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).
Specification table detailing the particulars of four different inner springs.
| Identifier | ExFiles\Box 154\1\ scan0173 | |
| Date | 31th August 1934 guessed | |
| SHEET (2). PARTICULARS OF INNER SPRINGS. G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 81517 G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 82237 G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 82225 G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 82236 Spring Designation. A.1. B.1. C.1. D.1. Wire Dia. 0.464" 0.462" 0.487" 0.495" Mean dia. of coils. 3.00" 3.012" 2.987" 2.980" No. of coils(effective) 9 9 9 9 Normal load. 950 lbs. 971 lbs. 1163 lbs. 1243 lbs. Deflection to normal position. 3.325" 3.485" 3.310" 3.295" Free length. 10.000" 10.160" 9.985" 9.970 Max. load. 1372 lbs. 1381 lbs. 1682 lbs. 1800 lbs. Max. stress (Uncorrected) 105,000 lbs/in² 107,500 lbs/in² 110,400 lbs/in² 112,700 lbs/in² Max. deflection. 4.800" 4.96" 4.785" 4.77" Rate per inch 286 lbs. 278 lbs. 352 lbs. 378 lbs. Rate per inch at wheel 39.2 lbs. 38.2 lbs. 48.3 lbs. 52 lbs. Normally part of combination. 1000 lbs/wheel. 1100 lbs/wheel. 1200 lbs/wheel. 1250 lbs/wheel. | ||