I should know better than to say things on this site like ‘I’ll post tomorrow that…’ or ‘Next week I will…’. I’m a grad student, which means I don’t really have a lot of time, generally speaking. Things slip, it’s a fact of life. Modeling hasn’t slipped so much as blogging. Which means I’ve done a lot that I haven’t written about yet. Last weekend I started my first DCC decoder install…and this weekend I get to undo it. Maybe. We’ll see.
I purchased a Digitrax DZ143 decoder to install in my Kato 6043 KIHA 110. I thought such a small decoder would be easy to hide in the car’s toilet…but these things are much larger than I expected. I don’t think I’ll be able to hide it at all. Anyway, I broke the install up into parts: I haven’t connected the headlights yet. That’s a job for later. This post only covers the minimal installation needed to get the thing moving on the track.
The first thing to note is that this unit comes apart just like the Kato Budd RDC, with the exception of the light boards. We won’t be dealing with those today, and as they are attached to the top of the shell, we can safely ignore them. Instructions for disassembling that can be found on Kato USA’s website. Just pretend that’s your little KIHA instead.
The first thing to notice is that if you want to install the decoder in the frame, you’ve got a ton of milling work ahead of you. I have neither the tools nor the skill to mill my frame, and so unlike this guy, I’m going to have to be satisfied with a rather visible installation. The general strategy is going to be this: I will solder the pickup wires to the brass strips under the plastic interior; I will use electrical tape to isolate the motor pickups from that brass strip, and solder the motor leads directly to the motor pickups. I will note, so there’s a little suspense, that this works well as long as you don’t make the one goof I made.
Here are the motor leads soldered to the motor. I thought that I would be able to wrap these in electrical tape, but this was faulty thinking on my part. Get some heat-shrink tubing, really, it will be much easier. Something I didn’t think of until later is that I should have soldered the leads at a 90º angle to the pickups, rather than in line with them. When you are reassembling, you fold these pickups towards each other—but with the leads soldered like this, you will just short the motor out. Anyway, this will do as long as I leave them sticking straight up, but I’ll go back and heat shrink them later.
I had to put some small pieces of electrical tape in the frame to keep the now much more bulky motor pickups from shorting against it. Note that the tape sticks out a bit; it will be folded over the outside edge.
I hate Radio Shack’s helping hands. You can’t move the two hands any closer than they are, which makes holding small fiddly things together near impossible. Here I am setting the jig to solder the pickup leads to the brass strips. Have you spotted the goof yet? Do not solder the leads to the BOTTOM of the strips! Why? Because that’s where the contacts in the trucks touch the brass strip. I ended up causing the truck to bind: It doesn’t turn through it’s full range of motion. So: Solder the leads to the TOP of the strips, between the strip and the plastic!
Soldering complete! Something I didn’t adequately plan for, but which ended up being only a minor annoyance, was arranging the wires so that putting the pieces back together was not an exercise in puzzle solving. I wasn’t sure at first how to get the plastic interior between the motor leads without unsoldering one of them. I didn’t end up needing to do that, but it took a long while to figure out how.
Here it is, all assembled. I tested it first, of course, before spending 30 minutes trying to figure out how to tape everything down so that shell would fit back on. Notice how the decoder and wire harness are not only not invisible, but rather conspicuous? This is one of my remaining challenges, aside from wiring the headboards.
Notice the suspicious angle that the right-hand truck is at? Yeah, I didn’t see that at first either. But during testing, the darned thing kept de-railing. It was only then that I noted the truck was binding. Now I have to find a way to remove the brass strips and flip them over so the unsoldered side is up…hrm.
Anyway, the bad news is that after a couple of hours of otherwise flawless operation, the thing suddenly went dead on me. It doesn’t appear to be the result of a short, and so Digitrax told me I should send it in for warranty repair. I wish I knew what happened, though. Anyway, I’m removing the thing today—a shame, for how much effort went into installing it. I haven’t soldered in nearly a decade, and I cursed a storm while soldering; when I was done, I was really shaky and irritable. I don’t want to have to put my wife through that again!
Continue to the rather annoyingly mis-labeled next part of this article.