Handlaid Code 40 Turnout

My decision to use Code 40 for the WR&N III mainline meant having to hand-lay the turnouts. Previously I had heat-bonded Code 55 rail to wooden ties with Pliobond; then I heat-bonded Code 55 rail to styrene ties. However, I could not see either approach being ideal for Code 40 rail. Instead, soldering the rail to PC board ties seemed like the way to go.

While I knew most modelers interspersed PC board ties among wooden ones, I thought this might look inconsistent. I also liked the idea of having the delicate rail secured to as many spots as possible. And so I started carving up a sheet of plain PC board into tie-sized strips, cut them to length, and bonded them to a rectangle of 1/8-inch thick sheet styrene.

When it came time to create the points, I wanted them to pivot like real ones, and also to have a more realistic and reliable throwbar. After fabricating each point rail, I drilled a hole up through the base at the pivot end, and soldered a length of 0.010 brass wire into the hole. Then I flattened the end of some more brass wire by squeezing it in a pliers, and soldered the flattened end to the top of the rail base near the end of the point. I trimmed this wire to length and bent it down at 90 degrees.

After inserting the pivot wires into holes drilled through the appropriate tie, I bent them at 90 degrees immediately below the styrene substrate and angled them such that the point rails were naturally sprung away from the stock rails. The short bent wires on the ends of the points dropped through a small slot centered between the points, and pressed lightly against the tip of a microswitch lever that poked up from underneath the substrate.

This admittedly unorthodox approach resulted in a distinct advantage: elimination of the age-old problem of broken throwbar solder joints. The reason this happens is due principally to the geometry of a point assembly—stresses are always induced in the throwbar solder joints because each point rail has its own pivot, and do not move in unison. The tiny size of the solder joints only exacerbates the problem. In my design, there is actually no throwbar in the classic sense; the point parts are not physically bonded directly to anything.

So, how does the turnout work? The microswitch is located such that the points are held in one position; pressing the microswitch lever changes the route and also sets the proper polarity of the frog. The turnout is actuated by a piece of plain spring wire connected to a Tortoise switch motor that presses against the microswitch lever; there is no connecting linkage between the switch motor and the point assembly or any of its parts. This complete lack of direct linkage eliminated an almost universal source of frustration: fine-tuning linkage until the turnout functions properly. It also avoided any possibility of applying excess force to the delicate point assembly.

The only aspect I don't like about this design is the appearance of the slot centered beneath the throwbar, which I thought would be tricky to disguise. I addressed this issue with my next turnout project, a handlaid Code 40 crossover.

Construction was completed on 19 May 1991, and it was installed on the "floating doughnut" layout about a month later. Click the images along the side for larger versions and additional construction details.

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