Recently, I joined the International Society of Caricature Artists, a US-based organisation. Quite apart from the friendly reception when I first posted on their forum, it has proven to be excellent inspiration! I have already garnered various tips on using Super Sculpey, my modelling clay of choice - as well as that of most small-scale sculptors, it transpires.
So here are my Top Sculpey Tips:
First, you can use balled-up tinfoil as a core for sculptures, especially heads. Doing that would have cut down hugely on the amount of Sculpey used in, for example, the Stephen Fry piece, which is solid and weighs in at 600-plus grams (that's a lot of Sculpey for a relatively small item). Tinfoil can also be used to bulk out wire armatures, and can be shaped to a considerable degree before a 'skin' of Sculpey is overlaid and more detail is added.
Second, I can use my plastic eyes now! In an old post on my companion blog, McTodd Animates!, I described how to make fairly realistic eyes very cheaply, and with little specialist equipment. Stick such an eye in a soft Sculpey piece and bake it and, sadly, it melts...
However, the great David O'Keefe, in an interview in the ISCA magazine Exaggerated Features (no link possible, I'm afraid), gave a great tip: sculpt the eyes in place, and when baking your sculpture, place a small wad of wet cotton wool onto the eyes before placing it in the oven.
I tried it at the weekend and it works! The clay covered by the cotton wool stays soft, and can be hardened with a hairdrier (it takes a while, mind).
Finally, don't follow the baking instructions on the pack (135 celsius, IIRC, for 15 minutes per quarter-inch thickness of clay). Reduce the teperature to 80 celsius and almost double the time. Also, if you can, leave the clay in the oven when you switch it off - let it cool slowly to room temperature along with the oven, you'll pretty well completely avoid cracking that way.
Further experiments will take place...