't have a magnet (depending on the steel), is that regular table salt melts at 1474F, which is close to the proper temp for some steels (IIRC, 1070/1080/1084; 52100(?); O1 as a few examples).
 
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I have experimented with the salt indicator and found it useful for checking a HT oven, but not accurate in a forge. The heating is all over the place in the flames and it may not melt at the same temperature as the blade. The temperature of the atmosphere and heating speed of the metal in a HT oven is much more even than a forge.

A magnet will stop sticking to the blade at around 1415°F. Put back in the forge and heat a few seconds longer (just a tad redder than it was before) ... and quench.
 
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Tjstampa said:
I bought some 8670 for us to work on. Hoping this week to look at scale materials. The hhs saw blades look interesting. How hard is it to cut or drill holes for attaching scales? Do you need to hit those areas with a torch to soften?
Click to expand...
In its original form you can’t cut it with hand tools and can’t drill it without carbide bits. I’ve heard holes can be drilled with carbide masonry bits but have never tried it. The blades I’ve made were hidden tang designs.
 
The Power hacksaw blanks are crazy hard!

Rough cuts with an angle grinder and cut off wheel. Dip steel in water.

I started drilling with carbide drills, but that gets expensive Fast.

I got turned on to masonry drills. They have a small carbide bit welded on. You might have to sharpen them some, but that's the best way.


The very reason PHS blades are tricky are the same reasons that makes them why you should use them.

They take Forever to grind.

(Which means it takes longer to screw them up).

They made me a better free hand grinder, because of All the practice.
Seriously
 
8670 should come in the annealed condition.

Edit: AKS says hrpa🟰hot rolled pickled annealed is the condition it’s sold in.

Hoss
 
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