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).
Failures of the 40/50 radiator suspension's ball end cantilever during bumping tests, with recommended design and process changes.
| Identifier | ExFiles\Box 38\2\ Scan063 | |
| Date | 10th October 1919 | |
| H.R. 235a (500 T) (S.D. 403. 26-4-17.) Bm. 2/156/13. X.3456. To R.{Sir Henry Royce} from EH. EHL/LG10.10.19. c. to CJ. c. to BN.{W.O. Bentley / Mr Barrington} c. to Da.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} BUMPING TEST FOR 40/50 RADIATOR SUSPENSION. X.3456. X.1331. Recently we have had a number of failures of the ball End Cantilever on the Radiator Suspension. We have three fail in three hours running on the bumping test, whereas we have never had a single failure on this part before. WE found that the cause of the breakage is due to the joint being tight. A new radiator had been fitted on, which, when the cup was screwed up, it clipped the ball tightly. Since we have made this joint free, we have run a further 18 hours with no trouble. The machining limits on the drawing allow the ball end and the cup to receive the ball end to be size and size. When the radiator is completed, there is a hand reamering operation in the cup portion to give the necessary clearance. We recommend that this operation is done on the tank portion before the radiator is built up so that all radiators, when they come in from Maker, are ready to fit to the chassis. We suggest also that a radius is added to the ball end lever in place of the present sharp corner. [Drawing of a lever with a ball end, with an arrow pointing to a corner labelled 'Sharp corner'] EH. | ||