Designing an efficient ductwork layout is an important part of setting up any shop. Check out this list of the DOs and DON'Ts of ductwork to get the most out of your dust collection system.
DO keep elbows and turns to a minimum.
The fewer the turns the better and the shorter the degree angle of turn the better.
DON'T use long ducting runs.
Ducting causes friction or drag which reduces fan performance. Shorter, more direct pipe runs are best and will deliver more air volume to woodworking machine.
DO use blast gates at every machine to control air flow.
The locking screw-pin should be tightened in the direction of the airflow, with the head of the screw facing toward the woodworking machine.
DON'T use 90 degree tee branches.
Use 45 degree wye branches instead. High-pressure systems such as the Supercell are the exception to this rule, where any pressure loss from a tee will have a negligible impact on the overall performance of the system.
DO use the proper gauge pipe.
Thinner gauges (such as HVAC pipe) can collapse under fan pressure or dent easily. Small custom shops do well with 26 - 22 gauge pipe and fittings. Big molders or machines that generate huge quantities of solid material generally need 22 - 18 gauge pipe and fittings for industrial survivability and safety.
DON'T use PVC piping.
Scientists, engineers, and industry experts who work in insurance, human safety, woodworking, and equipment manufacturing consistently agree that plastic pipe should not be used in material (wood waste) conveying. The National Fire Protection Association’s 2002 edition, Chap.8 / 8.2.2.2.1.2 states about wood waste conveyance, “Nonconductive ducts such as PVC pipes shall not be permitted.”
