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).
Comparative efficiency and user effort of various jacking systems.
| Identifier | ExFiles\Box 139\2\ scan0058 | |
| Date | 16th March 1934 | |
| 3117 BWG{J. C. Bowring} Cx{Major Len W. Cox - Advertising Manager}2/KW16.3.34. S/W. Hs.{Lord Ernest Hives - Chair} c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. " E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. " DY.{F R Danby} D.W.S.Jacks. Sessions # In reply to Hs{Lord Ernest Hives - Chair}6/MJ12.3.34. I quite agree with you in all you say about the comparative efficiency of the Dunlop and D.W.S. jacks. That point, of course, was not in question when I wrote to you. My chief concern was that the effort required to use the D.W.S. was in some cases more than a customer could manage, and this naturally prompts us to ask if it is possible for the makers to be persuaded to try and reduce this effort required by decreasing the friction that has to be overcome. The only jack I know of that might be better from the customer's point of view is Smith's hydraulic Jackall but there may be much stronger objections from our point of view against this type of jack than there are against the D.W.S. The Autocar last week had an article on "Easy Jacking Systems" in which the D.W.S. and the Smith's Hydraulic Jackall system figure very largely. Certainly, reading the article - which I attach in case you have not it by you - the customers would be very much impressed with the ease of operation of the hydraulic system, but this may have many serious objections from our point of view. I still feel, therefore, it might be worth while drawing the attention of Messrs Sessions to the fact that certain of our owners are physically unable to raise their car, and for that reason we are naturally seeking an improvement in that particular respect if such is possible. There is of course no question of our reverting to the old system of the Dunlop screw jack. Cx.{Major Len W. Cox - Advertising Manager} Enc. | ||