How do I cut a spin-in collar into a piece of round spiral duct?
2nd YearFlex Duct & GrillesYELLOW · Check First
1. Place the spin-in collar flat against the spiral pipe and trace around the inside diameter with a marker. 2. Drill a pilot starter hole inside your marked line. 3. Use a pair of red or green aviation snips to cut out the circle cleanly, staying exactly on the line. 4. Insert the spin-in collar flange into the hole, press it firmly down until the mechanical tabs lock, and secure the perimeter flange using short tek screws before sealing with mastic.