Silicone & Clay

I played with more clay to recreate the missing half of the clay former I'd made.

I had reasonable success and covered the whole thing in resin for stability. I then smeared ordinary caulking silicone all over it, topping it off with some liquid silicone, but doubling the recommended volume of catalyst. It set perfectly, but was still not the perfect shape and a bit on the rough side because of the smeared caulking silicone, which can't be rectified once dried, I believe. Rough as the proverbial badger's bum and not worth keeping.

Went back to the liquid silicone filled clay vase I'd molded from the original lampshade and waited till Wednesday before cracking the silicone out of its clay vase, as it just wouldn't cross-link fast enough.

Perfection, although it was still a bit wobbly inside (inserting a skewer into the top determined it was still wet inside), but that will improve over the next few days.

I have enough FIMO clay left to make another impression of the original lampshade, but not enough liquid silicone to fill it, so have ordered some more. That would enable me to make 2 lampshades at a time. On 2nd thoughts, I'm probably better off sinking the silicone former into a tub of resin to create an impression and then fill the resin impression with liquid silicone to create another former.

The next objective was to make a stand for it that's at least 30cm high. I used a carboard picture roll with one stopper end resined into a coaster disk to make a platform and the other end resined into a Tupperware box to provide a stable base.

I have learned something in my resin experiments - it you're encasing an object in resin it's best if you ensure it's not something that contains miniscule crevices that trap air. While it will appear quite clear when you pour the resin over the object, the catalysing reaction increases the temperature of the resin considerably, resulting in the trapped air to bubble out of the covered object as it resin is drying, leaving a snake of trapped bubbles in the matrix. Some of these can be drilled out and refilled with a plastic pipette, but not all of them. Even if you refil the drill holes, a slightly different mix of resin and catalyst can cause refractive differences.