KATO 7008-5


12/31/15- Yet another locomotive for the Consisting Project. The point of the project is to share resources (the sound cars and coaches) with different locomotives, singly or in multiples; to date, it's five locomotives for two sound cars in two coach sets (Orient Express and Showa-era Imperial coaches).

There's really not much to say about the DD51 that hasn't been covered in previous articles (DD54 and EF81-81). Under the skin, the design/construction are substantially the same, so the motor/light decoder installation are substantially the same. There are relatively minor design differences in the construction of the locomotives; though minor, those differences can be vexing when disassembling the locomotive, or trying to reassemble it with the decoder installed... and have the body shell pieces fit!

In this case, the final disassembly step (removing the trucks) was similar to the DD54, where the metal frame halves had to be pried apart along the bottom with the bottom plastic frame still attached so that trucks could be removed, so the bottom plastic frame could be removed. Not the most disassembly-friendly design, but once you figure it out, it's relatively simple.

The bottom of the metal frame has no openings to the interior, so slots had to be cut to route wire from the power contact strips up to the decoder. The best place to do this is at the center of the contact strips, which happens to be where the interior space for the motor brushes is located.

Topside, where the light circuit board was installed, there wasn't anything to mill for recessing the ESU LokPilot Micro decoder, except for the plastic housing on top of the motor. This was a futile exercise since it didn't create enough space for the decoder to fit under the floor piece of the center cabin. The floor piece was designed to serve as a clip to press the light board's power contacts against the motor, so it wasn't needed for the decoder installation. To fit the decoder, I left the floor piece out (which is why the wiring is visible in the photos-- in person, without flash illumination, it's not noticeable).

This time, I used a wired decoder instead of a plug-in (because that's what I had on-hand). Having to splice wires with heat-shrink tubing created a space problem: There was very little room to stuff the additional wiring, which probably contributed to the problem of fitting the cabin floor. It also made it more difficult to solder since spliced wires need to be long enough to manipulate for soldering, with a short piece of heat-shrink tubing pre-installed and ready to slide into place. The plug-in decoders with rigid pins to solder onto make for a more compact and quicker soldering job.

Another difference was that there was practically no possibility for installing taillights-- actually, quite a welcome relief, considering how much work that can entail! The taillights (clear red plastic tubes) are mounted low on the removeable railings, which attach to the lower plastic frame, with no practical place to install LEDs nearby. Fiber optics? Maybe for the die-hard tinkerer, but not me!

As with the DD54 and EF81, I believe that Digitrax makes a drop-in decoder that doesn't require any soldering... but where's the fun in that? Admittedly, it would probably make hiding the innards easier...

I believe that using ESU decoders in all my trains streamlines decoder configuration (using their LokProgrammer) since I can clone configurations and tweak them in a consistent interface. I prefer not having to figure out how different brands want you to configure their products. Besides, ESU makes a great line of decoders that are powerful, reliable, and easy to tweak. Regardless of brand, a generic decoder and soldering skills will let you install a decoder into almost any locomotive-- wires and solder are the universal decoder interface.