From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Blueprint detailing specifications for two sets of worm and gear assemblies.
| Identifier | ExFiles\Box 136\1\ scan0148 | |
| Date | 15th February 1935 | |
| MAT'L - GEAR - S.A.E. #65 BRONZE MAT'L - WORM - HY{Tom Haldenby - Plant Engineer}-TEN B-3X STEEL (FORGING) HEAT TREATED TO 35-38 ROCKWELL Left Side Drawing: 1.500 BASE DIA. 3 3/4 OUTSIDE DIA. 3.690 THROAT DIA. 2.500 CENTERS .750 ± .0005 .3750 1.150 ROOT DIA OUTSIDE DIA 2 1/8 1.910 THROAT DIA. 25/32 9/16 1/8 WORM & GEAR DATA (Left): 3 1/5 RATIO 16 TEETH IN GEAR 5 THDS IN WORM 3.590 P. DIA. OF GEAR 1.610 P. DIA OF WORM .330 WHOLE DEPTH .300 WORKING DEPTH .6660 CIRC. PITCH 33° 20' HELIX ANGLE (CENTER) RIGHT OR LEFT HAND? Right Side Drawing: 1.500 BASE DIA. 4 1/4 OUTSIDE DIA. 4.1285 THROAT DIA. 2.500 CENTERS .625 ± .0005 .3125 .8125 ROOT DIA OUTSIDE DIA 1 3/8 1.0985 THROAT DIA. 25/32 9/16 1/8 WORM & GEAR DATA (Right): 6 2/5 RATIO 32 TEETH IN GEAR 5 THDS IN WORM 4.0175 P. DIA. OF GEAR .9825 P. DIA OF WORM .140 WHOLE DEPTH .110 WORKING DEPTH .3940 CIRC. PITCH 32 1/2° HELIX ANGLE (CENTER) RIGHT OR LEFT HAND? Title Block: DWG N° P-2153-C MICHIGAN TOOL COMPANY DETROIT, MICHIGAN. 2 TO 1 RATIO - CAMSHAFT GEAR TRAIN - "CONE TYPE" GEARS - 2.500 CENTERS - ROLLS ROYCE LTD DATE 2-15-35 | ||