You should just make a very small hole, and then after you fire it, grind it out CAREFULLY with a roto-zip bit made for glass, and use a rubber grommet for the final fitting. I'll post 'in progress' pics next time I make a glass piece.
stinkyattic Reviewed by stinkyattic on . Clay Bongs, bowls, chilliums, pipes.... Does anyone here know some good teqnuiqes or tips for clay bong and peice making? One particular problem of mine is I cant think of a good way to make the slide fit just right so that its air tight... :o Rating: 5