Oven Sizine

[GAWnCA]

I have a quick question, I'm going to be doing powder coating/ceramic coating from home. I need to know what would be the best size for an oven. The largest thing I'll be coating is a set of over the transom headers, that measure roughly 52" by 14" each. I would like to be able to do a pair at a time.



This is just a sample photo of what I'm talking about. As you can see, this is really the largest items I'd need to accommodate at this time.

[ed_denu]

Whatever size you build you will eventually run into a part that won't fit. You need to determine what size would fit most of your needs, it could be 3X3X5, 4X4X6, etc.

But before you make that decision, insure that you have the necessary electrical power to heat the oven. If you can determine the maximum amperes you can dedicate to an oven, that will set your high end size limitation.

As an example, a 4X4X6 oven will need around a 70 amp circuit to heat properly. A 3X3X5 will require 40-50A. It can get rather expensive to add a new subpanel to a garage or workshop.

[GAWnCA]

Thanks Ed, I can handle another double 50 amp breaker for this project. I'm just limited on room for the oven. How high above the elements should you stay? For the time being, the headers will be the bigest item I'll try to do. Anything bigger and they will have to go somewhere else.

[ed_denu]

If your concern is radiant heat, then you can incorporate element shields into the design, just don't totally block the elements or the oven may overheat. Recirculating fans also help greatly to even out temperatures throughout the oven. It's probably most common to place the elements on the oven sides. Sometimes they are mounted on the floor, but imo this makes loading and unloading the oven more difficult.

Your 50 amp capability will limit you to around 40 amps or 9500 watts(80% continuous load). Since you're doing headers you will probably be looking at ceramics that need 550 degrees. I would stick to the 3X3X5(45 cu ft) size, as doubling the size to 4X4X6(96 cu ft) would not get to temperature imo.

[GAWnCA]

Thanks again Ed. I'll try the 3 x 3 x 5 and see how that works out. I'll also put a fan in for circulation.