Building a powdercoating oven big enough to fit a frame isn't hard but by the time you get it built the cost wouldn't be worth it unless you were doing multiple parts. Here is what a friend did to build his own.
4x8 sheets of steel 7 of them: approx $200 per sheet
High Temp insulation: approx $636
2 used oven heating elements: about $25 (junk yard)
Total Cost was $2500
Most homes have a 200 amp service so he was able to do this. His oven was 8' tall x 4' deep x 8' wide. He had scrape steel angle that he used to build a frame to weld the steel sheets too and to hang parts from. Mounted one oven heating element on the back wall about halfway up the other was mounted down near the floor. Both elements had their own controls. He mounted a heating sensor near the floor to see and help control the temp in the oven. He could get the oven to about 575 degrees with out any problems. The electric company really like him too!!!
Now you may ask why would someone go through all this trouble to build one. He loved street rods and had 6 at one time he was making. Powdercoated everything he could on them. Had more money and time the anyone should. But most of all he just wanted to say he had built one. He had it for about 5 years and then passed away. His wife sold everything and moved to Florida.
