Model Railroading > Chasing those layout building gremlins

   Chasing those layout-construction gremlins is a natural part of building a layout. A couple of recent wiring and tracklaying problem examples I went through may help someone experiencing a similar process.
 
   Our Sugar Pine Lumber Company/Minarets & Western Railway layout (photo 1) uses code 70 and code 55 flex track plus ready to lay switches, mainly Shinohara but some Micro Engineering. I’ve been working on a small town area, going through the usual process of laying track, installing switches, adding Tortoise switch machines where appropriate, cutting gaps, dropping feeders to the Lenz DCC bus and so on. I test frequently and run a locomotive over a “work zone” after a few feeders are added as it’s a lot easier to chase down problems when there’s only a few changes made since the last successful operation.
 
   I did my tests, everything was fine, and left to eat lunch. Came back, did a bit more work, and – zip -- a dead short. Checked the work, checked the new feeders, disconnected the feeders one at a time (I wrap the wires to the bus but don’t solder them until the system is solid and functioning well) and still no luck. Did the usual, looked for tools across rails, wire scraps in the wrong places, nothing. Threw the work zone switches and those nearby to look for other electrical interference, nothing. Frustrating at best.
 
  While tidying up a bit, using my magnetic tool to grab the stray spikes in the work area and the town in general, I found one that had worked its way down between the stock and closure rails on a switch far away from the work area (photo 2). It was down there where it wasn’t readily visible but was shorting the two rails together with the switch thrown one way. (Note: Yes, I know, if this switch was a so-called “DCC friendly” switch this would not happen, but the switch is not, so it happened, first time in many decades of building layouts this way.) The simple lesson is look for the non-obvious things when chasing those shorts.
 
   The second situation (photo 3) concerned a switch that had erratic electrical problems. The wiring was right, the point power routing was correct but also erratic judging by the indicator LEDs on the Frog Juicer, it just gave my test locomotive fits. I had solvent-cleaned all the rails in the area so that wasn’t it, or so I thought. This switch was one I had inherited when a senior relative died and I received his train material. It was a brand new Shinohara switch, still in its original box dating back to the 60s or early 70s.
 
   Even in a clean, dry environment the nickel-silver rails will slowly oxidize, and the cardboard box in contact with the rails can transfer some paper-manufacturing acids to the rails over the decades. The rail heads look good, albeit with a very slight yellowish tint, but electrically they stink. I took my Homasote track cleaning block to the rails wrapped in 1,000-grit wet/dry sandpaper, applied wet, followed by 1,500-grit as a final polishing step. This is the same process I use for cleaning the rail heads on Micro Engineering pre-weathered rail. A folded-over piece of the sandpaper was also used to clean the spots where the points contacted stock rails. That immediately eliminated any electrical pickup or power-routing problems with that switch. The moral here seems to be just because it’s new doesn’t mean the rails are ready for the road.
 
For what it’s all worth…
 
Jeff Johnston
www.trainvideosandparts.com (videos are great Christmas gifts!)
 

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NIce job figuring it out. I sure hate those mysterious shorts.

The secret to electrical troubleshooting, change one variable at a time. Helps keep you from losing all of your sanity.

I had a very similar incident. I did a whole bunch of trackwork involving several switches only to find a dead short. I had to cut some gaps and disassemble some of the trackwork to find a defective Atlas switch that contained a short in the frog. That was a very frustrating time.

Ted Curphey
Ontario, OR

I, too, had a similar incident.  Took a vacation day to focus on tracklaying; installing about 6 Peco and ME turnouts at one end of staging... in my focus to lay track I completely forgot to break out the voltmeter to see which turnouts were DCC friendly or not? Took awhile to find all of the shorts and modify all of the turnouts. Lesson learned!

Then there are the days where the layout runs perfectly, but the following day everything goes wrong. The Gremlins are out in force and drive you to the brink of taking a chainsaw to the entire layout. Then, the very next day, everything is working perfectly again.