Lately i have been thinking about buying a kiln. Right now i have a gas forge with a muffle pipe and a thermocouple, and it is passable for simple carbon steels, but nothing more complex. Right now i am weighing the benefits of having my own kiln, (convenience, speed, accuracy, and the ability to use a wider range of steels) with the fact that it would run me about $2000+. When you factor in heat treating costs, and shipping costs, i figure that it would not break even that way until around 150 knives. The second issue, is that without a proper hardness tester, even using a tried and true heat treat recipe is still not a guarantee that the process was a true success. The need for a hardness tester pushes this up to a cost of likely $4000+. I have been watching kijiji for ages looking for either of these items to show up, but so far no luck. I see lots of pottery kilns, but that still isnt really a viable option due to the top loading aspect, and the lack of proper heat controls. For simple steels, it could be made to work, but so can an accurately controlled forge. I also see the odd fixed temp glass kiln, which form wise is more useful, but the single high temp makes them mostly useless as well. What got me looking into this again, is a recent request for some kitchen knives in stainless. Since i cant do them myself, i would have to have someone do them. The fact that they wanted them for Christmas which is only 4 weeks away, means there is virtually no way i can do it, even if they were all ready for heat treat today. If i had a kiln sitting in the shop, this wouldnt be an issue. Im just not sure if its a $2000-$4000 issue. I guess what i am wondering is how many of you have purchased your own kiln and how beneficial you think owning one has been. Or if someone wants to meet up and heat treat some CPM154 or AEB-L in a week or two haha
That is exactly why I made my salt pot. I cost me virtually nothing and works way better that a kiln for heat treating.
A salt pot would be an excellent option @FORGE i just dont know if i have the confidence in my skills to build one. Now if someone was building and selling a salt pot in Canada, that would be one hell of an option . For carbon steels i cant think of a better system than a PID controlled salt system. No scale, no decarb, and a far more stable and even internal temperature. My only concern would be for complex stainless alloys, as i know you had mentioned before that the molten salt gets a bit violent and scary around the 2000 degree mark. Not that you would likley be interested, but just out of curiosity, how many loonies would a guy be looking at to pay someone like yourself to build one of these ready to function?
Well with all your connections, I am sure you can find a piece of 4 in. diameter stainless pipe for the inside, a piece of pipe or tubing for the outside shell (about 12 in. diameter ) some cerwool and burner (nothing fancy) a little welding and you are in business. I forgot you need a propane regulator, voltmeter that will read temperature and some KCL (Potash) which I happen to have 3 bags off. Putting a PID controller on the is a waste of time and money. I suppose if you we heat treating everyday and doing hundreds of knives it would be a benefit.
I may have to seriously look into this. The salt isn't as issue as my brother works at the mine as does half my hockey team. I have regulators, thermocouple, etc. May be time for me to start tracking down some pipe. If I built it correctly I could likely make it interchangeable with my current forge burner and hose setup.
Brandon the KCL you have to use is only manufactured at Mosaic Belle Plaine plant. I tried getting it from PCS and they don't make it.
Ok good to know. Right now i can screw with the air and fuel mixture and pressure and typically hold consistant muffle temps within 5-10 degrees but a salt pot would still totally be worth it for the lack of blade cleanup and even heating alone. I was pretty sold on that method after seeing how clean that last batch you did for me came out.
I made my own electric heat treatment oven back in 2013. It has been indispensable. It cost me around $300 to build and I sourced most of the parts from Canadian suppliers. It's cheap and safe to operate, heat treatment on demand, worth every dime. Can also use it for annealing and tempering. As for the hardness tester, I grind bevels post heat treat and one gets a feel for hardness by how long a ceramic belt lasts. Not exactly scientific but so far no complaints. Dan
