im assumuur talkin about makin a getto bong or some thin but the best thing 2 doo ifur goin 2 make somethin is2 use a metal net the type people some times use over fish bouls and cages an shit aluminum foil will give u alstimers diesses i odont no about the cap thing sorry if u dont understand me i jus got home an im 7 beers deepp wit 3 shot of goldslaugger an i no most off the stuf i right is wrong