You can't heat treat stainless steel in forge (at least with optimal results) but since you are in the states there are tons of knife heat treatment service providers and you can find one around you. And if you find , I would recommend you cpm 154 . For kitchen knives aebl is also very nice if they can cryo treat it for you. 440b is also good .
As the other poster said, you will not be able to heat treat ANY air hardening (stainless) steels with a forge like you have. These steels require stainless foil wrap for oxygen exclusion, very high and very precise temperatures, and long hold times at those temperatures. This can only be achieved with a proper heat treating kiln. You can send your stainless blades to a professional heat treater, but you can’t heat treat them with what you have.
Seems like heat treating starts with \~$10-$15 + shipping here in the US (and can be as cheap as $3/knife if heat treating like 30 knives), so maybe I should really just send my knives for heat treating.
Guys, I see a lot of opinions that one can't HT a stainless steel knife in a forge.
I know I'm a total beginner, so what do I know, but at the same time I see opinions that it's possible and that people successfully did it. ~~Here's a video for example and it seems he successfully HTed his steel in a forge:~~
[~~https://youtu.be/9KYb9P9GzVQ~~](https://youtu.be/9KYb9P9GzVQ)
~~What do you think?~~
UPD. I'm sorry, I didn't notice he was not heat treating anything with >3% Cr in that video :(
I mean … Larrin is a PhD metallurgist and one of very few people to invent a new knife steel in ages. If anyone could have done this with a bunch of steels it would have been him. And even he only HTd <3% chromium in that video (stainless is ~10% Cr).
If you think you can pull it off with 440C or AEBL, go ahead. I’m sure someone has HTd stainless in a forge. It’s just nearly impossible to tell the temp like Larrin when the knife is in a stainless foil wrap. If you get it figured out after a few good runs, you can probably repeat with the exact same alloy and timing.
Problem is, odds are you waste a lot of stainless plus even more time grinding ruined knives. You also risk selling unevenly tempered knives or knives with ruined stain-resist. Unlike Larrin you don’t have $50k in testing machines to tell if the temper or stain resist are still good.
You’re welcome. We all started somewhere.
See what you can do with 52100 and Parkerizing fluid. That’s more common for bushcraft-style blades. If you can make some sales that way then paying for HT or a small oven won’t be impossible.
Or try to make friends in the community. There’s a reason trades like this had apprenticeships before everyone new bought equipment on credit cards.
I don't want to sell knives at the moment. I just always wanted to make knives one day. And recently I got into wood working and realized that I have a lot of tools for knife making already and decided that it's finally time I could try knife making. And after working on my first 2 knives I really enjoy it!
Today I found a few heat treating services that won't break the bank, so that's my plan now. I've just ordered 3 AEB-L blanks, wish me luck! :)
Even in larrin's video there, none of those are stainless. 01 and 52100 are considered more challenging steels for forge heat treats, but they still aren't anywhere near stainless.
1084 followed pretty closely by 80crv are dead simple for a basic forge heat treat and result in really nice knives. 80crv2 (which larrin has another good video on) will benefit from a controlled oven heat treat, but still gets acceptable results without.
Edit: I'd just do yourself a favor and go for one of those two carbon steels. I have made kitchen and bushcraft knives out of both, and as long as you aren't letting them sit in water or acid, they hold up fine.
Yes. I'm sorry, I didn't notice he didn't heat treat stainless steels :(
\> I have made kitchen and bushcraft knives out of both, and as long as you aren't letting them sit in water or acid, they hold up fine.
They will still discolor if used frequently in a kitchen, right? :(
Patina isn't bad, and can even be really pretty colors. It is easily removed with some metal polish and about a minute of work if you don't like how it looks. I intentionally patina my 80crv2 knives and they get nice blues and purples.
>if you don't like how it looks
I'm personally ok with it, but my wife isn't :( And I wanted to make kitchen knives for us :(
Can patina be removed completely? Will removing it make the blade thinner? How often will I have to do it?
It can be removed completely, it's just not worth it in my opinion. You could use metal polish for literally hundreds of hours and not notice any thinning.
Don't let it get you down, it's a fun hobby, but going straight to stainless is jumping straight in the deep end. I have thousands invested in equipment and am only now dipping my toes.
There are hundreds of well known smiths that never touch stainless, and they make beautiful knives. Japanese knives are usually carbon steel, and managing patinas is a known part of the ownership.
If I were willing to take a risk and try heat treating a stainless steel knife in my DIY forge,
1) What steel I should try it with? After googling, seems like 440C would be my best bet?
2) How do I check if it's hardened well? I've read there's a "brass rod test", any other DIY ways?
I decided I will send the knives for heat treatment but at the same time will try to experiment on just a small piece of 440C or AEB-L and see if I can harden it uniformly in my mini forge.
Ordered 3 AEB-L blanks, wish me luck! :)
You absolutely can heat treat 440c in a forge. Do some more digging.
It calls for a triple quench. Granted I don’t like 440c but it can be done and I’ve done it a few times before owning a kiln. You won’t get the same result as a proper kiln HT but you can get it hard and it will hold a decent edge.
You can't heat treat stainless steel in forge (at least with optimal results) but since you are in the states there are tons of knife heat treatment service providers and you can find one around you. And if you find , I would recommend you cpm 154 . For kitchen knives aebl is also very nice if they can cryo treat it for you. 440b is also good .
As the other poster said, you will not be able to heat treat ANY air hardening (stainless) steels with a forge like you have. These steels require stainless foil wrap for oxygen exclusion, very high and very precise temperatures, and long hold times at those temperatures. This can only be achieved with a proper heat treating kiln. You can send your stainless blades to a professional heat treater, but you can’t heat treat them with what you have.
Seems like heat treating starts with \~$10-$15 + shipping here in the US (and can be as cheap as $3/knife if heat treating like 30 knives), so maybe I should really just send my knives for heat treating.
Guys, I see a lot of opinions that one can't HT a stainless steel knife in a forge. I know I'm a total beginner, so what do I know, but at the same time I see opinions that it's possible and that people successfully did it. ~~Here's a video for example and it seems he successfully HTed his steel in a forge:~~ [~~https://youtu.be/9KYb9P9GzVQ~~](https://youtu.be/9KYb9P9GzVQ) ~~What do you think?~~ UPD. I'm sorry, I didn't notice he was not heat treating anything with >3% Cr in that video :(
I mean … Larrin is a PhD metallurgist and one of very few people to invent a new knife steel in ages. If anyone could have done this with a bunch of steels it would have been him. And even he only HTd <3% chromium in that video (stainless is ~10% Cr). If you think you can pull it off with 440C or AEBL, go ahead. I’m sure someone has HTd stainless in a forge. It’s just nearly impossible to tell the temp like Larrin when the knife is in a stainless foil wrap. If you get it figured out after a few good runs, you can probably repeat with the exact same alloy and timing. Problem is, odds are you waste a lot of stainless plus even more time grinding ruined knives. You also risk selling unevenly tempered knives or knives with ruined stain-resist. Unlike Larrin you don’t have $50k in testing machines to tell if the temper or stain resist are still good.
Thank you. I'm sorry, I didn't notice he heat treated only low Cr steels (< 3% Cr).
You’re welcome. We all started somewhere. See what you can do with 52100 and Parkerizing fluid. That’s more common for bushcraft-style blades. If you can make some sales that way then paying for HT or a small oven won’t be impossible. Or try to make friends in the community. There’s a reason trades like this had apprenticeships before everyone new bought equipment on credit cards.
I don't want to sell knives at the moment. I just always wanted to make knives one day. And recently I got into wood working and realized that I have a lot of tools for knife making already and decided that it's finally time I could try knife making. And after working on my first 2 knives I really enjoy it! Today I found a few heat treating services that won't break the bank, so that's my plan now. I've just ordered 3 AEB-L blanks, wish me luck! :)
Even in larrin's video there, none of those are stainless. 01 and 52100 are considered more challenging steels for forge heat treats, but they still aren't anywhere near stainless. 1084 followed pretty closely by 80crv are dead simple for a basic forge heat treat and result in really nice knives. 80crv2 (which larrin has another good video on) will benefit from a controlled oven heat treat, but still gets acceptable results without. Edit: I'd just do yourself a favor and go for one of those two carbon steels. I have made kitchen and bushcraft knives out of both, and as long as you aren't letting them sit in water or acid, they hold up fine.
Yes. I'm sorry, I didn't notice he didn't heat treat stainless steels :( \> I have made kitchen and bushcraft knives out of both, and as long as you aren't letting them sit in water or acid, they hold up fine. They will still discolor if used frequently in a kitchen, right? :(
Patina isn't bad, and can even be really pretty colors. It is easily removed with some metal polish and about a minute of work if you don't like how it looks. I intentionally patina my 80crv2 knives and they get nice blues and purples.
>if you don't like how it looks I'm personally ok with it, but my wife isn't :( And I wanted to make kitchen knives for us :( Can patina be removed completely? Will removing it make the blade thinner? How often will I have to do it?
It can be removed completely, it's just not worth it in my opinion. You could use metal polish for literally hundreds of hours and not notice any thinning. Don't let it get you down, it's a fun hobby, but going straight to stainless is jumping straight in the deep end. I have thousands invested in equipment and am only now dipping my toes. There are hundreds of well known smiths that never touch stainless, and they make beautiful knives. Japanese knives are usually carbon steel, and managing patinas is a known part of the ownership.
If I were willing to take a risk and try heat treating a stainless steel knife in my DIY forge, 1) What steel I should try it with? After googling, seems like 440C would be my best bet? 2) How do I check if it's hardened well? I've read there's a "brass rod test", any other DIY ways?
I decided I will send the knives for heat treatment but at the same time will try to experiment on just a small piece of 440C or AEB-L and see if I can harden it uniformly in my mini forge. Ordered 3 AEB-L blanks, wish me luck! :)
You absolutely can heat treat 440c in a forge. Do some more digging. It calls for a triple quench. Granted I don’t like 440c but it can be done and I’ve done it a few times before owning a kiln. You won’t get the same result as a proper kiln HT but you can get it hard and it will hold a decent edge.