I've always used simple green or iso to clean my pieces, but on a piece I have resin built up just above the water level and I can't get it to budge, so my question is: Do I just submerge the piece in the boiling water? After taking the ds and bowl out of course.
Use alot of salt with your ISO or alcohols. It helps scratch away at the chunks. I myself have not boiled glass to clean it but I have heard the method. From my understanding. Do it at your own risk, heating cheap/thin glass can easily crack under temperature change. I would also submerge your bong in lightly warm water(in the pot) and then boil. Do Not Stick Your Bong Directly Into Boiling Water! Also do not cool down the glass to fast. I'd just stick to alcohol and salt IMHO.
one method i did that worked really well was going back and fourth, two bottles, one with heavy salt water, the other with iso 90% first the salt, half the bottle poured, a good swivel for a few min, pour out some iso, soak and swivel mix, later on, pour out back to salt iso one more time, this time leave to soak then pour out salt last time to get it all out and done very very very good rinse seems like a lengthy process, but its really not, a few min here a few min there throughout a day and BOOM, a bong that looks brand spanking new of course i have only had to do that when my bong gets real nasty i usually keep it pretty clean so ive never had to go all out