This is probably obvious, but I'll mention it here for future readers of this thread: once it's been used for reflow work, the oven should never be used for preparing food again. And preferably not before, either, if you can find an unused one - I don't know what the effects of vaporized bacon grease are on a PCB, but it's probably best not to find out, eh? xx(
The idea being that the board is ready at just under the reflow temperature, and the heatgun takes it up and over, right?
Pros also use a temp-controlled flat hotplate to get a board warmed up. I picked up a nice pancake maker with a flat (not curved) teflon surface, which with a bit of hacking should do the trick for that too. Amazing what you can find in the kitchen aisle }
Wow, 475C (887F)? That's some crazy heat alright. 8-o How long did you leave it in there?