Page Originated 12/2012
Last update:

MAKING YOUR LOCO MODELS LOOK AND
RUN THE WAY YOU WANT

The Value of Testing

The models I work on must run as well as they look so they are subjected to thorough testing to ensure that you will be happy with the model you take out of the box from me. Commonly discovered during testing are insulated wheels that rub on a painted uninsulated part - when the paint wears through a short happens. An example of an uncommon problem is a loco whose uninsulated driver centers were clear coated at the factory and the clear coat became insulation; this was discovered when the loco stalled on a dead frog because only one driver of the three uninsulated drivers was actually uninsulated..

Test Criteria

For it to be acceptable to be returned the customer the model must run continously for 15 minutes without any electrical, mechanical, or tracking issues in each of these scenarios:
  1. Facing forward clockwise, 15 minutes going forward, 15 minutes going backwards on the 60" radius oval.
  2. The same on the 48" radius oval if that radius isn't too sharp for it.
  3. Turn the engine 180 degrees, repeat.
  4. The engine will be loaded with either a 9 car freight train, or one or more drag sleds, depending upon what it is capable of pulling.

The Shop's Test Loop

In my shop I have a test oval for running models. It consists of two concentric oval loops. The rail is spiked directly to Homasote. All radius numbers provided are centerline radius.

One loop is traditional O gauge track, 60" radius .125 steel rail.

The other loop comprises several gauges laid with code 100 nickel silver rail. The gauges are traditional O gauge, Proto:48 gauge, On3 gauge, and S gauge.

With rails to support running 4 gauges, the centerline radius of each gauge is;

  1. O gauge: 48"
  2. On3 gauge 47"
  3. Proto 48 gauge: approx 46 3/4"
  4. S gauge: approx 46 5/8"

This photo shows P48, On3, and S Trucks on the loops; the leftmost two rails are O gauge.

There is a 48" long straight section between the two half circles with transitions between the curves and the straight taking up some of the straight.

  1. There is a switchback crossover between the two loops, starting with a #6 LH turnout on the 60" radius loop with the through route continuing the loop and the diverging route connecting to the frog end of the #6 switchback turnout.
  2. The through route of the #6 switchback turnout continues on to a storage track.
  3. The diverging route of the #6 switchback turnout conntects to a #6 LH turnout on the 48" radius standard O loop. A transition from code 125 rail to code 100 rail is built into this connector.
  4. The through route of the turnout on the 48" radius loop continues the loop. The diverging route connects to the diverging route of the aforementioned #6 switchback turnout.
  5. The turnouts of all frogs were intentionally left dead so that certain pickup problems can be detected.
  6. The Proto:48, On3, and S loops do not pass through the turnout since their outer rail is the other side of the inner rail of the standard O loop.

Here is a view of the switchback.

All the track was hand laid. Great care to make it perfect was NOT taken. My view is that not all customers' trackage will be perfect, so the model must run without issues on that trackage. While each loop is in gauge, the curves are not perfect, the inherent unevenness of Homasote creates uneven track, and the individual sheets of Homasote have boundary issues. All this creates a demanding running environment for models; models that run here should run reliably on all but extremely poor trackage.

Test Loop Controls

I use a modified DCC setup for controls. To test DC powered locos an NCE 4 amp decoder is powered by DCC and its DC motor output replaces the DCC power on the test loops.

Two DCC systems are used.

When I am present while trains are running I use the NCE PowerCab, partly because I prefer it for programming.

When I am elsewhere in the shop and models will run unattended, I use a Lenz system which I have modified so that a remote/wireless garage door opener that I keep with me can stop trains. This modifiction is described here.

I also use a display that shows current and track voltage to monitor locomotive performance and to watch for issues on initial running.

The display is an Alpha meter that was manufactured by DCC Concepts.

Interested in learning more about 2-rail O scale? Please visit the O Scale Kings web pages.
These web pages were designed and implemented by Rod Miller.
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