Motorizing a Mini Model Locomotive

Model trains have entertained young and old alike for generations, pulling miniature freight and passengers from point via electric power. YouTuber diorama111’s 1:150 scale (48mm long) train engine didn’t come with a motor, or even gears, so he set out to add this capability, enabling it to move independently.

To accomplish this task, a central shaft with two worm gears was added, along with corresponding gears on both of the locomotive’s axles. Driving both simultaneously allows for smoother movements, and as seen around 3:50 in the video below, it can stop very quickly and even reverse as required.

Power is supplied by the smallest motor dioramma111 could find, with a 3mm height and 4mm width on its side. The motor, gears, and other control components are all nicely hidden in the body of the train.

The newly-augmented locomotive's main control board houses an ATtiny1616, which was made long and thin to fit inside the main boiler. A DC-DC converter and an inductor are hidden inside side tanks, and a supercapacitor was added to even out any power dips. Control is through an IR transmitter/receiver, and the locomotive even features a pair of headlights that provide a bit of extra luminescence to the project.

While specific build details are slim, the results are quite beautiful. Perhaps it will provide a few ideas and/or inspiration for those that want to step up their model train game!