Saturday, August 31, 2013


Most model railroads require as much time spent below the layout surface as above it.  Typically, the “fun stuff” is at the surface and above (track, trains, structures, scenery), but vital elements are underneath: wiring and switch machines.  With track for the Eugene depot and classification yard laid, the past few weeks have been spent in “the land down under.” 

Fifty-one switch machines—both Tortoise ™ power machines and Blue Point manual throws—were installed for the Eugene switches. 

Wiring is now underway with the depot tracks complete.  The depot tracks comprise a single power district connected through a PSX circuit breaker.  The depot tracks are divided into ten power blocks, with six of these blocks wired for potential detection.  Detected blocks require the block sub-bus to maintain separation between its two wires.  “Dark” (undetected) tracks have block sub-bus wires “gently” twisted.  Proof of successful wiring can be seen in the photo where the loco is lit and a DCC brakeman (made by former “DCC Lunch”-mate John Plocher) has a lit lantern. 

Eugene Depot tracks wired.  Depot tracks are the four furthest tracks in plus the industry spurs between the depot siding and the backdrop.

As I began to run the test loco on the depot tracks I had to trim the switch machine throw rod projecting through the throwbars.  I clipped the music wire rods close with a hard metal nipper and then trimmed them the rest of the way with a cutoff disk.  Therein lay a problem.  I recently replaced the Sears motor tool I used for five decades with a new two-speed Dremel.  The high speed for the cutoff disk produced too much heat in the rod for the surrounding plastic throwbars of a pair of commercial turnouts.  These were among the few remaining Micro Engineering turnouts I had in stock after my switch to Fast Tracks jig-built.  They are just visible on the left side of the photo of the depot tracks, in front of the brakeman.  The throw rod heated up by the cutoff disk melted right out of the throwbar.  This is a potential problem for any commercial turnout with a plastic throwbar.  I just encountered it following my change of motor tool (presumably with a higher speed). 

Original plastic switch throwbar has a melted out hole for the throw rod.

The melted out hole in the plastic throwbar necessitated a throwbar replacement.  I’ve had to do several of these for various reasons.  My experience with Fast Tracks jig-built turnouts means I have the skills, tools and materials to do such replacements quickly and easily.  Two new printed circuit (pc) board ties got insulating notches filed in them.  The original plastic throwbars were removed and the new pc-board ties inserted.  The switch points were then soldered to the new throwbars.  The switch machines were remounted with new throw rods (A longer throw rod is needed to aid the installation process.).  The new rods were trimmed and I now have two fully functional switches.

Turnout with replacement printed circuit board throwbar installed.

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