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).
Instructions for altering the dimensions of a 20/25 HP crankshaft and related components for testing.
| Identifier | ExFiles\Box 103\3\ scan0109 | |
| Date | 2nd October 1931 | |
| E.{Mr Elliott - Chief Engineer} Dept. (crossed out) c. RHO (crossed out) c. HS{Lord Ernest Hives - Chair}/GRY.{Shadwell Grylls} X5010. BY/SS{S. Smith}2/J 2.10.31. [STAMP: RECEIVED OCT] 20/25 HP. CRANKSHAFT. ------------------- As we are anxious to test as soon as possible balanced crankshafts with 2.250"dia. journals and 2.000" dia. crankpins, Mr.Bailey has released the "hold-up" on the forgings for producing crankshaft E.56885. Will you therefore please alter the diameter of the journals from 2.1245" to 2.2495", and the width of the webs from 3.250" to 3.350" as both these dimensions can be obtained from the forgings. The bore of the crankpins should be increased from 1.000" to 1.250", and provision made for locking the balance weight studs. In order to machine the increased diameter of the crankpin bores it will be necessary to arrange the fixing of the balance weights as shewn on LeC.2952. Details should also be prepared as soon as possible for the main bearings and caps to suit the 2.250" journals as shewn on LeC.2937. We should instruct the Experimental Dept. to machine the front of the shaft as shewn on their drawing EX.6839 so that extension pieces may be fitted to suit any of the three types of spring drive. BY/SS{S. Smith} | ||