In a message dated 5/23/00 1:43:04 PM Central Daylight Time, tesla-at-pupman-dot-com writes: << Original Poster: Esondrmn-at-aol-dot-com Hi Ed, The advantage of using the pipe connectors instead of the rigid pipe or the tubing is that you won't have to mess around with the deburring. I probably do not understand your construction description, but how are you going to draw air into the "airtight box?" Happy day, Ralph Zekelman