Do Knifemakers Know How to Heat Treat?

I watched several "How To" heat treating videos to find out if people know what they are doing. I have links below for resources on how to thermal cycle and how to heat to heat treat in a forge if you want to learn more. Or read my book which covers everything.

00:00 Intro
00:19 Real Engineering
08:12 Outdoors55
14:53 Walter Sorrells
20:11 Red Beard Ops
29:16 Bell Blades
32:23 DIYeasycrafts
38:01 Outro and Summary

[OUTDOORS]

Thanks for the tips! Most of the heat treatment knowledge on these videos was gained before your book came out, and there was no real source of what was actually going on. You would read one thing from a supposedly reputable source (places that sold the steel perhaps), and then read something else contradictory somewhere else. I still hear people say to only heat treat during a full moon🙄 So thanks for the book and knowledge gained👍 Id like to hear your thoughts on a video i did following your heat treatment protocol for 1084 and comparing that to purposefully bad heat treatments at the same rc hardness. Anyway, thanks for writing the book its really helped👍

[gmacka]

18:00 “I’m not crazy”!
That made me laugh. My wife just glanced at me, gave me this look.
Lol😂.

[lindboknifeandtool]

“Metallurgist reacts” is a great concept 👍🏻

[RRINTHESHOP]

Dr. Larin, I bought your book Knifemaking Engineering (Excellent, anybody who is making knifes should read.) I have watched dozens of YT videos from YT knife makers. I am not ignorant it the subject of heat treatment and working with metal. I am a retired Marine Engineer. I have felt that most of the YT knife makers are quite ignorant on the subject of heat treating there blades. This week I forged 3 blades from 52100 material, today I heat treated the blades as per your suggested recipe for 52100. This worked perfect, the blades are about 62 Rc seem to be stout and hopefully tough. There was zero scale (wrapped in St/St foil) and zero warpage. I am sure they will take a very sharp edge and be a tough blade. Thank you for your great videos and research you do in the area metallurgy. I hope to make some blades from Magna Cut one day. Well done keep up the great work.

[althesmith]

You can't go wrong by watching any of Walter Sorrell's videos. I don't agree with him 100 per cent on everything but nobody does- get 5 smiths in a room and you'll get 6 opinions. The man has a solid knowledge base and is good with sharing it.

[MatrixCoreteam]

A fellow metallurgist here. I work in a fairly large carburizing heat treat department. I agree with your comments about 13:00 in on the thermo cycling. The grain size change that occurs during the normalize cycle is mostly accomplished with the first normalize and with the subsequent quench. The lower temp reheats are going to affect the carbide vs retained austenite structure. In my business, we want retained austenite instead of carbides, so we quench from a higher temp and try to stay out of the carbide forming temps for extended periods of time.

On the quench oil at about 13:45. The temp of the quench oil is important for the quench speed. We want the oil at the correct viscosity so it will carry away the heat at the required speed. Cold oil is not going to quench as well or as evenly. Uneven quenching leads to distortion.

[HonkyKong]

Everybody caters to knife makers. Chisels and hammers are pretty cool too guys so could someone make a book for us lowly tool makers? I promise all five of us will buy it.
Seriously though, Doc you rock! I have been confused as crap on this heat treating thing since everyone kinda does what they were taught instead of what is right. I look forward to getting your book and hopefully applying what I learn to my future projects. Thanks for making my world a bit better by sharing your knowledge.

[lando]

I used to weld and have some basic metalworking knowledge and wow was I in the stone age. Somehow never really thought about this area of science, which is surprising because I love metal and enjoy spectating science. Before your videos I guess I sort of just had a slightly magical mindset to how it all works to put it simply.
However, reading the comments though I'm kind of shocked to find this sort of info is new to the top pros in the field too. It seems I'm not alone in still looking at this with sort of an iron age mysticism lol.
Glad the fields are merging. Thanks for your videos, you rock.

[twocrowsblades]

Great video, like I’ve told ppl YouTube can teach u how to do something but can also teach u many ways to not do something.

[Monkeys]

Thank you for making this video! There is a lot of unnecessary steps and myth in knife making and forging. You have help us eliminate a lot of unnecessary things that we have to do.

[stormiewutzke]

Never say you aren't crazy.

Walter is a good dude. He doesn't get super technical but he is a good teacher and seems like he would be fun to have a beer with.

[jonduncansakurawallknifegarden]

Thanks for making more stuff for us to rewatch and study, Mr Thomas. You are a backbone of this community in many ways and a reference for the rest of us that have interest, but don’t work in your profession. This is good for the rest of us. Thank you. Great stuff.

[ddSavant]

I think it’s safe to say you fully geek out when it comes to metallurgy.

And it’s delightful to watch.

Cheers!

[thaknobodi]

I agree the first video went off the deep end for no reason. Flexing.

[upknife]

Great video! This was my biggest concern going into knife making, there was so much theory and marketing but very few really well documented sources, I am an engineer and really wanted datasheets and hard evidence. Your publishing has been such a well needed reality check to the knife community, so Thank you!

[protectthetruth]

More videos like this, please, please and thank you! I like hearing you react to these other creators methods, I'll listen and hear them and think "that makes sense" then you suddenly correct them and I think to myself, "that makes more sense", appreciate the video, old but gold. 🙏🏻

[nnnnnie]

45 years ago I worked with an old blacksmith in Thailand. Nothing fancy but he beat old truck springs into working knives. Charcoal forge, edge hardened in water. He made good stuff and was very particular in what he did. He was very careful about the quenching and tempering, All was done in a continuous manner after heating. I wish I could go back to that time as I've learned a lot since then.

[zionpsyfer]

Fascinating breakdown from the perspective of someone unfamiliar with the process. Very much appreciate the knowledge given and the corrections being nicely done rather than brutal. Thanks for sharing and thank you for Magnacut!

[jacksin]

Thanks for debunking and clarifying, once again, Larrin. Youre a huge asset to our community.

[DamianBloodstone]

Finally a nerd I can understand about steel. I don't know a lot about heat treating (stages of crystalization I understand). When I saw your vid on the subject I needed to take a look. You showed all the failures I've seen before in these types of vids and pointed them out. (We aren't in the realm of metal magic anymore. Use a temp gauge or stick.) Now I'm off to watch you do it right. (I'm a knife nerd but have never made them. I can tell you about the things you speak of about the metal stages and why they fail when looking at the metal.) Thanks for sticking to the science of it.