NEW PRODUCT TIP: So you say you wanna build up an armature with something so light weight it'll float?...Sculpy Ultralight ran across this whilst surfing yesterday, thought you should know about it.
"Sculpey UltraLight is an extremely versatile clay that allows you to do things that could never be done before with clay. It turns hard as a rock when baked so it won't break or crack, even in large pieces. When rolled thin and baked, the clay remains flexible. When used as a base for armatures or large beads, shape Sculpey UltraLight to desired form and bake. Remove from oven and allow to cool. Cover Sculpey UltraLight base with Sculpey III or Premo clay and bake again. Sculpey III and Premo clay sill chemically bond to the Sculpey UltraLight base when baked and make the final piece strong and crack resistant. Once cool, baked pieces can be polished, sanded, drilled, carved and painted the 100% acrylic paints.
Bake in an oven-proof glass or metal surface at 130 C(275 F) for 15 minutes per 6mm (1/4") thickness. DO NOT USE MICROWAVE OVEN. DO NOT exceed the above temperature or recommended baking time. Remove from oven and allow to cool. Supervise children during baking."