The Hudson

The Aster Hudson as received

The Aster LGB, Hudson Class locomotive represents the 1st of the J-3a builds of the Hudson locomotive. The real Hudson J-3a locomotives were built by the American Locomotive Company (Alco).  The model is all metal and was built as a limited production of 600 units;  Each unit is identified with its build number by a brass label on the bottom of the locomotive, and on the handsome wood box that it was sold with it.

The Hudson Class locomotives were originally commissioned by New York Central and designed as a 4-6-4 to support the weight of a larger boiler & firebox.  It was designed to replace the 4-6-2 Pacific, the 4-6-4  with the larger firebox and boiler allowed the locomotive to have more tractive power and running distances while maintaining full steam at higher speeds. The main advantage over the Pacific was its tractive power and ability to maintain it’s steam over longer distances.

The Hudson was named by New York Central after the Hudson River, with the Road number 5405 being identified as the first J-3a built for New York Central.

There were a total 275 Hudsons with only 50 of them being J-3a’s. All  ALCO produced Hudson Class locomotives were scrapped by the late 1950’s
There are several other 4-6-4 locomotives, they may be called Hudsons, however, the only true Hudsons were built by Lima and Alco.

Additionally, many Hudsons received stream-lining dress-ups, enduring the locomotive and captured the hearts of the masses, and can be found exemplified in popular media.

J-3a Hudson on display at the 1939 Worlds Faire, named Dreyfuss

The Aster / LGB model is highly detailed and shares many of the same parts with the live steam version produced by Aster.  The model was designed to be relatively easy to service, through the placement of the analog main board and sound card in the tender, while providing easy access to main electronics replacement. – the model includes a couple of tools, to do this with. While I can not be sure, I believe the original paperwork included with the model describes how to access the various items such as the lights and original smoke generator.

Here is the basic build info with photos of changing an upgrade from an analog sound card to a DCC decoder with sound.

The Decoder I used is a Zimo MX699LV with a Zimo smoke generator, I did retain many of the original connectors, the Firebox flicker IC, and all of the original lights.

here’s a couple of photos of the original electronics


To install the decoder I removed most of the original electronics and built new protoboards, with a socket for the decoder, and plugs allowing me to retain original wiring without cutting the ends off.  This also allows for future expansion of things like more lights and smoke generators.  As part of this I relocated the decoder into, what would effectively be the firebox, this allowed me to remove one of two ribbon cables that connected the locomotive to the tender.

each board was tested, ensuring that solder joints did not short or have bad connections. – the following photos are of the board in different stages as well as testing.

While I had both the tender and locomotive torn apart, I also upgraded the main speaker  from a generic speaker to a nice Visaton FRS 7 speaker and installed a speaker in the boiler  the below photo shows the new protoboard, speaker, and the old soundboard mounted, as a place to store it – The locomotive can now be run without it’s tender, however, it is not advised as the power pickups are not reliable.


While working on The Hudson I also fixed a crack in the coal load, repainted it and plugged the hole where one of the ribbon cables was located removed one of two original ribbon cables connecting the locomotive to the tender,  this too was painted, it’s just now shown in the photo.

Then finally, the smoke generator, I played with a few different ideas for mounting, finally settling on using the original wiring and screw mount terminal for the head light and original smoke unit, mounting the new unit on the floor of the boiler behind the screw mount terminal, then connecting some tubing between the smoke unit and the smokestack.  at this point, I also ran new wires for the headlight, while making a new connector, allowing it to be easily changed as it was designed.  For ease of servicing, I painted the terminals the respective colors of the wires for the smoke unit, those same wire colors are used on the protoboard to connect to the decoder.  – the new speaker is attached to the opposite side of the smoke tube grill, in the back of the smoke box.  The grill is a wonderful detail, that is not normally seen.

Then finally, some more programming and testing of the new decoder. Here’s
a two-minute video showing the locomotive and smoke generator in action.




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