Tests conducted to eliminate flapping and pedal oscillation caused by side spare wheel carriers.
| Identifier | ExFiles\Box 13\5\ Spare05-page112 | |
| Date | 20th October 1931 | |
| x7600. To Da. {Bernard Day - Chassis Design} from Hs {Lord Ernest Hives - Chair} /Les. " EV. {Ivan Evernden - coachwork} c. to By. {R.W. Bailey - Chief Engineer} Hs {Lord Ernest Hives - Chair} /Les.S/KT.20.10.31. SIDE SPARE WHEEL CARRIERS P.II. On the present cars the side spare wheel carriers acquire their rigidity from the rear engine feet. Therefore with diamond engine mounting the side spare wheels flap badly and cause the pedals to oscillate. We have therefore carried out tests with the Bumper chassis in order to eliminate this fault by supports to the dashboard. N.S.3322. This was originally intended for the 25 HP. where the connecting strip is parallel to the dashboard, under instructions from W.W. this was adopted for P.II Scheme 1532. here the connecting strip D.73398 is not parallel to the dash. By. {R.W. Bailey - Chief Engineer} sent a copy of this scheme to W.W. to point out this fault. On the Bumper the O.S. wheel was satisfactory, but the N.S. not quite so good. The running was now continued at the maximum jellying speed. The following parts failed :- O.S. Bracket F.58153 (as sent to W.W.) after 8.30 hrs. O.S. Connecting Strip (as sent to W.W) after 3.30 hrs. O.S. (similar to previous) after 4.30 hrs. N.S. 1/4" bolts holding the connecting strip to the bracket after 35 hrs. N.S. Bracket F.58153 cracked where the bolt furthest from the centre chassis goes through, after 40.30 hrs. From the above list it might appear that the N.S. was satisfactory and something faulty with the O.S. As stated previously the N.S. wheel flapped more than the O.S. which is possibly due to the connection of the frame to the dash by the steering column. On the O.S. the bracket F.58153 was bending the dash and in consequence preventing the initial blow by the bracket pivoting at its connection to the strip D.73398. Both 1/4" nuts were continually becoming loose until they were tightened whilst the pump was in motion. Then eventually the head came off the 1/4 bolt. We consider such brackets as N.S.3322, and D.73306 the bracket as designed at Derby for the use with the removal of rear engine feet, to be unsatisfactory from | ||
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).