Work continues on the terrain boards...
I decided to make the boards 18x36" instead of 24x48" as this allowed me to both transport the boards easier and clean up the edges of the 4x8' sheet once cut - it was getting beat up in the garage! Also the smaller size didn't require any center support. I added 2" strips of 3/4" plywood to the edges and joined everything with 3/4" brads and carpenders glue. The boards are super sturdy and have zero warp. I think the 24x48 boards would have been better for the larger games but I can see making a river board, a major hill board and the like so there will eventually be a bunch more boards to make big maps.
I then covered the surface with my mixture of tile grout, sand, PVA, brown house paint and a bit of water. I found this was very durable when dry. I used a roller to apply a thin coat of the mixture to the entire board. Once dry (1 day) I added a dark brown wash made with ink and water. Once this dried (again 1 day) I drybrushed all the boards with the original brown paint. I created a few dusty areas by working in extra paint (see top photo).
The texture is pretty rough but as most of this will be under the flocking, I am not too worried. One issue with terrain I struggle with is that the better looking your terrain is, the harder it is to play on. As well, when adding modular terrain on top, you want the base surface to be flat - VERY flat. For that reason, I will probably NOT add grass tufts or rock piles to these boards but instead will add these features to the modular pieces.