I had to buy an angled ceiling mount for my pj, the Marantz S2. Because I had to mount to an angled ceiling, my pipe coming down from the mount is a little longer than usual, about 3' 8". For this pipe I bought a piece of galvanized pipe that is very heavy and probably adds another 15 lbs to the overall weight. I'd like to reduce the weight of this pipe by either drilling or blasting through some holes, still leaving plenty to be structurally sound. My wife thinks if I want to reduce the weight, I should just get an aluminum pipe (is there such thing as 1.5" aluminum pipe?) I have a 30 lb. projector to support. What should I do? Also, what length lag bolts should I go with to mount the ceiling plate to the ceiling joist?