Dimensions Of Tortoise Switch Motor

mark_newton wrote in news: snipped-for-privacy@optusnet.com.au:

This brings up a related question that has been in the back of my mind. I will be using 2 thicknesses of 2" extruded styro panels on top of a 1/2" plywood table as the base of my scenery. What is the best way to use under-the-table switch motors on this kind of base?

I thought about cutting 1/8" plywood bases for the turnouts themselves and mortising the bases into the styro with whatever extra cutout was needed for the switch motor. This way, as long as the turnout was not soldered into the rest of the track, you could lift the whole thing out for service or troubleshooting.

Or am I trying to make this too difficult?

At the club, we settled on a 1/2" plywood block 3-3/4" square. We made a jig for pre-drilling the block so that every Tortoise would fit exactly the same way on each block. We soldered wires from the Tortoise to a molex 8-wire screw down connector. All the under layout wires connect to the other side of the molex connector. Every control rod that goes up through the layout surface (3/4" plywood pus 1/2" homasote, solid spline sub-roadbed ... whatever) is fashioned to have the same "swing" distance. Any prefabbed switch machine can be used to replace any other switch machine since it will screw into the same holes as the previous switch machine (mounted on the uniform 1/2" block). In a few cases we used RC aircraft rod-in-tube (can't remember the correct name) to get from a sensible place to mount the switch machine to some bizzare underlayout location to drive the switch. We replaced the Tortoise wire with a slightly thicker and longer piece of piano wire.

I'd go for something heavier at least 1/4" but, 1/2" would be better Attach directly to the underside of the 1/2" plywood layout base.

Sounds like it to me.

The Tortoise is 3 1/4" high. However, I would leave a minimum of an additional 1" to 2" clearance to access wiring connections at the bottom of the machine.

snipped-for-privacy@pimin.rockhead.com (Paul Newhouse) wrote in news: snipped-for-privacy@comcast.com:

Maybe I didn't describe this well enough. The track and turnouts will be separated by 4" of styrofoam from the underlying 1/2" plywood. That 4" vertical seemed like a long distance between the turnout and its actuator. I was talking about small piece of plywood to mount the actual turnouts on that would be inlayed into the top surface of the styro, with the actuator mounted under the inlaid piece rather than the actual table top.

The actual table is inspired by Scheicher's "monocoque" construction as described in the 3rd edition of his "Model Railroad Handbook." I decided against the full monocoque method since I already had one 4x8 table with a 1/2 plywood top. I am building a second, identical table, arranging them in an L shape and putting the 4" of styro on top to be able to carve away negative elevation terrain and build up positive elevation with more layers of styro. All trackage will be at relative 0 elevation, i.e. 4" above the plywood. That idea came from Gary Courtemanche's spectacular Blood, Sweat & Tears railroad.

Huge plus and minus swings of terrain elevation, but all the track is dead level.

Shouldn't be a problem. The wire that moves the turnout will run doen the 4-1/2" and it should be enclosed in a tube. We use brass wire enclose din a brass tube (I forget the dimensions right off hand). The tube should fit snuggly in the hole that penetrates the plywood and should fill the hole in the 1/2" plywood, and run up to just under the ties.

I would thinkt he foam would be severely compromised with the method you are describing.

Paul

Why compromised? Just a 1/4" recess in the top of 4 inches of foam and a 2 inch square hole where the tortoise goes through. It should not be any problem, but if you want to lift them for maintenance it will be difficult to disguise the joint lines in the roadbed and you will need to arrange for all 6 joiners to slide back. I think I would prefer to mount the tortoises underneath. Keith Make friends in the hobby. Visit Garratt photos for the big steam lovers.

The Tortoise is how much of that 3-3/4" of remaining foam? Pulling down on that 1/4" recess, which is how square?

A 3/32" or so hole for the rod & tube seems like a lot simpler solution to me.

Paul

Excellent Lynn, thanks very much!

All the best,

Mark.