UP HOMEClick on any photo to see a larger version
I was given a flammable material storage cabinet a few weeks ago and it screamed "Make me into a huge powder coating oven". I acquiesced to the little voice...
The cabinet has double walls (a little over an inch) and is sturdily constructed. The most vexing part of the conversion was insulating the cabinet. I elected to fill the hollow walls and ceiling of the cabinet with Perlite.
I used three 2000 Watt oven elements for heating, driven by three 40A SSR's and controlled by a MYPIN TA4 controller. The 40A relays were a bit of overkill, but with china made SSR's better safe than sorry. Current draw for all three elements going full bore is 32 amps. From ambient to 300º is about 15-20 minutes. With the insulation installed most of the cabinet is warm to the touch. There are a few spots, most notably along the division of the doors and the top 2" of the sides where the temps are high enough you can't keep your hand on the metal for long, if at all. I am planning on adding some sort of sealing strip between the doors.
Parts listing here
Pouring the Perlite into the ceiling cavity
Tipping the unit back upright