My layout is only foam of 2" on a wood frame, got a turntable, no problems.
Great news. Thank you.
Well, sure. A turntable is pretty light, even with an engine on it. I took an Atlas turntable, designed as a surface-mount accessory. I cut a round hole in my 2-inch foam subroadbed, cut a thin piece of plywood and mounted the turntable on the plywood, which I then mounted using long bolts beneath the foam. The turntable mechanism is completely below-ground. I added a turntable bridge glued to the turntable base to bring the track level up.
This was a more difficult installation than most, but I never had any structural issues even with just a foam subroadbed, no layer of wood below that.
It takes an iron man to play with a toy iron horse.
I am in the early stages of building my first model railroad. Benchwork will be extruded foam over a hollow core door. I am wondering about the feasibility of a turntable. I know I can't cut a big hole into the door, but can a turntable be installed in the foam? Has anyone done this? How thick would the foam have to be?
It's a druther, not a given, so if it can't be done, that's okay.