I was given an Optoma HD700X projector for free, but it was broken. About every 15 pixels across, there was a vertical white line. I googled a bit and it seems that this happens fairly often on Optoma projectors (even shortly after they are bought). It found that it was likely the main board that was in need of repair.
I called Optoma, and they said the main board was $270. Since this was free, I didn’t want to pay to risk fixing it and have it not work, I’d rather put that much towards a new projector! I noticed that if I pressed on the top behind the focus ring some of the white lines would go away, leading me to think it was a poor solder connection. Since I already have a projector I thought I would try to fix this myself with a reflow.
Solder reflowing is simply heating the circuit board back up to the temperature it was at when it was created, so that the weakened solder joints liquefy and make contact again. The HD700X is a rebranded HD65, so I followed partial disassembly instructions from here. Then I put the board in a pie pan, then a turkey pan (to help dissipate the heat evenly), and put an inch of solder in with it instead of a pop-up timer, and put it in the oven.
Andy is totally just like Julia Child.
Then I set the oven for 550F (has to be above 270C) and waited.
After about 10 minutes, we noticed the solder had melted, the oven was at 465F and still heating up, so I turned it off and opened the door and we waited another 20min for it to cool.
Once it was cool I took it out, we reassembled the board, and it worked*! I was amazed it actually worked.
* Well it worked after I put it back together *correctly*, the power cable from underneath was backwards!