Heat treating tips

[Droptine]

Anyone have any tips or words of encouragement for a first time heat treat in a homemade kiln/forge?
the steel is 1080+ from alpha knife supply.
I have no way of telling what the temp is, will the testing if its non magnetic be good enough? Was going to quench in canola oil.
thanks in advance
last thing can I screw it the blade up or will it just simply not be hard if I do not do it right?

JP

[Ray Rogers]

There is a ton of information in this forum on that subject. It is certainly one of the most discussed subjects ever on here so try the Search and see what you can find.

In a nutshell though, yes, non-magnetic will do and the canola oil is fine. BUT, nothing is ever that simple. For the non-mag to work correctly you have to catch the steel just as it goes past non-mag. In other words, you want to quench the steel when it is NO MORE than, say, 50 degrees past non-mag AND you want to catch that temperature on the way up, i.e, don't let the steel go past that point and then try to catch it on the way down, not the same result. Of course, while you are trying to accomplish this juggling act you also need to make sure the entire blade is at the same temp so be careful not to over heat the thin parts. Heating the blade inside a pipe is one way to manage that.

Also, don't forget to heat your canola oil to 100 degrees or so, a little more is OK too but cooler oil does not work as well ....

[Droptine]

Thanks Ray I will do some searching on here. The oven we made is a 6 inch metal tube filled with plaster of Paris/sand mix that we have a bernzomatic map gas piped in.

[Hurley]

I tried the plaster of Paris sand mix once, didn't work so well. Neither holds heat. Better off getting Kao wool or firebrick as a forge insulator. The problems with the plaster of Paris/sand mix are threefold at least. One-the mixture becomes very brittle and will chip in hunks. Two- the water you have to mix the two with must be completely dry, which may take several days. Three- when it's all said and done, the mixture is not a very good insulator. Sure while you maybe able to get it to critical temp (it will take a while which results in using a lot of gas), but it won't hold it there for very long at all. At least that the results I found when doing it.

[Crex]

While the responses posted so far, contain excellent advice, the most important for you to heed is the "search" recommendation by Ray. It is obvious that you have read/viewed just enough to get in over your head.
Reading (and understanding) is your PFD. Best part is it is all here and easily found with just a little effort. Use some discernment and follow the advice of the "elders" here. Got to weed out the misinformation that seems to seep in from time to time.

[Droptine]

Ok i did a bunch of searching and reading and I think I will hold off doing it myself. I'm either going to try and find someone in the KC, Mo area willing to help do it or what are my best options for sending out just a single blade?

[Ray Rogers]

You might find someone in your area who can do it but, if not, Peter's heat Treating will do a single blade. The bad news is, it isn't cheap (about $25 for a single blade, I think). Why not just get yourself some Kao-Wool and re-line your forge? After that, its just practice....

[Droptine]

Will that work...the kaowool?

Also can I screw up the blade or will it just not get hard an I can try again?

[Ray Rogers]

Of course Kaowool will work, its what we all use to line forges. Ceramic wool is reasonably cheap, easy to use, easy to get, and very effective. On a little forge like yours it should take about two minutes to get the wool in there after you get the rest of that stuff out.

Screwing up the blade is always an option so I can't say you won't but 1080 is very forgiving which is why we recommend it so you can start over with it if you normalize it. But, if you're worried about the blade then do what everyone should do when first learning to heat treat in their new forge and that is learn to heat treat in your forge before you try to heat treat a blade. You can rough grind a piece of 1080 so that it has bevels like a blade or just leave it flat but put it through the HT and quench process but do not temper. After the quench it should be hard enough for a new file to skate across it as if it were a piece of glass. If it is, then put it in a vise and break it - wear eye protection and face protection when you do this. Bend the steel until it breaks, do not hit it. If it snaps like it was glass and if the grain inside is gray and very fine texture then you have the HT process about right. If not, keep working at it until you do get these results - most of the key will be having the non-mag temp just right and then getting the blade to the oil at that temp. Once you have mastered that process then its time to do it with a blade that you put a lot of time and effort into ...

[Droptine]

That is great advice and I think will be exactly what I do. I have so much time into this knife I hate to screw it up and it's my first one so I think making one that is not as nice and using it to experiment with heat treat is a good idea.

[Crex]

DT
You are going to be putting a lot of time in a lot of blades before get truly comfortable at getting consistent results. Just expect it.
Ray has you on the right path with the HT and testing. I would suggest that you do your testing with the rough, ground to shape, blade in that you are going to have to learn to deal with thin/thick configurations with an actual blade. Thin areas are easily overheated by the novice. One of the harder things to get right in a forge.
As stated, the 1080 is very forgiving steel, and usually can be redone several times if need be. However, it can be "burned" beyond recovery if you are not reasonably careful when heating the thinner areas. There is a certain point or threshold with forgeable blades steels that once past you cannot recover.
Good luck and keep us posted on how it goes.

[Droptine]

Thought I would share the blade that I do have finished and don't want to muck up. I will start working on another to sacrifice to HT. Thanks for all the advice.

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