Build a Motor Cover for a Vintage Unisaw
Measured cut list and how-to instructions for building a plywood motor cover for an older Delta Rockwell Unisaw. The cover encloses the motor for improved dust control. Project requires one 2' x 4' piece of 1/2" plywood, a 18" piano hinge, basic shop tools, and a few supplies from the home center. Total cost is ~$50.00 if you have to buy everything. Alternatively, you can purchase aftermarket motor covers for Unisaws that are made of black plastic for about $100 online or hunt down a used part on Ebay for about $200.
Check your saw's opening; it may be different than mine. The motor opening on my saw' stamped-steel base is 15-1/8" wide by 16-3/4" tall with radiused corners. There are also 4 holes near the corners, but my motor cover design does not utilize them. My saw is a Rockwell #34-461 built in the Tupelo, MS factory in 1975. The metal at the lip is rounded over, so go a little wider when designing your box for complete coverage - something like 15-5/8" for the minimum width gives me enough room to attach the hinge screws to the base.
Materials Needed
**Not all Unisaws are the same. Double check the distance your motor projects from the saw cabinet. The 5-3/4" depth of the motor housing box I show here might be too small on some newer saws. Adjust as needed.**
Plywood - 1/2" Sandply (2 ft x 4 ft piece).
Brad Nails - Use either a 18g pneumatic nailer w/ 1-1/4" brads or a hammer w/ ~1" finish head wire nails.
Machine Screws - Use hinge screws or upgrade them.
Glue - Titebond II.
Foam Weather Strip - 1/4" medium gap for windows.
Piano Hinge - ~18" long (or cut down a longer one).
Latch - Find a clasp or magnet that works for you.
Wood Filler - Rock Hard or any other wood putty.
Paint - Rustoleum Gloss Enamel "Charcoal Gray"
Cut Out Parts from Plywood Sheet
The "hinge side" is marked on the wrong side in the diagram. It should be on the right side of the box as it sits on the saw. Box should latch near the right front corner of the saw; the hinge near the back right corner.
Step-by-Step
0.) Measure your saw's motor opening. Alter the plan if your opening is a different than mine.
1.) Cut out parts as per cut list diagram above.
2.) Assemble plywood parts with glue and brads. Corner-squaring braces help.
3.) Use a block plane to bevel the edges on the Front and Angle parts as shown.
4.) Set nail heads below surface, fill nail holes with putty, and sand entire box smooth w/ 150g.
5.) Spray with several coats of paint and let each coat dry. Sand lightly between coats w/ 320g.
6.) Install one side of the piano hinge on the 1/2"-wide plywood edge. Add a hardwood strip if needed.
7.) Mark out and drill holes for the other side of the hinge on table saw base. Find a helper for this.
8.) Test fit cover on saw base. Complete the rest of the hole drilling if things look good.
9.) Install hinge to saw base; use either the screws that came with the hinge or upgrade the screws.
10.) Install foam weather stripping.
11.) Install latch.
Don't be like me. Cut your "angle" piece an inch longer, then trim and bevel it back to create a clean joint. I forgot to do it on this prototype. The long gap doesn't go all the way through, but it is unsightly. I haven't filled the nail holes here, either. Do yours right.
You can add a ramp inside to better move dust downward, but that would be more work. And no one wants that.
Off the shelf latch and a 1" riser block screwed to motor cover box. Will be painted.
Test fitting the new cover to the cabinet. I will add a vertical wood strip to the front edge of the box, below the latch. That way I can rework the foam seal so it looks cleaner.
More to come...
