Because of this the rock work I am doing on the ravine walls is taking forever to dry! The picture below is the wood and hardware cloth frame covered with mache and wood putty. I've just added a section of styrofoam board to build up the rock face.
This is the styrofoam rock face before I added my mache/wood putty mixture.
This is the rock face about 75% finished. I just have to refine the cave entrance a bit.