bare metal and then the rubber rim tape(which also has a hole in it) the hole in the tube looks like... well like a cats bum hole :) or star ;)
Yes I had this very problem when I tried run my wheel without rim tape, its tube going thought the holes! but this shouldn't happen if you've got rim tape, try replacing the tape with some cloth stuff?
Yes I had this very problem when I tried run my wheel without rim tape, its tube going thought the holes! but this shouldn't happen if you've got rim tape, try replacing the tape with some cloth stuff?