I have 2 switches on a flat hill plateau (built out of foam, which is 4 1/4 inches above the ground level (plywood). If I drill a shaft down through foam to the plywood, would a tortoise machine have enough strength to switch and hold the point reliably?
Alternatively, I can cut out big square access holes from beneath to the topmost layer of foam, upon which the switches sit, and glue the tortoise from beneath, no more than an inch away. But that would be more hassle, and I don’t know how well will the glue hold.
There have been previous discussions on this exact subject. I believe the concensus was that the tortise has enough strength but that the activating wire flexing could be an issue. As I recall the solution suggested was to use “music wire” in place of the “stock” Tortise wire…?
Alternately, Circuitron sells a remote mounting kit for the Tortise that employs a control cable system that allows mounting the Tortise up to 18" from the turnout. In fact. Using the remote mounts will allow one tortise to control two sets of turnout points! The mounts could be easily be used to animate all sorts of things. Pretty cool if you ask me. [:)]
Great, the music wire is what I suspected, but wanted to confirm - Tortoise manual mentions that as the distance grows, wire gauge has to be upped.
I am planning to get a remote mount as well - two of my ‘sea level’ switches happen to be situated on top/too close to a brace underneath to have a tortoise mounted.
This is one of several reasons I don’t want to “go there” with foam. I prefer the simplicity of plywood supported by risers rather than laying track on thick slabs of foam. I want something “rock solid” beneath my tracks, with no more than an inch separation (consisting of plywood and homasote) from a subterranian switch machine and the track switch. The greater the distance, the more finicky the connection.
I would run a brass tube from the turnout down to the Tortoise. Actually a tube inside a tube. The inside tube would be the torsion link from the turnout to the Tortoise, the outside tube would be the bearing. At the top of the inside tube, a piece of piano wire inserted into a drilled hole through the side of the tue and soldered. (The wire is perpendicular to the tube) The very tip end of the piano wire at the top would be bent down. This bend would be inserted in the hole in the throw bar. So, twist the tube, the turnout throws. Then do something similar at the bottom except the piano wire would have a loop on the end. Then build a link from it to the Tortoise similar to what was used on twin-coil machines. By using the inner brass tube as a torsion link, you get more transfer of motion for the longer distance. I would use 1/8 tube for the outside and 3/32 for the inside. The piano wire can be .032.
To hold the Tortoise in place, make a wood mount out of some luan or paneling. perhaps a three inch square or so. Or about 1/2 larger on all sides. Epoxy it to the foam on the bottom, then mount the Tortoise by the usual method using screws.
The link between the Tortoise and torsion tube piano wire can be a brass wire from .032 to .064 in diameter, and bent so it has a 30 to 60 degree angle when done, with a small loop at the center bend. Put a Z bend on one end to slip in the piano wire loop. The other end could have a small loop the screw of the Tortoise goes through.
Hi, I’ve had good luck using pianowire in a 1/8" tube to push/pull the switch drawbar. In my case, the wire is moved by a modified Atlas 2-coil sw motor, but there is no reason a Tortoise couldn’t be used instead. Take a look at this thread from a year ago: “Switchmaster versus Switch Tender turnout motors”. My longest wire is about 15", but should be usable far longer than that. The tube can be arched if necessary; the only criteria is that it approach the drawbar and sw motor straight-on. Anchor the tube in the roadbed at the switch, and also at the motor for reliability. RTV silicon works great. Whatever glue you use, be sure it is compatible with the foam rdbed.