[Farrout1]

I used about 15 different rubber rock molds to do all this!  You can get away with a lot less by turning them in 90 degree angles and using part of the molds only. I had molds as small as few inches square all the way up to 20”x30” (1/2m x 3/4m). You mix the Hydrocal with water and a quick chemical reaction happens generating a lot of heat happens. You slap it onto the latticework and 90% of the time it sticks!!  Once you feel the heat it is set. Easy!  Just had to do that about 1 billion times to make all the rocks. I think I did count and i think it was about 150 mold applications. 

Now you have gaps between the different molds and you use what is, effectively, very fine papermache to fill the gaps. I used Sculptamold. It is AMAZING how many and big mistakes of all sorts you can make disappear at this stage because, once the paint goes on, even I could not tell where the joins where anymore. 

Here we can see one area in center of the track. I think it used 12-15 different mold applications. Note also the two sections where the road construction team had to build supporting walls from big blocks of hewn stone where the mountain simply could not support a roadway.
   
This is a focus on the main tunnel where the track goes under itself. Note the gaps and holes between the various molded rock pieces and hewn rock walls. All filled in with Sculptamold later on.
   
Look from right to left here and you can see the molded rock brick wall that is going into the platform above the tunnel and then, to left of tunnel, is the first test painted area. Never had to go back to that section as Bill did a part of it for me to train me! Amazing contrast between white plaster and painted final product.
   
A good view of the gorge and just how thin 1/2” of MDF is. Later we will add rock “bricks” to create a bridge effect here
   
Note that I never bothered to protect the painted track, the plaster dust etc just wipes off with some water and a rag.