The water in the joint compound soaked into the plasterboard, and then migrated towards the lower section where the legs are really thin. I felt the rump area and it seemed to be dry, so I started sanding the rough spots. This giggled things a bit, and caused enough stress for the still-damp back legs to bend, just above the hoof.
I caught the problem in time and wrapped the area in paper mache strips, which I then allowed to dry overnight. No need to shoot the horse and start over.
I just got off the phone with my dad, and he had a great suggestion for next time. He said I could use rebar safely if it wrapped all the way from one leg to another over the horse’s back. I’ve always avoided using rebar because it’s so hard to bend, but he said it’s easy if you heat it up first with a small propane torch. This is definitely something I’ll try if I make another sculpture with delicate parts, like this colt’s legs. (My father knows all about rebar because he worked with concrete for so many years. Now he makes concrete garden ornaments and benches. You can see his tutorial that shows how he makes those really nice concrete leaves that you see in fancy garden magazines here.)
Anyway, here’s what I’ve done so far:
Two days ago I attached the plaster board legs, and in this photo you can see that I rounded the corners with a serrated knife. This is something that needs to be done very carefully. You don’t want to slip and slice off your thumb!
I now added joint compound. I could have been a little neater about it, but it’s kind of like frosting a cake.
I may have been able to avoid breaking the hind legs if I wrapped the plasterboard with Scotch tape, then put on on layer of paper mache to strengthen the legs before adding the joint compound. Or I could have been more patient, and I could have remembered that water flows downhill. Live and learn…
Once the ankle casts were hard and the joint compound was completely dry, I sanded the rough spots off the legs.
At this point I’m not worried about getting things “right.” There’s still a long way to go before this appaloosa colt is finished. The only thing that matters at this point is to not have anything sticking out that will need to be cut off later. Adding more material is easy – removing excess material can be done, but it’s a lot more work.
The legs have now been wrapped with the first layer of paper mache. I will use at least four more layers, using brown paper. Since paper mache is as strong as wood, I think this will be adequate.
I’m letting this layer dry with the legs up in the air because the water from the paste will soak into the layer of joint compound underneath, and it may weaken the legs again. As soon as this layer is completely solid I’ll add a few more layers of brown paper, and begin to model the head. Since the piece won’t fit into my oven, it will take a while to dry so it may be a few days before I can do another post. I’ll see you then.