Silicone sealent on a bong?

[TheGanjaKing420]

Yes, I use it all the time on my homemade bongs. To this day I haven't found a better substance that does the job.

And as for brass pipes, I've been smoking out of those for years, and never heard they are bad. Copper is bad and I always stay away from that. However I used to smoke out of beer cans all the time. No problems with me that I'm aware of.

[Daveracer]

You could buy orange RTV from an automotive store. RTV orange is high temperature sealant, and i think it's good for over 800-1000 degrees. I use it for exhaust gaskets when i'm in a bind.