[Ackattack]

I initially heat my oven up to 500. It takes about 15 min to get it there. Meanwhile I "spray" the powder. Once it's up to 500, I throw the part in, close the door and immediatly turn it down to 450....it looses 50 degrees in those ~15 seconds it takes to put the part in there. Then I bake at 450 for 5 min. to let the powder "flow" out. Then I open the door again, and turn the temp down to 400 for another 20 min.

The reason I like to have air available while using the oven is I also use high pressure air to clean up the gun once I'm done using it. So, no, you don't have to have a big supply of air, but it's nice. Sounds like it will be a big pain for you to get air though.