Dynamo Men Lamp

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This article is from Issue 74 of Woodcraft Magazine.

Make this dynamic duo work for you

Who wouldn’t want officemates like these guys? Without complaint, or even a coffee break, this crew of two works tirelessly to help keep the light on. In truth, we know that lamps require electricity (just as coworkers require coffee), but this project is still an amusing addition to your workplace. The motor and lamp have their own switches so that when you’re not in the mood for perpetual labor, you still have a nice little table lamp.

Despite it’s complexity, this project isn’t difficult, even if you aren’t a super scroll sawyer. As you’ll see, my saw-and-sand technique creates smooth-running gears without the risk of stripping yours.

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Go to woodcraftmagazine.com to see a short video of these men at work. You’ll also find full-sized patterns for the gears, men, faceplate, motherboard, and back.

Minor motor modifications. To extend the motor’s driveshaft, I attached a 3⁄16" aluminum tube. To join the parts, drill a 3⁄64" hole, insert a brass escutcheon pin, and then “weld” the joint with a drop of superglue.




A motor moves gears & guys 

This project becomes less daunting when you realize that it’s just a basic lamp augmented by a motor that spins a large center gear. Smaller gears are connected to the large gear. Movement is transmitted to the figures through eccentric pivot points.

The gears are drilled, sawn, and sanded to shape. (I used Baltic birch plywood for stability and durability.)

Construction sequence

  • Build the case and base.
  • Make, test & install the gears.
  • Saw, assemble, and install the workers.
  • Wire it up.
  • Light it up.

Getting in gear

While some woodworkers rely on indexing jigs to make gears, I prefer to use full-sized patterns that provide center points for holes and sharp lines I can sand to on a small belt sander.

First, affix the patterns to plywood with Elmer’s washable school glue, taking care to press all patterns flat. Drill the holes as shown, then cut each gear free on the scrollsaw, taking care to stay outside your lines. Next, use a strip sander (with the platen removed for better maneuverability) to sand the inner edges of the gears. Finish up by sweep-sanding the outer tips of each gear.

Test the gears, as shown on page 25. If necessary, do more sanding until your transmission turns smoothly. Then remove the pattern with a damp sponge, apply a finish and install the gear assembly. To make the gears appear metallic, I painted them with copper and silver acrylic paints.
Bet on your brad point. Instead of marking center points with an awl, save time by pressing the brad point’s tip into your workpiece before turning on your drill. To prevent blow-out, place the gear on a fresh backer.
Sand to the line. After sawing out the bulk of the waste, I rely on my 1" belt sander outfitted with a 220-grit belt. Sand between teeth first (photo above), then remove the waste from each tip.
Take rough-sawn spacers for a spin. After drilling and rough-sawing the spacers, sandwich them on a 3⁄16" bolt and spin-sand on the drill press until they are perfectly round.
Use a bit of assistance. Because the gears and their respective spacers need to be perfectly concentric, I use the drill bit as an alignment pin when gluing these parts together.

Make & install the workers

If you’ve created the gears for a smooth-running transmission (facing page), you’ll have no trouble with these workers. As with the gears, drill the alignment and pivot holes first, saw close to the lines, then sand to final shape.

After assembling the workers, screw them to their gears and glue them to the base as shown in the photos below.

Connect the motor and lamp socket wires to the lamp cord, using the wiring diagram below. Attach the back when you confirm that everything works. I tacked the lamp cord to the base with a dollop of hot glue to keep it from pulling loose.
Let’s get cranking. I cut threads in the gears to hold pivot screws, but a dab of epoxy will also do the trick.
Take a stand. I center each worker about 5⁄8" in from the sides and 1⁄16" back from the platform’s front edge. The alignment toothpicks make handy reference points.

Patterns for guys & gears

Make time for a test spin

Even though I’ve made wooden gears for years, I still try them out on a test board before assembly. Use the gear pattern to locate the holes on the faceplate.

Need Parts?

A printed set of patterns—and all components excluding the flat stock, paint, and bulb—are available as a kit. See the Buyer’s Guide on p. 66.

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