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).
Issues of scuttle jellying and bonnet rattles, comparing total and semi-isolation methods.
| Identifier | WestWitteringFiles\S\March1928-May1928\ Scan031 | |
| Date | 12th March 1928 | |
| To R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Rp. c. to B.J. Wor.{Arthur Wormald - General Works Manager} c. to DA.{Bernard Day - Chassis Design} BY.{R.W. Bailey - Chief Engineer} c. to Hm.{Capt. W. Hallam - Head Repairs} CWB. c. to Sg.{Arthur F. Sidgreaves - MD} C. c. to Ps. Pt. ORIGINAL. Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/LG12.3.28. SEMI ISOLATION. V46/3 X7500 We are strongly opposed to total isolation. In our experience it produces scuttle jellying and bonnet rattles. The most recent example of this was on 10-G3. The scuttle moved about so much that every pipe between the instrument board and the dash was broken except the oil gauge, thus throwing out of action the screen wiper, distance petrol gauge etc. The scuttle was semi-isolated and the car ran 10,000 miles without further trouble. Trials car 7-LC was another example and gave a most unfavourable impression when we took it over to France. The case of 15-EX is rather different because the WW. scuttle damper prevented jellying. However the bonnet rattles on this car were most objectionable, even when the column was rigidly supported by stays, until we adopted semi-isolation. As we see it, the scuttle is rigid longitudinally but flabby transversally, the dash immensely strong transversally but weak fore and aft. The scuttle damper deals with the body movement reasonably effectively, but the dash still deflects being pulled about by the radiator causing irritating bonnet and control rattles. The whole arrangement does not seem so satisfactory contd :- | ||