The drawing shows my solution to the perennial problem of capping a partially used tube of caulk. The cap is made from an empty 35mm film canister that has been filled with petroleum jelly. A 5/16-in. dia. hole in the bottom of the canister allows the tube’s nozzle to be inserted into the canister for storage. The petroleum jelly makes an airproof seal around the tube tip, preventing the premature curing of the caulk.
Phil Keller, Burnt Hills, NY