Hi flyfast,

To add to the excellent advice to date I have found that if you join the two pieces as described it only works for me if the join is in a straight line over open frame work, Im probably doing it incorrectly. If the line is curved I have only had success if there is sheeting under the join. My two cents worth, and that is probably more than it is worth is to add some thin sheeting under the line of the join.

Good Luck,

Colin