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).
Wear and failure issues with spring bearings and steering components, comparing SS and Phantom models.
| Identifier | ExFiles\Box 17\3\ Scan362 | |
| Date | 30th January 1929 | |
| Hs.{Lord Ernest Hives - Chair} from DA.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} 47430 DAL/M30.1.29. SECRET. S.S. X.7770 X.7430 X.7410 X.3806 With reference to Hs{Lord Ernest Hives - Chair}2/LG25.1.29. and Hs{Lord Ernest Hives - Chair}/RmL/LG 25.1.29., we are dealing with the points mentioned where possible, and are sending you schemes, but there are one or two points on which we should like some more information. ITEM 2. FRONT SPRINGS REAR ANCHORAGE PINS NOT SUFFICIENT BEARING SURFACE. X.7410 We should like to take this in conjunction with (3) Improved lubrication to bottom of triangular lever. We know that the axle control lever on SS.{S. Smith} is shorter than Phantom, and Phantom is shorter than the correct length. We are not sure how much worse we have made SS.{S. Smith} than Phantom in the matter of loading up the spring bearing and the bearings at the bottom of the triangle. Since GWH.{George W. Hancock - Head Chateauroux} reports the latter bearings well lubricated in both cases it appears to us that the failure of which he speaks might be either a chance one, or due to the bearings being actually over-loaded and it may be necessary to increase them. The failure of the front spring rear bearing is rather persistent. It looks as though more area was wanted here, but it is already bigger than the front shackle pin as though normal load were coming on it. Could you investigate this point and send us more information? If we increase the rear spring bearing very much we shall have to alter the pressings. Much increase in the bottom bearing will probably involve a new forging, so that we are not anxious to do either of these things unless it is really necessary. ITEM 6. PENDULUM LEVER BALL END WEAR. X.7430 N.Sch.2301 was made more than 2 yrs. ago when our information about steering was not as complete as it is now and it may be that the characteristics we were trying to obtain then are not the best ones. We suggest that one of the first things to do is to reproduce on SS.{S. Smith} the best Phantom characteristics, and we propose to send you a spring to enable you to do this in the course of a day or so. It seems quite possible that it is the use of this N.Sch.2301 which is giving some people the impression of instability at speed on the SS.{S. Smith} steering. As regards GWH{George W. Hancock - Head Chateauroux}'s report of wear, though a small amount of spring load is permitted to press on the ball according to N.Sch.2301., GWH.{George W. Hancock - Head Chateauroux} reports that there was actual slack. We think this is sure to be the cause of the wear, and one thing to do would be to increase the amount of initial spring load. contd :- | ||