Test Switch

It’s become fashionable to call the throw bar of a switch by its proper name: switch rod. Now, I’m all for using the correct terminology, but it seems to me that calling the giant chunk of PC board that keeps model switch points the correct distance apart gives these abominations more credit than they deserve. If, on the other hand, we call it a throw bar, and conceal it somehow, we give ourselves an opportunity to create a nice model of the switch rods themselves.

Switch and Throw Rod

On previous turnouts, I hid the throw bar below the benchwork, and connected it to the points with stout droppers, whose ends were filed to look like switch rod brackets. This worked, but I’m eager to try something new.

My new plan is to print a combined throw rod and pair of switch rods, and when they arrive, I’ll be sure to share them. However, they’re not here yet, and being an impatient sort, I’m pressing on with exploring my backup plan. I’m pleased to say that it appears to work, though with a little more fettling than I’d like.

The parts for the throw rod and points are shown below. Proto:87 Stores reinforcing bars stiffen the webs of the points. Upon reflection, I believe I installed them backward. Facing the other way, with the smooth section closer to the toe would provide an area where the switch rod brackets would sit. The reinforcing bars fit perfectly on the web of the code 55 rail, and they’re a doddle to solder in position. Having said that, my best photo of a Canada Atlantic switch seems to show a complete lack of these parts!

Switch and Throw Rod

The throw bar itself is the piece of styrene (ABS or something more robust if I do this for real) with two grooves that connect with the phosphor bronze wires soldered to the foot of the points.

The key to the assembly is the first tie after the toe of the switch, which is only a half tie. The bottom half of this tie is missing, and the throw bar slides in that space, trapping the wires from the foot of the points against the roadbed.

So far it seems to work. Getting the diverging point to sit flat was the most challenging part as the assembly seems to be sensitive to over-tight wire to throw bar connections.

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