Regular readers may remember that I'm getting independent study credit to work with a local sporting goods store, Snow Mountain River, to create climbing holds out of recycled sleds.
A few weeks ago I enlisted the help of some friends and their friends to sculpt these climbing holds out of clay. We ended up with over 15 different holds, which had to dry overnight.
Next step was to mix up some plaster of Paris to slather all over the dry holds. The plaster then had to dry. Pro tip: put down aluminum foil before you sculpt and again before you plaster; it'll make removal easier.
Also, mix the first layer of plaster with more water than you think it needs. You want it to get into all the cracks and you definitely don't want air bubbles. The other layers can be a little thicker if necessary, but make sure that first one is almost watery!
The plaster will likely feel cold as it sets and the moisture evaporates out. You will also see the edges of the clay looking dark before everything is dry. Give it at least 24hrs to be sure. Then flip them over. If you can get the clay out by gentle means, go for it. I found it was stuck in there pretty well, so I tapped on a flathead screwdriver like a tiny, gentle jackhammer for hours to get all these things out. It destroyed the clay. Be very careful to chip away from the plaster as you chip, and only get small pieces at once. It's easy to chip your plaster.
Watch this space for the next part.