Think differently - I can't find the link but there have been articles and sites mentioning alternate ways to mount the Tortoise. It does not have to be directly below the turnout. Using some music wire and brass tube you can make an alternate linkage that rotates rather than waggles back and forth, with the Tortoise itself way dow below the table surface.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
you could perhaps remove a section of the riser foam to make room for the tortoise, and fix the tortoise to a piece of ply around 4 x 2 inches and rebate this into the top of the foam so there is a small piece of ply to lay the track on that is level with the top of the foam riser.. it should be enough to hold all in place??
3-1/2" is a long way, even with thicker piano wire, but it should be doable. I usually use .039 diameter and once used .056 diameter for a long throw. Be aware that you might need to relocate the fulcrum above the tortoise itself.
Karl
The mind is like a parachute. It works better when it's open. www.stremy.net
I just hooked up a Tortoise with about 2-3/4" heigth of foam/plywood sub roadbed. i just used heavier steel wire, about .062 dia. Seemed to work out fine, and I think it would go higher if needed.
Good Luck,
Tom
I have a couple of tortoise powered turnouts that are 4" above the tortoise. Just use a thicker wire and make a bigger hole and it should work fine.
Dave
'there's something happening here, what it is ain't exactly clear' Modeling the Hard Knox Valley Railroad in HO scale http://photos.hardknoxvalley.com/
I have 2 inches of foam on top of 3/4 inch plywood. I simply used .039 thick wire instead of the .025 that the torti's come with. As someone said already just enlarge the hole a little and you'll be fine.. You'll also have to drill the hole in the torti for the piano wire a little larger.
Good Luck
Springfield PA