Unless I'm mistaken, the UNI prefix stands for "one". That is to say ... it is the "one" mold. Put the wood into the mold and out comes a drum as if it were formed from a single ply. The layers of individual wood plies are 'molded' together into a 'uni' (one) or single solid ply. UNI-MOLD.

Prior to using the "uni-mold" construction technique Slingerland would dry bend a flat piece of laminated plywood. Uni-molding put individual plys of wood in a mold, adding glue and then another ply of wood, etc. The mold is heated and an air bladder inserted applying pressure. Slingerland started using this method around 1963.

FYI

O.K., but in the 73' catalog the sound king toms and the stage band toms both say uni-mold they were not solid shells. Also the Buddy Rich 4 x 14 snare says uni-mold and I've researched this and as far as I know there were no solid 4 x 14's made. Uni-mold is also described on the Radio King which we all know is a solid shell. So is the "uni-mold" term a type-o in the catalog?

Let's try this again ...

Unless I'm mistaken, the UNI prefix stands for "one". That is to say ... it is the "one" mold. Put the wood into the mold and out comes a drum as if it were formed from a single ply. The layers of individual wood plies are 'molded' together into a 'uni' (one) or single solid ply. UNI-MOLD.

To elaborate on your two statements ...

The Radio King was not always a solid shell. There are plenty of 3 ply snares out there with the Radio King name. There's also single ply snares that do not hold that name. The magic and mystery that is Bud Slingerland.

Uni-mold drums ALWAYS have multi ply shells that have been formed in the Uni-mold forms. In the Uni-mold forms, the plies are glued together, and pushed in to roundness conformation against the inside surfaces of the molds by inflatable bladders. There are NO SINGLE PLY Uni-mold shells. That would be an oxymoron.

E X A C T L Y ... Thank you for the additive assist.