Re: SG poor sustain
Hi, if you have a "Nashville" bridge-this might help.
Look up ABR vs. Nashville bridge, many here swear by them.
My SG '61 R.I. seemed on the thin side at first. So I looked at the bridge. It came with that crappy "sleeve" style flywheel, so I disasemmbled it and the sleeve itself (the part that is inside the body) was covered in paint and I could make it wiggle with my hand. So I took it out, cleaned the paint off the metal, crushed some maple pieces and put them in the now open wood hole.
Then I needed a slight tap with a hammer to get the sleeves back in (this good for vibration transfer) thus making it tighter. Mine came w/a Nashville type bridge instead of an "ABR" which is original stock and much denser all around. I then had to file the flyweel top post a little so it would accept my ABR bridge. The ABR is not as deep so I only had 1 string that was hitting. Most folks would not do this, but I just simply got my small round rat tail file and gently made a groove so the string hit the saddle only.
My stopbar is screwed down hard! It also had paint covering where the bar screws(the big ones)screw into the big stop bar sleeves, so I cleaned those also. Now I have ultimate contact, I use a much lighter string, a D'Adarrio 9.5, 11.5, 16' 24, 36, 46. They work well for me through a 15 watt Blues Jr. and on stage a 40 watt Fender Hot Rod Deluxe. Kicks rear end either way. I use a Seth Lover also, but on MJ's advice (again, most folks don't care for this) I put an A5 magnet in it so it is louder, tighter on the low end, but does add extra high end. My choice. But the original A2 Seth sustained great after I fixed the bridge set up.
Good luck,
Steve Buffington EDIT: What everyone else said also!