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).
Letter to Vandervell Products Ltd. concerning modifications to crankpin and connecting rod dimensions.
Identifier | ExFiles\Box 115\2\ scan0528 | |
Date | 9th February 1940 | |
File Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}1/BA. 9th., February, 1940. Messrs. Vandervell Products Ltd. Western Avenue, Park Royal. W.3. Attention of Mr. G.A.Vandervell. Dear Sir, L. 1020 Confirming our telephone conversation of 7th. February, and referring to your letter ref: GAV/LT. dated 1st. February. It now appears, that in order to accommodate your standard thickness of material, it does not matter whether we increase the pin diameter of the crankshaft, or decrease the bore of the connecting rod. This being so, we prefer to modify the conn.rod, as this will be the more convenient way of obtaining further figures of merit on existing engines. We now have two crankpin sizes, which we refer to as 2.0" and 1.75". Your latest drawing for the 2.00" pin is L.1134. but you have altered the crankpin from 1.9985/1.999 to 2.0025/2.003. Your latest drawing for the 1.75" pin is L.1164 and you have altered this crankpin from 1.7485/1.749 to 1.7525/1.753. We shall be pleased if you will review both the above drawings, and in view of your later information, revert to the original crankpin dimensions in both cases, and accommodate your .071 thick material by altering the rods to suit. ( continued ) | ||