The concept for the percussion part of things is pretty much an alien plant that plays itself. It has five pods as the "drums" that its stems will beat. I plan on rigging up LEDs to make each pod glow whenever they are struck. We'll see how that works out. Here's my initial drawing:
Using Super Sculpey Firm clay, I sculpted a single pod and stem that will be duplicated in the casting process:
After smoothing out some of the features, it was time to make molds of both the pod and the stem. I poured an RTV urethane rubber over the clay sculpts in two parts to create the molds.
After the molds had cured it took me a couple of months to get to casting the pieces. I'm a slacker. Sue me. I used an RTV tin-cure silicone that I had on hand to cast the first pod, but realized it wasn't going to work because it ended up being too stiff and opaque. I needed the pods to be softer so I could animate a "squash" when they were hit. Also, I wanted them to have some transparency so that I could light them from the inside to get the glow effect that I mentioned earlier. A bit of research later, I ended up getting some Dragon Skin platinum-cure silicone from Smooth-On. It had the softness and transparency I was after and I found it much easier to work with. Really cool stuff and cures in a quarter of the time. Blue pigment was added to get the base color that I wanted.
To cast the stems, I used the opaque tin-cure silicone since there will be aluminum armature wires down the middle of them that I don't want to be visible. Part B of the silicone mix is already blue so I didn't give it any pigment.
Here's all five of the pods and three stems. I was planning on having five stems, but it's getting a little crowded in the space and animating is gonna be tricky enough as it is. I may add a fourth or fifth since I'm into the challenge, but I'm definitely no Harryhausen.
That's it for now. Part 2 will be all about painting these bad boys.