Building a Powder Coating Oven

[woodstocka1]

I'm building a powder coating oven 80in long 40in high 30in wide and I have 18 ga sheet metal for the interior walls , mineral wool for insulation , metal studs for the frame . What would be best for the exterior walls ? I would like to hear from anybody that has built a P.C. oven and let me know what they used and how it turned out . Thanks :o:o

[doghows]

Both my ovens at the shop are sheet metal inside and outside. The wall thickness is 6". Just make sure you can reach at least 400 degrees or it will take you forever to cure your parts.
My small oven is 750,000 but and the big oven is 1.2 million btu, so make sure you have enough btu's as well. Good luck. [thumb]


Also be very careful what type of powder gun you use. The one you get from Eastwood, or harbour freight will get you mediocre results. You need to be able to adjust your voltage, micro amps, and your flow and cfm rates to get good results. My main gun puts out 60,000 volts and adjusts anywhere down to about 10k. If you are ever in the Sequim area I'd be glad to show you how it all works.

[woodstocka1]

Do you think I should stay with the 18ga on the outside or should I try for a thicker ga . The steel studs are 4in thick, will the mineral wool make up because I'm only 4in thick? I know you can't answer every thing but maybe you can give me a idea which way to go. I live in So California so I can't make it to your place but you have been a lot of help and I thank you for your help, if I can be of any help let me know .[thumb]

[doghows]

I would try and double up on the mineral wool. My big oven has two layers 4" thick. You should be fine on the metal gauge. Keep in mind the better the insulation the more efficient your oven will be. Also if possible make it convection. Even heat is crucial to curing the powder correctly, if you have hot spots you will over cure the powder in one spot and under cure it in another.
You need to obtain a substaight temperature of 375 degrees for 15 minute for most powders to cure properly. If you plan on doing any candy colors that's a whole other ball game. Keep us posted and I hope all goes well. :D

[woodstocka1]

I finished the three walls and I'm going to put the outer sheet on the door.The inside is 28in w x40in D x76in H, insulation is 4in all around ,It will have heating element on the bottom and on the back (lower bottom) what kind of amperage would I need to bring it to about 400degrees ? Any info. On sealing ,size /make of heating elements and what ever comes to mind will be appreciated . THANKS. OSCAR:doh::BEER:

[doghows]

Mine are all gas fired, electric takes way too long and costs way too much.
My small oven is 750,000 BTU, it is about double in size to yours. My large oven is 1.2 million BTU.
I would be no help when it comes to electric. It costs me about $40 to run the small oven for one batch, electric would have been at least double that cost.