Mother's Woodshop: Dust Buster

by Bill Greene

While it may not be economically feasible to install a sawdust-control system for the entire garage, we can assemble a self-contained sawdust evacuator for one of the greatest contributors of sawdust in the shop: the table saw. And while prices will vary at lumberyards around the country, $60 should be enough for the wood, hardware, glue and paint needed for this project, give or take a few bucks. Throw in a five-gallon, 1.5-horsepower Shop Vac® for around $40, and a dust-free garage is easily worth the price.

MATERIALS LIST

LUMBER
(5) 8'-long Douglas fir 2x4 studs
(1) 5' length of 1"x6" pine (finished 3/4 x 5 1/2")
(1) 30"x 25" piece of 1"-thick marine-grade plywood
(1) 11"x 10 3/4" piece of 1"-thick marine-grade plywood

HARDWARE
Cap screws: (8) 1/4" x 4 1/4" each with a wing nut and 2 flat washers
Carriage bolts: (8) 3/8" x 3 1/2" each with a wing nut and 2 flat washers; (4) 1/4" x 2" each with a wing nut and 2 flat washers; (4) 1/4" x 1 1/4" each with a wing nut and 2 flat washers
Lag screws: (8) 3/8" x 1 1/2; (8) 3/16" x 3 1/2"
Flat-headed wood screws: (16) #5 x 1 1/2"; (8) # 8x3"
Nails: (16) 2d, 3" box nails; (8) 8d, 3" box nails; (24) 2d, 1 1/2" finishing nails

GLUE
(1) 7 5/8 oz. bottle of Elmer's Carpenter's Glue or equivalent
(1) set of epoxy cement (preferably 2-ton strength)

PAINT
(1) pint of gloss enamel
(1) quart of latex flat paint

SHIMSTOCK (OR COPPER TUBING)
24 sq. inches (or 2' of tubing)
*Note: Copper tubing can only be substituted if available in suitable sizes.

Our table saw is located in an end-of-the-garage workshop where space is very limited (it's no more than 5' x 12'). After acquiring a basic no-frills table saw, I decided I needed a saw table that would meet several requirements. First, it had to be comfortable for my 6' 4" height. I also wanted it to be easy to move and fairly easy to dismantle for convenient storage. Most importantly, however, the table had to have a built-in sawdust evacuation Sys tem because the people in my household are allergic to sawdust. In the end I was unable to find a commercially made saw table that met all of these requirements, so I decided to build my own.

The Table Top and Base

The saw table is 34 1/2" tall. It has outslanting legs with skids connecting each pair on their lower ends. The table surface measures 25" x 30" with an 11"-square drop hole cut in its center. The sawdust evacuation system consists of a boxlike sawdust collector attached to the underside of the table directly under the drop hole, with its outlet spout connected to a 2-horsepower shop vacuum cleaner that draws the sawdust out of it.

Both the saw table and sawdust collector are constructed mostly of wood, and the whole structure is mounted on skids to make it movable yet still stable. The legs, braces, sawdust collector and saw are also detachable for easy storage.

After you cut the 25" x 30" saw table top from a 1"-thick sheet of marine grade plywood, round its corners and cut an 11"-square drop hole in its center, you'll want to build a base for it. This base acts as additional support and pro vides sturdy mountings for the legs.

The front and rear faces of the base run almost the length of the table at 24 1/4" long - the last 5" on both ends of these faces should be strengthened (or widened) by adding 2" x 5" pieces of Douglas fir and expanding the width of the ends to 5 1/2". Reinforce by backing each of them with pieces of 1 "-thick pine measuring 5" x 5 1/2". These expanded and reinforced ends can be assembled using 1 1/2" long #5, flat-headed wood screws and 3"-long, 2d box nails.

Angle the entire length of the base by sawing out a 1/2"-wide triangular section so that when installed under the tabletop it will give an outward slope of about 15°. This gives the legs a wider stance once they're attached, and makes the table more stable when you're feeding material backward and forward through the saw. Secure these canted faces to the underside of the table with 12 3"-long, #8, flat-headed wood screws (six per face) and carpenter's glue.

Cut the two sides of the base to 21 3/4" lengths from 2x4 Douglas fir stud stock and attach to the underside of the 25" width of the table top at a 90° angle using 3"-long, #8, flat-headed wood screws (four per side) and carpenter's glue. Also, attach the sides to the front and rear faces of the base with 3"-long, 3/16" lag screws (two for each end).

Legs, Braces and Skids

The leg, brace and skid assembly consists of four legs (each 33 1/2" long), four braces (one for each side, front and rear) and two skids. The front and rear braces are both 24 1/2" long and are permanently attached to the legs with 2 1/2" - long 3/8" lag screws (four per brace), resulting in two pairs of legs and braces. As for the skids, they measure 32 1/2" long and are attached to the bottom ends of each pair of front and rear legs using 3"long, 8d finishing nails.

Join the legs and side braces with carriage bolts, wing nuts and cap screws so they can be easily dismantled without using a wrench. Attach the legs to their mounting points on the saw table base with removable 4"-long, 1/4" cap screws, wing nuts and flat washers (four per pair of legs). All of the cap screws should be 3/8" in diameter with sleeves. Then angle the ends of the side braces to match the Outward slant of the legs (lengths on the top and bottom surfaces should be 25 3/'4" and 27 1/2", respectively) and attach the side braces to the legs on bolts projecting from the brace supports.

To permanently mount the brace supports on the backs of the legs (one per leg), use two 3 1/'2"-long, 3/16" diameter lag screws for each support. If you cut the braces at an angle to match the outward slope of the legs, their upper and lower edge lengths should be 3" and 4 1/2", respectively. Fit the. supports with two 3 1/2"-long, 3/8"-diameter carriage bolts inserted from behind through holes and sealed with epoxy cement. Mount the side braces by sliding them into place through their 7/16"-diameter, sleeve-lined mounting holes and hold in place with wing nuts and flat washers. The sleeves used to line the mounting holes come from brass shim stock. Simply shape the brass around the appropriate diameter bolts (either 3/16" or 3/8" diameter) and secure their respective holes with epoxy cement. Substitute copper tubing if needed.

The Funnel Dust Collector

With the exception of its outlet spout, the sawdust collector is entirely constructed of wood and shaped to funnel sawdust down into the Shop Vac® beneath the table. The entire unit consists of five pieces and two cleats. Join the four sides - cut from 1/2" plywood - with 2d finishing nails and carpenter's glue and secure parts labeled Al and A2 inside of B1 and B2. Pieces A1 and A2 should measure 8 3/8" long and angle (at 45°) from a 12 1/2" width at one end to a 1 1/8" width on the other. BI and B2 should measure 8/16" long and angle (at 45°) from a 12 1/2" width to 2 1/2° (see illustration). Attach the cleats - cut from 1x6 pine stock - to the upper outside of B1 and B2. To accommodate your Shop Vac® hose fitting, bore an appropriately sized hole in a 1" plywood plug measuring 2 1/2" square. Be sure to attach the plug to the construction and let the glue dry before boring your hole.

The next step - finding a tube that has a 1 1/8" outside diameter (the size required for a spout that would fit snugly inside the intake hose on a Shop Vac®)proved to be a challenge when I was building my own sawdust collector. I ended up using two old medical prescription containers that could be made into tubes by cutting the ends off. One had an outside diameter of exactly 1 1/8", and the other one fit tightly inside the first. After epoxying the two together I finished with a very strong spout. If you don't do it this way, make sure to leave 1 1/2" of the tube projecting outside.

When you're finished, attach the sawdust collector to the underside of the saw table with 2"-long, 1/2"-diameter carriage bolts that are epoxied in place to the saw table (this is the same technique used in setting carriage bolts in the side brace supports on the table). Attach the carriage bolts to the sawdust collector by thrusting their ends through the holes in the collector's 1" lip that is formed by the 1x6 pine cleats. The sawdust collector should be positioned directly under the drop hole in the tabletop.

I have used this saw table with its sawdust evacuation system for a little over a year and found it to be quite satisfactory for my purposes. After some research (weighing sawdust collected in the Shop Vac® and swept up from the floor outside the system), I concluded that it removed between 75% and 85% of the sawdust generated by the saw.

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