I have a 90' one and put just a little caulk under the edge to make sue it didn't move as hole was not perfect as another turntable used to be there and I needed to move the hole slightly.
I have the Walthers 130' non-DCC version of the turntable. It just sits on the layout without any screws to hold it down. Been like that for 13 years without a problem.
Rich
Alton Junction
Thanks for the good advice. I think I'll go with just letting gravity handle it for now. When the roads are no longer icy I may eventually detour over to FastenAll to have them do the 'screw identification' and get longer screws.
Grinnell
I have one of the early 'built-up' Walthers indexed 90' model offered in 2006. I just placed it into its hole, but I did secure both the lead rails and the three pairs of radial bay track rails to its lip using CA or epoxy...forget which...and that seemed to keep if firmly in place. For my installation, I removed at least one tie at the rail ends and had to grind two shallow grooves to take the Code 100 nickel-silver rails so that their bearing surface height matched the smaller code on the bridge.
My Walthers 90' unit is just dropped-in and not secured. It hasn't moved. The tabletop is ½" Homasote on ½" plywood.
Dante
I don't have one but I did have a 90' Heljan which I did not fasten to the benchwork. JIL2000 has a you tube vid on installation of the Wathers TT but he doesn't mention screwing it down either.
If you felt the need, a couple dollops of silicon caulk ought to do it.
Henry
COB Potomac & Northern
Shenandoah Valley
The Walthers turntable seems to be designed for a 1/2 inch thick benchwork top; the screws are too short for my 3/4 inch plywood. The pit doesn't rotate, so it looks like I could rely on gravity to keep it in place (until I glue the tracks down). What do you recommend? If you used screws, what size (looks bigger than a #2 and self tapping?)?