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).
Potential overstressing of springs in the Phantom's side steering tube due to deflection allowances.
| Identifier | WestWitteringFiles\N\October1925-December1925\ Scan41 | |
| Date | 17th October 1925 | |
| R.R. 235A (100 T) (S.H. 159. 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2800 TO HS.{Lord Ernest Hives - Chair} FROM DA.{Bernard Day - Chassis Design} ORIGINAL DAL/M17.10.25. X.8450 PHANTOM - SPRINGS IN THE SIDE STEERING TUBE. We notice on F.72514. that the springs in the side steering tubes at each end are allowed a deflection of .175 from the normal position. By examining F.5007. we see that the same spring is used, and by comparing the permitted initial deflection, which appears to be .094 per spring, plus a possible amount due to the use of the washer, it does not seem possible that the two springs can follow a movement of .175 meaning that at the extreme positions of the ball the rating of the spring has fallen to half the rating in the middle, and one pad is being left behind. Besides this it seems probable that with a deflection of .175 the spring is very much overstressed. Could you examine a few side steering tubes with a view to finding what these dimensions are, namely, what is the initial deflection when the springs are loaded up normally, and then what is the maximum movement allowed in service. We have been reckoning all the time on an allowable movement of .1 . [STAMP: RECEIVED] [SIGNATURE: DA.{Bernard Day - Chassis Design}] | ||