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 a Buick Jack against a similar type by Dunlop.
| Identifier | ExFiles\Box 139\2\ scan0235 | |
| Date | 11th April 1935 | |
| To Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} +3117 Hs{Lord Ernest Hives - Chair}/Bwg.{J. C. Bowring}1/KW.11.4.35. Comparison of Buick Jack against similer type by Dunlop. The Dunlop Jack tightened on the threads almost to a seizing point due to distortion after having raised and lowered a Bentley car four times. Both makes of Jack incorporate the same dia. square threaded shafts, but Brinell figures show that Buicks have used a tougher steel than Dunlops, the figures being :- Buick 255 Dunlop 196 The Dunlop Jack is definitely a better finished job throughout; it has not the excessive play in the threads that the Buick has. Steel gears are used by Buick, whereas a Phosphor Bronze bevel gear and steel pinion are used on the Dunlop. At present the Dunlop Jack weighs 4 lbs. 2½ ozs. against 3 lbs. 6 ozs. of the Buick, but we understand that eventually the Dunlop casing will be of alum. Hs{Lord Ernest Hives - Chair}/Bwg.{J. C. Bowring} | ||