PROJECTS: MOST USELESS MACHINE
3. BUILD THE CIRCUIT
3a. Now it’s time to fire up the soldering iron. If your motor
already has leads attached, solder them to each of the 2 middle
legs of the toggle switch. Otherwise, cut, strip, and solder wire
leads between each motor terminal and the middle toggle pins;
4" long is plenty for all connections in this circuit, and you may
want to shorten them later for neatness.
3b. Solder a short jumper wire diagonally between 2 opposite
corner legs of the toggle switch, then solder separate leads to
the remaining 2 legs at the other corners.
3c. Solder the 2 free leads from the toggle to the lever switch.
Connect one to the common tab (marked C), closest to the
lever’s pivot. Connect the other lead to the normally closed (NC)
leg, farthest from the pivot. Don’t connect anything to the
normally open (NO) tab in the middle.
3d. Solder the battery pack’s leads to the 2 legs at either end of
the toggle. The circuit is complete! Test it by loading batteries
into the pack. The motor should run, the toggle should reverse its
direction, and the lever switch should shut it off in one direction.
If it all checks out, remove the batteries, leave the toggle thrown
in the direction that the lever interrupts, and mark or note this
direction on the motor.
4. ASSEMBLE AND ADJUST
4a. Drill a ¼" hole in the machine side of the lid, at the toggle
position you marked in Step 2f.
4b. Fit the toggle switch up through the hole, positioned with the
toggle thrown in the direction opposite the lid cut. Don’t glue it
100 Make: Volume