Electric locomotive for Ikea Lillabo/Brio train (USB rechargeable) — v2.0

cults3d

I wrote an Instructable about how to build this Locomotive. This is the second iteration of a locomotive inspired by MilanGajic's work. I wanted it to be as compact as possible, fitting in the Lillabo tunnel while looking like a kid's idea of a locomotive, with a nice cow plow at the front end. The switch is the funnel. Turn it right once to turn the light on, twice to turn the light + motor on. You should print the base, engine, cabin, chimney part once and the front_wheel, spacer, and rear_wheel_groove part twice. The rear_wheel part has small teeth instead of a groove for the rubber band. With two rubber bands as tires, the rear wheel has enough traction to pull several Lillabo cars or even climb the bridge. Use loco-rear_wheel_groove.stl to put a tire; use loco-rear_wheel.stl for the older version with less traction. The front wheels are wobbly on their axle: this is intentional, helping the locomotive stay on the track during curves. Assembling this part involves screwing the spacer part onto M3 bolts, then assembling the wheel on the spacer, and finally attaching it to the base. Extra parts needed include a small rotary switch; I used a 2 pole, 3 positions switch (but should have ordered the 2 poles, 4 positions version). A one 5mm LED and a matching resistor are also required (I used red and 200 Ω). A T-shape DC motor, small lithium-polymer battery, micro-USB charging module, 12mm ring magnet, round-head 4mm bolt & nut, two M3 bolts for the front wheels, and a M4 bolt for the ring magnet are also necessary. Solder and heat-shrink wrap are required for insulation. The LED is wired in series with the resistor (see photo) and this is wired in parallel with the motor. Photos of the rotary switch show some of the wiring. The positive pole of the motor should be the upper one, regardless of its position. If you rotate it by 180° around the locomotive axis, the "upper/lower" poles are switched, but the rotation of the motor is also reversed. The wheels and spacer parts should be printed twice.