As I was test-running a loco over a turnout that I had just hooked up to a Bullfrog turnout control, I noticed that the wheels seemed to be picking the points when the loco was reversed. This seemed unlikely, given the fact that the Bullfrog holds pressure against the rails with the tension of its connecting wire. When I looked closer, I saw that my careful drilling-out of the center hole in the stretcher wasn’t careful enough, and the hole had gotten big enough to cause the stretcher to break in two.
So I have an installed, ballasted switch with a wire running up from the Bullfrog and through the stretcher, able to throw the point rails, sort of. But the point rails really are no longer entirely joined by the stretcher. How would you repair this? Will CA or epoxy bind the two halves well enough to stand the back-and-forth? Should I glue the break, first removing the turnout control wire, then redrill the hole and start over? Or should I relocate the Bullfroga bit and run the wire through a hole at one or the other end of the stretcher instead of the center? Or, say, fabricate a thin piece of metal or styrene and slide it under the stretcher (after removing the turnout control temporarily), gluing them into a sandwich for more strength, then redrilling the hole? Whatever you have to offer, I’ll be happy to hear about. Thanks.
Thanks to everyone for solid suggestions. I went all Occam’s Razor and tried epoxy, very carefully, on the break. It worked fairly well for a while, then separated again. So (like castle-building in Monty Python and the Holy Grail) I epoxied again, using more glue and including the switch machine actuating wire. That seemed to hold up, and I could have stopped. But remembering my own first idea–adding a strip of styrene to the top or bottom of the stretcher–I took another look at the turnout and got out an uninstalled one t
Reinforcing the bottom of the throwbar is probably the most durable/ lasting repair. Styrene would work, but a brass strip may be better. Since the origional ME throwbar is engineering plastic the bond should be made w/ epoxy regardless of the material used to “scab” the break.
A bit tough to do w/o removing the turnout, but doable, even if some filing is nec for some added clearance under the part. Once fitted then glued, a thin shim could be inserted to allow upward force, wedge shims to keep the point rails and the break closed, then weight the throwbar until epoxy dries. This should be stronger than the “stock” throwbar, just redrill the hole and install sw maching, good to go. As long as there is sufficient clearance under the repair, the point rails should move freely. That temp styrene “shim” once removed should give the clearance needed. Just use care it doesn’t get glued, maybe coat w/ grease for insurance.
Trying to glue anything with the turnout still on the layout will result in glueing the turnout TO the layout. The wicking action is too great. Trying to sandwich some metal/styrene on top AND bottom would require being able to file enough clearance under the tie to prevent binding/sticking.
There is no great amount of pulling pressure going on. Without having one sitting in front of me, you might consider using a couple wire hand grabs and use a solder pen to heat and push it into both halves, essentially stiching them together. a small dab of model glue should keep it locked together. Just don’t touch the tie with the iron, it’s just not a good idea.
If you’re speaking of the throwbar which ties the point rails together, I’d replace it completely with a piece of copper-clad board. Cut the copper foil to isolate the points from one another, then solder it in place, with the hole pre-drilled for the point control wire. Done properly, it’s unlikely that it will fail again.
What brand turnout do you have? Some makes have the points riveted to the throw-bar so they can pivot. If this in not the case the PC board repair is the best bet. I think you can purchase pre cut PC ties or cut your own.
Forgot what the ME’s look like exactly but have done this on a Shinohara once or twice by replacing the existing broken piece with a new strip of styrene.
I’m at the boundary of my competence and experience here, but if you can hold my hand a bit:
Where’s the simplest source for “a piece of copper-clad board”?
I gather it’s that thin circuit board material that gets used for ties in various applications. I grasp the importance of cutting the foil, too. (Bully for me!) But then:
Exactly what am I soldering to what when I replace the ME piece with the new–predrilled; thanks!–one?
I’m thinking that it might be worth sacrificing a “spare” turnout to get a better look at its construction to answer that, and maybe to do a practice run. Are we talking about the soldering specs I use for installing feeder wires, say, or is this one of those relatively low-temp jobs such as would be used in assembling a circuit board?
Thanks for your advice, and to all the contributors for creative and thoughtful suggestions.
I believe that you can buy pre-made ties made from the copper-clad board, and they should have them in various lengths suitable for turnouts. However, you may have to buy a large quantity. You could also buy a piece of copper-clad board at any electronics store such as Radio Shack/Circuit City and the like, and simply cut your own.
While most of my turnouts are Atlas or Shinohara/Walthers, I just remembered that a friend had given me a bundle of turnouts, and among them are three MicroEngineering ones. Two have a two-piece plastic throwbar (which is likely similar to yours) while the third one is also two-piece, with the bottom one (the actual throwbar) being plastic, while the points are tied together (both mechanically and electrically) with a soldered nickel-silver tie bar. I suspect the latter one is an older version, while the other two are for DCC operation.
Anyway, what I’m suggesting is replacing the entire two-piece part with a single piece of copper-clad board. Depending on your set-up, it can be the same length as a regular tie, or, if you have operating switchstands which require a longer throwbar to actuate them, then somewhat longer so that it can extend outward as required.
If you need the point rails to be isolated from one another , remove the foil from the area where the actuating rod for your switch machine will be located, keeping in mind that the more foil you can leave in place, the stronger the bond will be between the foil and the board.
You’ll need to determine the location on the new throwbar where the point rails need to sit - since the one of which you’re speaking is damaged, check an intact one to measure the total distance which the points travel (measured at the throwbar’s location). Divide that measurement by two, then make two spacers of that thickness from wood. Clean the copper on the new throwbar, then pre-tin the approximate areas where the points will be soldered to it.
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