I noticed on of page 35 in the October issue of CTT’s article on “Retro Railroad You Can Build” that 3/4 " plywood is called out in the diagram in the upper right hand quarter of the page.
Then below, under the subtitle ‘Build a solid frame’, mention is made of “1/4-inch plywood framed with furniture quality oak”.
So which is it, 3/4-inch or 1/4-inch plywood or both - or am I missing something obvious?
Did anybody else notice this?
The Bog
I suspect that the “3/4” label on the diagram was meant to point to the 1-foot-square pads for attaching the legs and that the top was intended to be 1/4 inch plywood. Otherwise, it makes little sense to add those 1x3 joists and the 3/4-inch pads–the 3/4-inch plywood top would be solid enough by itself.
Bob,
You’re correct. The 4x8 sheet is 1/4 inch and the pads are 3/4 inch. We’re running a correction in the next issue. The pads are secured to the larger sheet using screws and carpenter’s yellow glue. It’s also important that there be a very secure bond between the foam and the 1/4 plywood, because the foam plays an important role in keeping the plywood from flexing.
Even with these precautions, the legs give a little if you bump the layout. Their mounting rings are only about 3" in diameter and the legs are pretty long. If that would be a problem in your installation, you can purchase metal legs with larger mounting plates, but I couldn’t find any like that where you can also remove the legs easily. (One of the ideas for this layout that didn’t make the story is that at holiday time you could unscrew the legs and put the layout on the floor with your tree placed on top of the layout.)
Of course no set of legs is going to provide as stable a platform as you would have if you used benchwork with diagonal bracing or mounted the layout on oak cabinets.
Thanks for reading CTT,
Terry