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I picked up this HO brass Oriental Limited 2‑4‑4‑2 Mallet on eBay for a great price. It was listed as non‑running, but once I tore it down I found the issue right away—an exposed wire causing a short. Easy fix.
I’m planning a full DCC upgrade. Based on the tender measurements, an ESU decoder, capacitor, and cube speaker will all fit nicely. After removing the tender shell, I discovered a brass sub‑floor that had to come out to make room for the DCC components - removed with a Dremel metal saw. Drilled holes for sound. I installed a styrene floor to give me a clean mounting surface for the speaker, and I’ll add a second styrene level to support the decoder and PowerPack.
I’ll also be installing LED lighting for the headlight, cab, and a flickering firebox to bring the locomotive to life.
... tender modifications ...
... styrene flooring and speaker mount ...
... the tender trucks were mounted in an unusual way—held in place by pins. That setup wasn’t going to work for what I have planned, so I’ll be replacing them with Kadee trucks equipped with electrical pickup and screws ...
... I’ve started adding detail to the locomotive shell, beginning with the cab window frames and interior. I’ll also be adding backhead detailing to bring the cab to life.
Installed the new electrical‑pickup trucks and fabricated a clean housing inside the tender to hold the decoder and all the components.
Because this locomotive is brass, the tender is already isolated, and I’ve now spent plenty of time isolating the motor as well—tracking down nearly every remaining continuity point. The only issue left is the mounting bracket, since the motor is attached with metal screws and that’s still conducting. I’ve ordered nylon screws to eliminate that last source of continuity.
In the meantime, I shifted to planning the wiring layout in the shell and working on the lamps. I drilled a hole in the main locomotive shell for the wires that will run to the tender through the JST connector (added a shrink wrap to prevent wires cuts), and I also drilled the openings for the front and rear lamp LEDs. I painted the interior of the lamp housings silver, and I made small plastic washers that slip over each LED to hold them securely in the lamp bodies and a preventative measure for a shortage.
Very cool loco, and nice work!
Installed the LED in the rear lamp, soldered the PowerPak to the decoder, and added JST connectors to the speaker and the truck pickup wires. I also test‑fit the tender shell, which now seats snugly with no clearance issues.
I replaced the metal screws with nylon ones (painted black) for both the motor and the trucks, and to eliminate any chance of a short I wrapped the motor in Kapton tape. A multimeter check shows no continuity anywhere between the motor, the frame, or the pickup wheels. Eventually I’ll add a copper strip and solder a lead for left‑side pickup, since the original brass design relied entirely on right‑side pickup for the engine. The tender is already set up with full right‑ and left‑side electrical pickup.
I’ve got the harness started on the tender side with the JST female connector, and I’ve finished the decoder leads for track pickup, the rear headlight, and the speaker. What’s left are the wires for the motor, the locomotive’s rail pickup, the front headlight, the cab interior light, and the flickering firebox, all of which will run to the JST female connector
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