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).
The testing and implementation of new, lightened D.W.S. Jacks for 40/50 HP and 20/25 HP models.
| Identifier | ExFiles\Box 139\2\ scan0158 | |
| Date | 23th November 1934 | |
| x3117 To Hy.{Tom Haldenby - Plant Engineer} c. to Ha/Fm. c. to E.{Mr Elliott - Chief Engineer} c. to NOr. c. to ERt. c. to Roy.{Sir Henry Royce} D.W.S. Jacks. We have tested 40/50 HP. and 20/25 HP. lightened D.W.S. Jacks and report as follows :- Although these Jacks have not done 10,000 miles, they have been severely tested without ill effect and we recommend that they are fitted on future series, for the following reasons :- (1) They are lighter than present standard Ph.II Jacks, weighing 48 lbs. 8 ozs. against present 57 lbs. 6 ozs. - a saving of approximately 15%. 20/25 Jacks weigh 33 lbs. 4 ozs. against present 37 lbs. 12 ozs. - a saving of approximately 11.8%. (2) The main operating shafts are shorter and have now a right and left hand thread giving a much easier action. (3) They have an increased lift of approximately 1". Generally, the new Jacks are a better and neater proposition, the price remains the same. However, there will be a slight increase in price for a special front bracket which we have asked the D.W.S. Co. to supply for the 20/25. This bracket is similar to the present 40/50 HP. and gives more ground clearance by holding the Jack in parallel with the front axle beam and so obstructing from view. With regard to the 40/50 HP. rear Jacks, the top surface of the Jack housing is now lipped, this prevents our present bracket flange from fitting squarely on this surface and in order to save altering the casting it will be necessary for us to make alum. packing pieces as shown on the rough sketch attached. | ||