Shop Dust Collection: Straight Ducts and a Switch-Operated Blast Gate

A table saw that had sat open for ten years was the reason the rest of Adam Savage's dust collection system pulled so weakly. The saw had no gate on its dust port, so its line was always open and stole suction from everything else. Fixing that was the core of a one-day build in his workshop, which he calls the cave, where he replaced ribbed hose with straight tubing, added a longer leg to the far end of the shop, and put in an electromechanical blast gate on the saw.

Why the old hose had to go

The starting point was a dusty Christmas. Building end tables filled the shop with dust, and Savage realized the ribbed hoses running up to the Delta dust retriever in his loft were not good enough. He called his friend Kip, who told him the ribs cause turbulence, which effectively makes the tubing smaller and reduces suction.

The plan had three parts: swap most of the ribbed hose for straight tubes, add a longer leg to reach the other end of the shop, and drop pickups from the system so he could plug them into cordless power tools. He had found that an orbital sander was a spectacular way to add dust to a shop.

Building the duct network

Savage cut the straight clear tubing to length, made connector pieces to join four-foot sections, and cut extra pieces for the upright. He assembled as much as possible on the ground so there was less to do while working up in the air. Twist caps held the sections together; he reported that the yellow ones are better than the green ones, which are a little tougher to make work. The result was nearly rigid, which he wanted because a rigid run has the fewest bumps in the line.

He did not eliminate all the ribbed hose. He kept some flexible hose where he needed to make certain turns, including the connector to the dust retriever in the loft. Plywood clamps he had made held the pipe to the wall and into the beam behind, and zip ties secured other runs. At the back of the retriever he fitted a splitter, with one branch going down to the table saw and the other across the shop. He also built a vacuum hose with an outlet for sweeping up.

A first test with the splitter capped gave good suction, and the vacuum hose picked up well, though not as vigorously as his shop vac. He ran short of clamps and taped one section together to fix later. After seeing the system work, he said he may upgrade to a larger-horsepower dust retriever.

The open table saw problem

The line to the disc sander already had a manual blast gate he made years ago. He just reaches down and opens it, which is fine because he is the only one in the shop. The table saw was different: with no gate, its port stayed open and weakened suction everywhere else, and he did not want to reach behind the saw each time.

His answer was an electromechanical blast gate, which he said costs over 100 dollars on Amazon. He noticed it had a 1/8 in. stereo mini jack, and plugging one in opened the gate. He joked that the gate could cut his fingers off and said he would keep them out of the way.

Mounting the gate and wiring the switch

Savage mounted the gate to the saw with 3 in. 1/4-20 bolts and nuts, using the nuts to space the gate properly. Since he only needed one of the gate's inputs, he used a momentary push-button switch. He made a 12-foot lead from solid core speaker wire, added three layers of heat shrink for strain relief, and held the cable with wire carriers and self-tapping sheet metal screws. The metal needed pre-drilling, and he used cutting fluid when drilling the hole for the switch.

With the gate closed, the drop line gave a significant amount of suction. Comparing the two states with the gate open and closed, he found the open gate gave about half the suction.

Results

He tested the disc sander with 40 grit and took off a lot of material with no dust at all. A control run without collection made him sneeze, and then the second pickup point worked as well. By the end, the table saw, disc sander and small handheld sanders all had dust collection. Savage said he is still wearing a dust mask more often since viewers urged it after the end-table project. His next idea is a small movable airbrush vent.