Hey craftsmen, l have been a knifemaker for many years. Up till now my knives have been limited to high carbon steels (1080, 1095, 5160) using my forge for heat treating. I'm wanting to broaden my horizons using more exotic steels and stainless. I can't seem to find ANY plans for making a suitable heat treat oven. Plenty of videos, no plans. Can anyone help me out? Thanks.........Maximus.
need heat treat furnace plans
- Thread starter maximus
- Start date
Ausbrooks
KNIFE MAKER
Maximus- you can get simple gas forge plans on the Zoeller Forge site, and there are others-Boss Dog has a good book on burners, which would be handy to have. I recommend you build a basic burner with a mig tip and iron fittings, which is easy and will help your grasp of the fuel/air process. I started out with a venturi burner and had trouble with it and went to mig tip atomospheric, then added a blower later, which don't really need staring out. The biggest thing I think is you pick a forge design that has burner mounted at an angle, and toward the back of the chamber, so it swirls the gas evenly throughout the space.
Wayne Bensinger
Well-Known Member
Max- I was in your shoes about a 1-1/2 yrs ago. I decided to do just what you are looking to do. First, I would think you would need to decide how big your average knives will be. Once that is done, I purchased enough 1-1/2 angle iron to build a frame, obviously you could bolt it together, but I think welding is easier and stronger. You will need fire bricks, not sure what is used in your gas forge, but if my memory serves me, you will need to get the very lightweight F-21(I think that's right, but do a search on Google for sure). A heating element is also needed, I would recommend a 240v because it just heats up so much quicker and it actually uses less power because the oven is not on for such a length of time. You can run it off a 12/2 household wire just like you would for a wash machine, one leg on the black, the other on the white. You need to also get a PID controller to program the oven, SSR(solid state relay), and a K-style Thermo-coupler to measure the temp inside. These three items can be bought online as a package but the directions are in half English, half-who-knows-what-language, you just need to decipher some of it. A limited knowledge of electric got me through with a few mistakes, but nothing major. LOL!
The frame and door are fairly easy as is the placement of the firebricks, keep in mind you need to slot the firebricks about the same size as the element diameter so you can set the element under the surface of the firebrick so it doesn't protrude into the oven space, very dangerous, 240v remember! When you receive your element, most likely you will get a few extra feet of the wire that you will need to make small staples. Don't skimp on this part, make all of the staples that you can with that wire and pin the element down every 2-3 inches into the fire brick. If you don't put enough staples in, the element will twist and expand out of the slot. Once it heats to high temp once or twice, it gets brittle, so you want to be careful about this step. The element will come short and tight, you will need to stretch it to the length you have made the trough with enough to get the leads out the back. The hard part is getting the leads on the ends of the element and the Thermo-coupler through the back wall and into the PID controller.
Then all that's left is to dress it up on the out side. I installed feet on mine that I can adjust it the table out of level, and 26 gauge sheet metal on the outside to protect the brick. Keep in touch if you have some more questions, which you may. Maybe you could private message me.
Wayne
The frame and door are fairly easy as is the placement of the firebricks, keep in mind you need to slot the firebricks about the same size as the element diameter so you can set the element under the surface of the firebrick so it doesn't protrude into the oven space, very dangerous, 240v remember! When you receive your element, most likely you will get a few extra feet of the wire that you will need to make small staples. Don't skimp on this part, make all of the staples that you can with that wire and pin the element down every 2-3 inches into the fire brick. If you don't put enough staples in, the element will twist and expand out of the slot. Once it heats to high temp once or twice, it gets brittle, so you want to be careful about this step. The element will come short and tight, you will need to stretch it to the length you have made the trough with enough to get the leads out the back. The hard part is getting the leads on the ends of the element and the Thermo-coupler through the back wall and into the PID controller.
Then all that's left is to dress it up on the out side. I installed feet on mine that I can adjust it the table out of level, and 26 gauge sheet metal on the outside to protect the brick. Keep in touch if you have some more questions, which you may. Maybe you could private message me.
Wayne
Wayne Bensinger
Well-Known Member
Hey Max, let me know and I can send some pics if you need.
Wayne
Wayne
Kayakersteve
Well-Known Member
Love to see you attach pics to thread - very interested
Yeah Wayne, pics would be great. Also where did you purchase your parts?(elements, controller etc). I don't think wiring will be a problem as I am somewhat proficient at it. I'm a union pipefitter specializing in refrigeration system installation so I have some training in wiring, troubleshooting etc. Thanks for your help. If you would rather use email I'm at kenmitzjr@gmail.com
HarveyBlades
Member
The videos by libris custom knives on youtube were very helpful when I built mine. There's a wiring diagram which is the only complicated bit. A router bit in a drill press is very handy to cut the channels for the elements
Lyon
Well-Known Member
I looked at the paragon ovens and copied the internal dimensions then bought the corresponding replacement element. The soft bricks also cut easy with a hand was. I cut 2 45 degree slots and then popped out the piece with a screwdriver. You can shape the cutout with the screwdriver and refine the edges really easy too.