I've been looking to test a homemade rocket I made with a sugar motor. Problem is I've always used commercially bought motor casings which is shared among a group of us. I've used PVC/ABS as motor casings before for smaller rockets but now I'm looking at 38 and 55mm engines. My worry (without testing) is that it will melt the nozzle, and possibly ruining my rocket. I'll be testing this weekend to see if I can use PVC or not but I was wondering if anyone else had experience with custom motor casings on a budget? Maybe some kind of high heat coating the inside of the PVC or just order a custom aluminum casing with threading?