CertainTeed Machine Works has introduced the Glass Master SG-420 Duct Board Grooving Machine – a powerful machine that fabricates high-quality fiberglass spiral ducts more accurately, and up to 50 ...

Precision-ground and hardened tool blades generate clean grooves and consistent contours and duct dimensions. It can be easily adapted to groove 1-, 1½-, and 2-inch boards. Its square duct tool ...