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Grayson Knives

Grayson Knives

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Mar 27, 2012
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The purpose of this thread is to continue a dialogue established between Daniel Fairly and myself (an amateur knifemaker) about the continuing journey that is found in the making of knives. Of course anyone is welcome to join this ongoing conversation.

Thank you Daniel for providing the forum, and having the willingness to share your knowledge with others.

-Demetre
 
Good morning Daniel! I hope you're feeling better.

So I'm planning on doing some grinding this weekend, and was reviewing the small pile of blanks formed next to my grinder that are ready for heat treat. I have more than a few options of where to send them, but I'd really like to get into treating them myself.

I'm working primarily with high carbon steels, but will eventually move into stainless. Is there a HT oven you could recommend in the $1,200—$1,500 range?
 
Thanks Xander. Any experience using the 120V version? I'm renting my home at this time, and am not permitted to get a 220 drop in my garage.
 
Personally, no. But it will likely just take longer to get to temp. I don't use an oven.


-X
 
Excellent thread! I love to pick Daniel's brain, there's all kinds of good tips hidden in there.
 
I work only in 1080/1084 and use a gas forge for HT. I have done other steels and achieved hardening, but not optimal, so I stick to my favorite carbon steel.
 
Sure, anything is possible, you just need accurate temperature control. That's the hard part about a forge.


-X
 
Good morning! Awesome thread! :D

Paragon looks the best to me for kilns, after that I like Evenheat

I have a 120 kiln and a 220 one that is about twice as big, my 120 actually heats up faster. That is because it is insulated better. 220 is generally better but no big deal.

If you have a dryer outlet you may be able to make an extension cord for 220. I'll say that that needs to be done properly if you go that route.

Oven Link ---> http://usaknifemaker.com/heat-treat-ovens-and-accessories-c-57/paragon-oven-and-kilns-c-57-168.html

Don't forget you need quenching oil, a fixture to hold the knives (or two), welding or heavy gloves, eye protection, tongs,maybe a leather apron. You can go high end or budget here... canola oil works good for many steels, you can make a tin foil fixture, etc. I have a budget setup as far as the small things go and put my money in my oil and oven.

A lot of the guys use a gas forge to heat treat especially with the simpler steels. I don't know a lot about them.

With some steels you need to get them into temper as soon as possible. You do not want your kiln to cool quickly. (coils break) A second oven may be needed eventually, a toaster oven and oven thermometer will do the trick. With 1084 you will be in no hurry to get them into the oven so worry about that later. Don't put an oily knife in the kitchen oven! lol :D


Great thread idea!
 
cordgear said:
Can you treat stainless steels in a gas forge with decent success?
Click to expand...

Not really but it does depend... as Xander mentioned with proper temp control you can do just about any heat treat. I think there are gas forges that are thermo/pid controlled for temp too. I'll say that would not be common. Honestly I don't know for certain. You need to hold exact temps for long periods of time.

example, heat treat for cpm154 - preheat to 1400, ramp to 1925 and hold for 45 minutes...
 
Thanks X!

Thanks for the breakdown and insight Daniel! So this may sound naive, but what are the precautions to using the oven besides the obvious? Can I have it set up on a workbench in my garage, and place it like I would a toaster oven in the kitchen? Or do I need to set it on the ground, and keep it far away from everything?
 
Daniel Fairly Knives said:
Not really but it does depend... as Xander mentioned with proper temp control you can do just about any heat treat. I think there are gas forges that are thermo/pid controlled for temp too. I'll say that would not be common. Honestly I don't know for certain. You need to hold exact temps for long periods of time.

example, heat treat for cpm154 - preheat to 1400, ramp to 1925 and hold for 45 minutes...
Click to expand...

I see ... I don't think the gas option would fit my initiatives very well. This is great stuff to know, no guesswork!
 
The high carbon steels will either need a fast or slow oil depending on the steel.

Stainless and Tool Steels will need Aluminum plates for quench and stainless tool wrap to protect your steel.

If you get an oven and follow standard heat treat procedure you can go either way right off the bat.You will have to do your homework but it can be done!

If I had to do it over again with just high carbon and stainless I'd get some plates, foil and a couple of gallons of canola oil. Stick to 1084 only as it works great with canola.

The canola oil is debated for a few reasons but is perfect for 1084. For something like O1 it is too fast and probably too slow for 1095.

Oil smoke gets to me when I do a bunch of knives and at least canola isn't too bad. Do oil quenching in a well ventilated area! I keep saying I will go to plates only but really like high carbon steels.
 
LOL! All I have at this time is 1095, and O1 right now. So I would use conventional motor oil to quench those? How often do you change the oil out too?

I believe I saw in a video you were utilizing an old crockpot for your quenching. Is that recommended for some reason, or would any metal container be ideal?
 
Motor oil, ATF, etc are BAD! They often don't perform as needed, and the fumes are highly toxic! DO NOT USE MOTOR OIL!

Canola oil can work for 1095 and a brine quench works well too, but it will make you pucker at both ends hoping you stress relieved it enough, got every last scratch out and its the proper temp!

Preheating oil works best, about 130*F. I often just take a piece of rebar heat in my forge red hot, quench it and stir the oil with it. That gets it warm, depending on how big of a tank you have. 1 gal minimum, 2 is better.

Yes, you can get a perfectly usable knife from 1095 and canola oil, will it be at optimum hardness or perform like a professionally HT'd knife, close but no. You will likely end up with a knife in the 58-59 Rc range.


-X
 
Oh, and that aplies to O1 as well, it just needs a longer soak at temp before quenching, but canola is fine for it. I believe it requires a 20 min soak at 1500-1550*F.


-X
 
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I can type this but I can't post my answer, this is really weird.

edit - lol! that was odd, I simply could not post my response so I snipped it and posted a pic, lol
 
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