Save time, money, and hassle using shop-made, multiple-tool blast gates
Because I work alone in my shop, and never need dust collection at more than one machine at a time, I developed a single blast gate that controls airflow to two machines. (My two-gate system is shown; I have a similar three-gate setup, too.)
It's made almost entirely of 1⁄2 " plywood except for the slightly thicker hardwood strips that enable the nozzle plate to slide. Slide the plate to align either nozzle with the dust-collection hole in the baffle plate; the middle position blocks airflow altogether. Index marks show you when the holes, as well as the blocked position, align so that you can release the latch, catching the tip of its bolt in a hole in the baffle plate. You'll likely have to do some fine-tuning to the hole and nut diameters, as well as the spring strength, to ensure the latch works smoothly.
—Peter Huckstep, Albion, N.Y.