fabrication
Cast clay over a floating armature: the Gumby method
Armature / Clay / Claymation: Clokey, Vinton, and the Road to Laika
Definition
A cast-clay puppet-building method, distinct from the sculpt-clay-onto-a-rigid-skeleton approach used on most later ball-and-socket puppets: modelling clay is poured, softened by heat, into a stone or silicone mould with a "floating" wire armature suspended inside it, so the figure comes out of the mould already formed around its own internal skeleton rather than being hand-built up in layers over an exposed one. Art Clokey's Gumby (1955) is the technique's defining example and the reason it is still informally called the Gumby method.
Overview
Most stop-motion puppets today are built by fixing a rigid skeleton first -- a wire or ball-and-socket armature (see Armature) -- and then sculpting or moulding a skin of clay, silicone or foam latex onto and around it piece by piece. The technique behind Gumby inverts that order: a batch of prepared clay is poured, while still softened by heat, into a stone or silicone mould that already has a wire skeleton -- a "floating armature," not fixed to a base or jig -- suspended inside the cavity. The clay sets around the wire in one pour, so the figure comes out of the mould as a single cast object with its skeleton already sealed inside, rather than a skin built up afterward over an exposed one.
Art Clokey developed the character out of Gumbasia (1953), a USC student film built on the "kinesthetic film" theory of his teacher Slavko Vorkapic, applying it to lumps of clay rather than drawings. Producer Sam Engel saw a private screening and pushed Clokey to build a children's character and stories around the technique; NBC's Tom Sarnoff approved a pilot, and The Gumby Show debuted on Saturday mornings in 1956/57 -- establishing the cast-clay method as a way to keep one character consistent across an entire television series, not just a one-off short. Clokey's own design choices for the figure -- a bottom-heavy stance so it could stand unaided for photography, a slanted head modelled on his father's haircut, and a green colour Clokey described as racially neutral -- were built into the mould itself, not painted or dressed on afterward.
Puppet maker Nicole LaPointe-McKay, who has built Gumby figures at Clokey Productions, describes the process concretely: the clay -- Van Aken Plastalina, mixed to the studio's own colour and consistency recipe -- is boiled in a double boiler until the batch is uniform, then chilled to firm it before pouring. The prepared silicone or stone mould, with the floating wire armature already positioned inside it, receives the poured clay; once set, the cast figure is pulled from the mould, its seams trimmed and any bubble marks patched, then given an oil massage to smooth the surface before facial features are added against a faceplate guide. Because studio lighting heat softens and degrades a cast-clay puppet over a shoot, productions keep many duplicate figures on hand for consistency -- LaPointe-McKay puts the figure as high as twenty Gumby puppets for a single minute of finished animation.
Clokey Productions reused the same cast-clay method for Davey and Goliath (1961-1975), its second series, made first for the United Lutheran Church in America and later the Lutheran Church in America -- evidence the technique scaled to a second, unrelated character rather than being a one-off trick built for Gumby alone. The cast-clay, floating-armature method remains distinct from the skin-over-skeleton fabrication used on modern ball-and-socket puppets (see Puppet, Armature, Skin materials): a difference in build order, not just material, that separates Gumby's lineage from the Corpse Bride, Coraline and Wildwood puppet-fabrication tradition documented elsewhere in this wiki (see Mechanical puppet).
Workflow
- Mix a fresh batch of modelling clay (Van Aken Plastalina, per the studio's own colour and consistency recipe).
- Boil the clay in a double boiler until its colour and texture are fully uniform.
- Chill the mixed clay to firm it before moulding.
- Prepare the stone or silicone mould with the figure's floating wire armature suspended inside it as the skeleton.
- Pour the prepared clay into the mould around the armature and let it set.
- Remove the cast figure from the mould; trim seams and patch any bubble marks.
- Give the figure an oil massage to smooth its surface, then add facial features against a faceplate guide.
- Retire and replace the puppet as studio-light heat softens or degrades the clay -- a single minute of finished animation can need twenty duplicate figures or more.