The Randall Museum in San Francisco hosts a large HO-scale model railroad. Created by the Golden Gate Model Railroad Club starting in 1961, the layout was donated to the Museum in 2015. Since then I have started automatizing trains running on the layout. I am also the model railroad maintainer. This blog describes various updates on the Randall Museum Model Railroad and I maintain a separate tech blog for all my electronics & software not directly related to Randall.
2025-08-23 - Dashboard Update
Category RandallA lot of the work I do on the layout and its automation has to do with maintenance and “invisible” infrastructure -- things people don’t see at all, but keep the entire thing running. In software development, we call these tasks “KTLO” (a.k.a. “Keep the Lights On”). Part of the invisible part of the Randall Model Railroad Automation is all my remote monitoring of the automation. I can keep track of what the trains are doing, if they are doing it properly, with notifications when things don’t run as planned, and I can (in a limited fashion) remotely operate the trains if needed.
As such, I spend about the last month working on an entire new dashboard infrastructure, which results in a web page giving a dashboard like this:
This page gives me an overview of which computers are on, wherever the automated lines are active (the “toggles”), and which train ran last, and whether it completed its run properly.
I recently expanded that dashboard with a “performance” tab that lets me see how the trains behave on their respective route:
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Affected |
Summit Mainline Track, Turnout T370. |
Description |
Gap and dip in the mainline track (which was held using hot glue!) |
Summary Fix |
Removed the obsolete turnout T370, replaced 4 feet of mainline track. |
Description of Issue
The top of the mountain is an area known as “Summit”. The mainline has two sidings around the mainline. The siding B372 has never been used and both turnouts on either side are non-functional. It now contains a little station which is where the Automation Passenger Train stops and reverses. The siding B371 used to work fine, and although it hasn’t been used in a while, we may restore it at some point.
A view of the mainline track to be replaced -- from before the bridge up to the first turnout before the signal bridge.
Just before turnout T370, the mainline track was of sub-par quality. There was a couple millimeter gap in the track, and it was held in place using hot glue. Once in a while we would get derailments there, and at some point we got a dead spot, and I did some repairs back in 2018.
Turnout T370 had been the cause of derailments in the past and I had spiked it. Anyhow, the Fulgurex motor underneath was disconnected. Here’s how I left the track back in 2018, and you can see the poor track alignment, and that’s when I was amazed to find the track was held using some hot glue:
Back in 2018 when I soldered that bonding wire to fix the track continuity problem, I was surprised when the part below the solder started melting and that’s how I discovered that this was held using hot glue. It must have been done a long time as it had blended with the rest of the scenery. Anyhow, as I wrote back then, that bonding wire was supposed to be a temporary fix. And now we’re finally circling back and taking care of it.
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2025-07-27 - RDC Update
Category RandallSince only one of the two Santa Fe RDC engines currently runs satisfactorily, I’m currently running a little experiment with matching Santa Fe RDC 191 with the SP 10 RDC:
That combo works well. I checked and both engines are correctly speed matched. It’s certainly a non-prototypical setup though. I had previously run them together as an April’s Fools joke.
On the workbench, I got a new duplicate of the UP GE 9538:
UP 9538 has been diligently working the mainline since May and, although I initially had some reservations on the TCS decoder, I got it working quite satisfactorily. I decided to have an exact replica -- same engine number, same motor -- so that I can just trivially swap them every other month without having to reprogram the automation every time. That should help give the engine a much deserved break.
I also got a new UP SD40-2. This is an older Bachmann design with an Econami decoder. From experience, these work quite well. I’ve tested 3450 on the mainline, and it seems very adequate. I’ll program it in the automation soon, giving me one more engine to swap from time to time.
The Santa Fe RDC 191+192 that I put back in automation is giving me some issues. It just keeps stopping from time to time in the tunnel before YouBet or the tunnel to the branchline canyon. Then, much later, it seems to respond to DCC commands again yet at the point the automation’s recovery mechanism has already given up.
Today I went to see where it got stuck and I noticed that one of the two cars seems to have no power, and the other car is not powerful enough to drag both units -- that’s to be expected since I “downgraded” these engines from two to one motor per car, so they don’t have a lot of pulling power. Thus right now I’m just going to run this as a single car train and monitor how that works. I may want to upgrade both engines with a LokSound “Capacitor / KeepAlive” to see if that helps.
The UP Passenger has this nice UP Observation/dome car provided by Jim, which has recently started to derail:
It consistently derails when going in reverse on the same spot over the T311 turnout. That area is very hard to reach -- farther than arms’ length -- so I can’t just get close and look carefully at the wheels on the turnout. It does also derail when I run just that one car with the same engine:
One suggestion from Orion was to turn the truck around, so I’ll try that another time.
The older and more “primitive” dome car works well, so the UP passenger train is back to having a single car:
The Rapido Santa Fe RDC 191+192 is back on the Branchline automation:


