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).
And a diagram detailing torsion test results on a miniature crankshaft.
| Identifier | ExFiles\Box 42\2\ Scan058 | |
| Date | 27th October 1919 | |
| Torsion Tests on Miniature Crankshaft Journals, pins, & Webs C* - C1 13 1.5 inch ton (pins clipped) 2.4 inch tons C1 - D B B1 16 3.0 inch tons web broke first 2.1 inch tons A1 - B 40 2.7 inch tons A 10° 1st fracture about 60° to Completely 2.7 inch tons D 11° to fracture completely 2.7 inch tons C - B1 9° / 15° to fracture completely 2.1 inch tons | ||