I am going to build one anyway, because I cannot find an oven that is set up the way I want it.
The oven will have two banks of heating elements. I can switch to the upper bank and raise the internal platform, which will give me a smaller oven, or remove the platform and use the lower bank of elements to heat the larger volume.
The walls, door and ceiling will all be 6" steel studs with rock wool insulation. It will sit on the concrete floor. I am not planning to have an insulated floor, UNLESS it is particularly beneficial.
I have the design made, with two banks of burners and a center platform that will allow me to slip it onto a support along the walls and reduce the size of the oven for smaller parts.
Everything is looking good, but now I am pricing STEEL.
Holy friggin' COW! I was going to wrap this in 20 gauge stainless inside and out. The best price I can find is $362.00 per 4x8 sheet.
At 12 sheets, that is a $4,000.00 "pretty" that I just cannot justify.
I HAVE a pallet of 16 gauge cold roll steel 4x10 sheets. I suppose I could use those. I rarely make anything out of 16 gauge steel.
So I got to calling around. I now understand why everyone's powder coat ovens are rusty inside. It costs to damned much money to give the interior any kind of finish!
I have a friend who has an HVAC business. He says he can get me 4x8 sheets of galvanized steel for $46.00 per sheet. The PRICE is awesome, but the $64,000.00 question is ...
Is it SAFE to use galvanized steel in a powder coat oven heated by electric elements?
He thinks it might melt at 400 degrees.
I will spend a couple of weeks building the frame, and the controller, and installing the elements, lights, fans, ducting, and so forth. THEN I have to figure out the skin.
Tell me this ... Is there any problem with using FIRE RATED 5/8" DRYWALL instead of steel for the skin inside? Does it HAVE TO BE metal? Wouldn't a double layer of 5/8" drywall work?
My other thought was, since the insulation is doing the job of containing the heat, can I use expanded metal inside? It would protect the insulation, but it is not a SOLID skin. It would give me a great option to insert rods across the openings to hang parts though.
I even thought about using tempered GLASS. Believe it or not, you can get large sheets of tempered glass for FREE! I did this in COMMIEfornia, taking the thick tempered glass panels out of sliding glass door frames to make solar heater covers. The glass shops GIVE them away, as people replace the older sliding glass doors with the new double panel gas filled vinyl framed stuff. Then they don't have to smash the glass into bins, and deal with all of that. As a bonus, I got to recycle the old aluminum frames!
The drawback of glass is that you have to work with the dimensions of the glass panels, as tempered glass cannot be cut. Also, you cannot drill through it to mount brackets or whatever.
Aluminum is out of the question, and I am assuming that aluminum would be self-defeating, as it would PASS the heat through to the insulation, right?
I am beginning to think I should call a tile man and have the whole thing done in ceramic tile!
Hey, it works on the Space Shuttle!Crazy times ....
Joe
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