A lot of bracing. Crosswise bracing too, you don't want the plywood to twist. Plywood might seem rigid, but it's not intended to span long distances unsupported - there's a reason most of it is installed on 16" on center wall studs and joists.
If in doubt, over-build.
Do you need a 40" opening? Most doors are 30-36". A narrower opening is easier to build, needs less bracing and can use fewer/lighter hinges. But see comment above about over-building.
Genesee Terminal, freelanced HO in Upstate NY ...hosting Loon Bay Transit Authority and CSX Intermodal. Interchange with CSX (CR)(NYC).
CP/D&H, N scale, somewhere on the Canadian Shield
Thank you for the replies.
It's 3/4" plywood and will use a circular saw.
Is one strap under each edge sufficient?
Thank you,
Richard
How thick is the plywood?
Just generally, I would use the bracing beneath the wood. That's a fairly long piece of wood at 40 inches, and it could begin to sag under its own weight alone.
1x2 is cheap. Putting a piece along the front edge would double as fascia and let you have unseen wiring beneath the liftoff for track feeders, signals and such. Better safe than sorry..
It takes an iron man to play with a toy iron horse.
cowmanWhat is the best blade to cut the plywood with?
Are you going to cut by hand, or use a power tool?
Getting started on the around the room shelf for my new layout. Finally!! The room is in a dry basement with only natural humidity.
The room is 7x14 with one window (above layout). The door has been reversed, so that it swings out. Since I want to be able to have continuous running. I am planning a tip up gate, as there is no place outside the door to store a lift out and very limited space in the room to maneuver one. A club that sets up at some of the local shows has one I am trying to copy.
I will be using most of a 2x4 sheet of birch plywood as the surface for the 40" span. The sheet will be sealed with paint or other sealent. Do I need to run a 1x2 stringer or two, length wise under the plywood to prevent sagging? Do I need any crossways?
I plan to take about 1" off the width of the plywood so that it does not contact the wall. What is the best blade to cut the plywood with? Never have worked with birch plywood before.
The surface of the layout will be 2x8 sheets of 2" extruded foam cut to needed lengths. Elevations will be made from extruded foam picked up at construction sites. FREE. (Asked first)
Need to learn how to post photos once I make some progress. Have two sons that should be able to pound it into my head, but computers and I have a wall between us which I frequently run amock of.
Thanks for your time.
Have fun,