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).
Page 2 of a letter from Maurice Olley regarding spring test specifications, life expectancy, and materials.
| Identifier | ExFiles\Box 170\3\ img121 | |
| Date | 15th July 1937 guessed | |
| -2- from the mounting surface at the center of the spring to the line joining the two spring eyes. (6) Load at this opening (Tolerance say +/- 20 lbs on experimental springs) (7) Test rate on rollers at this opening. (Taken as mean of up and down readings 2" each side of this position. Tolerance +/- 3 lb/in.) I know that from Eaton or Spring Perch, with flat steel spring plates and Lubropek lubrication, the friction loop will show 40 to 60 lbs. Life on experimental springs will be about 25,000 miles on the road or 200,000 7½" strokes on the cranking rig. In regular manufacture life will be double this, due to lack of hand working. Material is always S.A.E. 9260. The spring makers themselves have made the thing seem difficult and complicated, by claiming certain "riding qualities" for their particular make of spring, which of course is complete hooey, because any springs/equal true rate and equal friction "ride" alike. Kindest regards to yourself and family. Yours sincerely, Maurice Olley Maurice Olley. | ||