Finished the backdrop this morning. had couple setbacks during the week with repeat joint cracking.
Started adding the first two layers of ceiling tile (approx 1 1/8" or 15 scale feet thick) to form the base or 0" elevation, to allow for any creeks and such. The layout will have two levels, to be added (where needed) by three more layers of ceiling tiles (approx 1 11/16" or 22.5' scale feet thick) this plus road bed should allow for track clearance.
First layer I screw on, so to make it easy to remove if needed and allows for reuse of benchwork. I am also reusing some tiles from my dismantle HO Layout.
Here my preferred choice of adhesive is Loctite Power Grab, heavy duty was used for the backdrop had some left over so I going to use it too.
I apply a bead around the edges and one down center, then slightly spread the bead out. I do this as the Power Grab only gives you a few seconds to adjust the tile, so I get a smooth and level tile.
Here the far end of the layout done with both layer
The drywall saw does not give as smooth of a edge as does the rotozip
But the rotozip creates a lot of dust in the air, possible if you have a helper with a shop vac this could be minimized, but the rotozip does a quick job of trimming.
Here were I ended today, tomorrow the other side.