subject
Clay
What is being animated?
Definition
Clay, in stop motion, means an oil-based, non-drying modelling compound -- plasticine, not ceramic clay -- sculpted, reshaped and re-sculpted between exposures so a single figure or object performs the whole shot. It has to satisfy two opposed needs at once: soft enough that an animator can push a fresh pose into it by hand every frame, and firm enough that the shape holds while the camera fires and the studio lights sit on it for hours.
Overview
The material itself is a supporting-actor problem as much as a sculptural one. A workable claymation clay is wax-and-oil based rather than water-based, which is what lets it stay permanently soft instead of drying and cracking between takes; colours are formulated to blend cleanly into new hues without going muddy, and the surface has to hold a fingerprint or tool mark crisply enough to read on camera, then erase just as cleanly under the next touch. Studios differ on how soft they want that trade-off pushed -- a general animation clay optimised for hours of reshaping is a different formulation from a sculptor's maquette clay optimised for holding fine detail under less handling.
Aardman is the industry's reference case because its supply chain became, briefly, an industry story in its own right. The studio built every production since its 1972 founding -- Wallace & Gromit, Chicken Run, Shaun the Sheep, Star Wars Visions -- on Newplast, a plasticine developed by its originator and manufactured for decades by Newclay Products at a single factory in Torquay, England. When that factory closed in 2023, Aardman bought the remaining warehouse stock outright rather than risk being left without a matched material mid-production, and kept animating on the reserve while producing Wallace & Gromit: Vengeance Most Fowl and Chicken Run: Dawn of the Nugget. The Newplast formulation was later revived under new ownership as HUE Clay, sold in the same 500g bars, oil-based and gluten/sulphur-free, described by its maker as "one of the hardest modelling materials of its type" -- firm by claymation standards, softened by warming and kneading rather than by using a naturally looser compound. The episode is a reminder that a stop-motion studio's material supply is production infrastructure, not a footnote: losing the exact clay a hero puppet library was built and colour-matched against is closer to losing a film stock than losing an art supply.
Outside the Aardman/Newplast lineage, US-market animation clays occupy a different point on the same softness trade-off. Van Aken's Plastalina and Claytoon lines are formulated to be worked very soft, which suits fast character animation and classroom/hobbyist use; Chavant's NSP is a firmer, industrial sculptor's clay more associated with maquette work, prop moulds and pattern-making than with hours of continuous re-posing on camera. None of these compounds are interchangeable without a colour and hardness re-match, which is precisely why a switch away from an established clay -- forced or chosen -- is a production decision, not a shopping decision.