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).
Comparison of satisfactory and unsatisfactory Firths springs based on initial camber and leaf thickness.
| Identifier | ExFiles\Box 72\3\ scan0216 | |
| Date | 13th December 1924 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. BJ. c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. to RG.{Mr Rowledge} BY.{R.W. Bailey - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} 49410 Hs{Lord Ernest Hives - Chair}3/LG13.12.24. FIRTHS SPRINGS. X2828 X4429 We give below comparisons of one of the latest 1150 lbs. Firths springs (which have given excellent results) compared with one of the previous springs which gave only fair results. SATISFACTORY. UNSATISFACTORY. Initial Thickness Initial Thickness camber. of leaf. camber. of leaf. Top leaf. 1.350 .293 .625 .310 2nd. leaf. 1.850 .258 2.00 .250 3rd. leaf. 1.750 .250 1.950 .250 4th. leaf. 1.650 .240 1.800 .250 5th. leaf. 1.500 .237 1.550 .235 6th. leaf. 1.400 .230 1.375 .230 7th. leaf. 1.125 .225 1.125 .220 8th. leaf. .900 .225 .900 .220 9th. leaf. .670 .212 .750 .215 10th. leaf. .400 .212 .425 .210 11th. leaf. .200 .200 .200 .210 Hs.{Lord Ernest Hives - Chair} | ||