Today, I had a pipe maker tell me that he tried to make a sandblast finish pipe with a smooth rim, but that it didn't turn out so he sandblasted the rim instead. I don't know a lot about making pipes, but does this make any sense? It seems to me like having a smooth rim would be simple- even if you jacked the rim up while sandblasting the bowl, you could just sand the rim smooth again. Is it more complicated then that?