Monday, April 15, 2024

Trackwork wars, Part 13

I'm pretty much done with the previous challenges described in this series, but one more interesting one did surface during my last operating session. There’s an old saying, that using a layout inevitably breaks things. Well, this was another demonstration of that adage. (For previous series posts, see for example: ). I’ll describe the issue because it was not a simple problem.

The interesting aspect of this particular problem is that it involves several different things. First, it’s a really old switch, dating back at least 40 years on the layout. (It’s one of the Russ Simpson “Scale Model Railroad Trackwork” No. 5 switches, wonderful components, and if I had managed to buy more of them, I would have used them throughout the layout. The point rails are all in one piece, from frog to throw bar.) 

Second point, I had had problems years ago with electrical performance of this particular switch, which relies on the contact between point rails and stock rails. I had solved this many years ago, by adding the contacts of a micro-switch under the layout with an operating wire up through the layout and into the hole in the center of the throw bar. Movement of the points moves the wire, which moves the contacts to the appropriate connection.

In the photo below, the switch point rails can be seen to be joined by a brass strip, to which they are soldered. In the center is a rivet which attached the brass strip to a plastic throw bar underneath everything. Or there was. It broke at the rivet, and the two pieces are lying parallel to the track, just above the points. The throw bar in turn has a hole at one end (at left in the view below), which was the connection to the (un-mounted) Bitter Creek ground throw which is at upper photo center.

My first shot at fixing this was to try and glue the left half of the throw bar (as you see it above, at left), back into place under the brass connector strip. This worked, but didn’t survive many throws. It was clear I needed to make an entire new throw bar.

I chose some Evergreen scale 6 x 10-inch styrene strip, and cut a length equal to the original throw bar. I then rounded the corners and drilled two holes, about no. 55, one in the center (to accommodate the wire activating the micro-switch contacts below the layout) and one near the end, for the ground throw. And I painted it black.

It wasn’t easy to slip the new throw bar under the switch points and over the center wire, but I got that done. There was a slight bend in the frame of the Bitter Creek throw, so I temporarily replaced it with a Caboose Industries throw, just to get it back in service.

This works well enough, and for now will remain this way. I was glad to be able to keep the successful electrical arrangement on this switch, while replacing the throw rod. The test will come, of course, when visitors operate through this switch, as they will repeatedly for almost any switching task at Shumala. Fingers crossed.

Tony Thompson

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