Very satisfying day. There really is nothing like pulling a big mold to make you feel like a champion. Of course the real proof is in the cast, but getting the mold off is a big step in the right direction. Here's how it all went down...
First, we built a wall around the cured rubber mold. In the past I found that the borders were the weak link in plaster mother molds, so the hope was that we'd fill to the wall, and create a good solid border.
Next, we covered the whole thing in fiberglass saturated in FRG-95.
In order to increase strength and rigidity, we bent a few lengths of conduit to fit along the contour of the form.
We also wrapped tie wire around the ends of the conduit to provide anchor points for eventually pulling up the mother mold.
Then we used ratchet straps to gently pull the mother mold up away from the base board. Worked like a dream. Came up in about 5 minutes, with very little prying. But before we separated all of the pieces, we built a wee wooden frame that will keep the mold more or less level as we cast it.
So that's it. A very successful and satisfying day. Many thanks to my assistant, James, who worked with me in the 95 degree heat in a closed for two days getting this thing done. Gracias.
From here, it's time to make a cast and start working the next section. Looking forward to it.