Hey Barry;
Ok, I think I understand where you are coming from. It can't be identified in a catalogue before '49? Were you able to come up with the missing catalogues by chance? The reason I am asking is because if there is more Slingerland info out there I would like to know where to find it and read it so I can add it to and update my personal Slingerland history I am working on.
Products commonly exist before they appear in a catalogue. (LOTS exist and NEVER make it into a catalogue.) One has to be built and photographed for it to appear in the catalogue. Catalogues commonly precede the end of the previous year, meaning a '49 catalogue is generally available in late '48. Taking into account the time it takes to produce a catalogue, photos, copy, printing, proofing, distribution, I would say products existed mid '48. We know for a fact a 20 inch mold existed at the time, although too long. Is this a guess? Yes, but a carefully considered, informed one.
The flipside to the problem of allowing the bass drum to pull the kit forward on the timeline presents another, bigger problem. The lugs went out of use 1 1/2 to 2 years before this time. That IS well documented. So either one part, the bd shell, was cut down from an existing shell, (or was a newly developed shorter shell), or, a bunch of obsolete parts, the lugs, get pulled from one drawer, and the badge, pulled from old parts drawer number two, all get used on the line on the same day a year to two years after the fact.
Occam's razor says no.
Regardless of the disagreement over dates, those will be some killer tubs.
Still jealous.