White paint (except for larger, 18" floor toms which were left unfinished)
Shell date-stamping started with red ink in 1956 with comparitively large numbers and letters
1961 and 1962 stamping were still red, but with slightly smaller characters
1963 shells can be found with either red or black ink stamps
Beginning in September / October 1968; most shells were made with 3-ply Maple / Poplar / Maple
Change back to natural finish interior except for the Standard series which changed directly from white paint to granitone
The white diagonal line in this photo is the pearl covering. Up until 1969 the covering was applied to the shell while the wood was still flat, and the covering was "lapped" into the shell. This made for a less perfect round shell, but prevented problems with the finish pulling off.
Through the 1970s mahogany was occasionally still used internally or externally. (Most commonly on large floor toms and large bass drums.)
Nearly all shells began to receive interior granitone paint
Beginning in 1976, the Classic series was made with new molds and a new construction; small (6" and 8") toms were 4-ply and larger drums were 6-ply maple & poplar, with no reinforcement rings. These shells were not only stronger but less expensive to make. The interior was a clear-coated natural finish.
The 1978 Combo series was made with old 3-ply shells until they were used up; the inside was sprayed with granitone.
Standard series; Snare and tom-toms "Select 4-ply diamond wood shells", Bass drums 6-ply.
Rocker: "Select American wood veneers" 4-ply, maple interior
Rocker II: Same shells as the Rocker, sealed inside with a brownish speckled "Lud-Cote" finish.
Super Classic: 4-ply for all sizes; lighter in weight, billed as having "clean, resonant sound" (same price) (Offered as an option; the Classic shells were still catalogued, described as producing a "deep, powerful" sound)
Rocker "9-ply cross-laminated veneers with a maple inner ply"
Classic 9-ply maple approx 6mm, all maple Rocker Pro: 7-ply, Birch & Italian poplar, 7mm Rocker Elite: 5-ply, Maple inner and outer plies