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).
Design specifications for rear springs for a Bentley Chassis.
| Identifier | ExFiles\Box 100\1\ scan0177 | |
| Date | 27th June 1938 | |
| 446 DESIGN FOR SPRINGS Reference Rolls-Royce letter Roy{Sir Henry Royce}/HW.1., dated 27.6.38., for 2. Rear Springs for Bentley Chassis similar to F.B.3851., but having the following characteristics:- Load................... = 1000 lbs. Width of Plates.......... = 2". Span................... = 50.0". Loaded Camber............ = Nil. i.e.Spring flat. Free Camber.............. = 7.0". Deflection due to Load. = 7.0". positive. Main Plate thickness. = .26". For particulars of design see table below. ================================================================= Plate | Thickness | Length | Ex. Dist. | Remarks Nos. | Inches. | Inches | Inches. | ================================================================= 1. | .26 | 50 + 2 eyes. | Nil | Rolled eyes to be the same as FB.3851., but with riveted lubricators. M.P.ground, other plates concave buffed. All plates to be polished & plated. Clip positions:- Front end - 9.3/4" & 19.0". Rear end - 11.0" & 19.3/4". ex Centre bolt. 2. | .25 | 48.6. | .7. | 3.x | .24 | 42.3/8. | 9/16. | 4. | .23 | 36.0. | 1/2. | 5. | .23 | 30.0. | 1/2. | 6.x | .22 | 24.1/8. | 9/16. | 7. | .22 | 17.1/2. | 3/8. | 8. | .21 | 11.0. | 1/4. | ----------------------------------------------------------------- TOTAL.| 1.86. | ---- | ---- | --------- ================================================================= NOTE. Range of stress to the Loaded position = 37.8 Tons per Sq. inch. " " " " " Max. Bump " = 59.5 Tons per Sq. inch. HWs! T.F & J.B.Ltd. 29.6.38. Filed to TB I . 30.6.38 | ||