Santa Fe EMD F3’s A-B-B-A units


Respectively these units are numbered  24L, 24A, 24B & 24C. These models are very high detailed 1:32 or gauge one scaled models made by USA Trains of EMD F3 locomotives painted with the Santa Fe warbonnet livery, the owner wanted, Airwire RCC with Pheonix sound card installed in the units.  with custom 3d printed battery mounts, then additionally all of the lights upgraded to LEDs

here are the main items used:

The directions for the airwire drop-in were very comprehensive, with directions for taking apart the locomotive and where and how to mount the receiver, smoke power board, sound card and speakers, I took them a step further with the custom battery mounts, removing all power pickups and wires from the trucks then upgrading all of the lights to LEDs.

to tackle this I worked on two locomotives at a time, the 1st part was to remove all the electronics, then file out, the switch holes for the charging port, here is the underside where with the new charging port and power switches.


once that was done, I mounted the P8 and smoke board.  and temporarily mounted the battery to the last two units, then worked on how to connect the A & B units speakers.

This is when I came up with the idea of using a bit of heat shrink and some micro connectors to make the wires look like air hoses.


after that, we worked on the details for the battery mount, curiously the battery weighs the same as the weight, so, the new mount installs in place of the weight.  for the A units, the battery is installed in the rear of the unit and the voltage regulator was moved to the front, under the cab with a new heat-sink, for the B unit the heat-sink and voltage regulator was left alone and the battery moved to the front, here’s an example of the electronics and the battery mount. in this picture, the wiring isn’t completely done, the mount uses a zip tie to secure the battery in place.


After the battery mount was done, it was requested to upgrade all of the lights to LED’s each to this each locomotive was disassembled, then the lights desoldered, and replaced with LEDs, then tested.


I really need to clean my bench, its mess. Personally, I’m always amazed at the light difference that an LED puts out compared to the incandescents

here’s a brief video of showing the lighting differences

I made this video before the lighting updates and battery holders, but here is a test run of all 4 locomotives in a consist, with all 4 speakers
















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