Attributes . Cut tubing squarely- maximum of 15? angle allowable. Check that port or mating part is clean and free of debris. Insert tubing into fittings until it bottoms on seat. Tighten nut with wrench until one thread remains visible on the fittings body; (this will allow for a number of remakes) or, the nut should be screwed down finger tight, then wrench-tightened according to the tube size used. . Names