M&K Junction Railroad

M&K Junction Railroad
Another train of eastbound coal crosses the Cheat River

Monday, April 26, 2010

The Curved Turnout

April's project was a curved turnout for the downhill (eastbound) track on the Cheat River grade. This switch is not shown on the track plan as it is an afterthought conceived as the layout was building. It will lead a track into the area next to the water heater where there will be either a coal prep plant or the Alpha Portland Cement factory. Neither facility actually exists (or existed) on the Cheat River grade; although the cement plant is across the river (approximately opposite the Tray Run Viaduct) on the former M&K subdivision of the B&O.

Was a curved switch necessary in this location? No. But the diverging route of a conventional straight-legged turnout would not have fit smoothly into the 68.5" radius curve of the main track here. I decided on a curved turnout because later on I would need some elsewhere; so it seemed like an opportunity to give it a try.

Construction of the turnout started with a template that I drew in TurboCad. It took some doing to figure out how to draw this in TurboCad. The template shows the gauge lines and the centerlines of the two routes. I constructed and printed turnouts with curved legs ranging from 68.5"/153" to 68.5"/168.5". The latter switch seemed to fit the geometry of the space best and the larger radius was a gentle curve. Surprisingly the frog angle measured out to about a #6.

The template printed out on my Epson 13"x19" printer if I glued two sheets of ledger size paper end-to-end to make an 11"x33" sheet and using custom size on the printer. Staples would have printed it out for $2.98.

Here's the beginning of the turnout with the stock rails in place. (I should have cut, soldered and spiked the frog first, but I got ahead of myself).

Now the frog is in place.

Closure rails, wing rails and guard rails have been added and a truck runs smoothly.

Close-up of the points.

Close-up of the frog, guard rails, wing rails (yeah, yeah the wing rails are different length - doesn't bother me, does it bother you?). After soldering the guard rails in place and filling the gap with solder, I found that I had a Dremel cutter that cut a flangeway to the perfect width and depth; although it threw chips of solder all over the place.

Straps soldered in place, ready to go to the layout.

Here's the initial fitting on the ties and roadbed. I glued the ties on before spiking.

Here's the throwbar and the head blocks. The throwbar was made out of perforated printed circuit board material (perfboard); I know that I had solid PCB material somewhere, in fact, I had found it just a few weeks before; but for the life of me I don't know what I did with the bag of it. The perfboard will need reinforcement. I also made another mistake here, do you notice it? In my haste (enthusiasm?) I forgot to pre-drill a hole through the roadbed for a switch machine. I'll have to use a Caboose Industries manual machine in this location.

Ties finished, ready for spikes.

The critical center section of the turnout spiked down. Note the marks where the gaps will be cut around the frog.

Here are two of the gaps cut and then filled with styrene ACC'd in place and filed to the rail profile. I fill all of my gaps that are for electrical isolation only. In this case I wanted there to be little chance that the gap would shift over time thereby mis-aligning the rails at this critical point.

Finished. All that remains is to solder on power feeders, paint the ties and weather the rail.


  1. When you need to drill a hole under existing ties for a switch machine, drill a small pilot hole down from on top then use a Fostner bit with a measured plung depth clearly marked and drill up from below.

    Nice job!

    You may wish to try using a Fast Tracks brand rail bender to make laying your job easier by pre bending you rails. Tom Thorpe

  2. Nice work. Another technic than fasttrack one.
    Thank you To share.

  3. Nice work. Another technic than fasttrack one.
    Thank you To share.