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).
Technical memo detailing road test findings and issues with damper loading, control arms, and brakes.
| Identifier | ExFiles\Box 1\4\ B001_X 100a-page090 | |
| Date | 1st December 1932 | |
| X405 By - Can we easily increase the ball arear of the axle control slightly? Rm{William Robotham - Chief Engineer} To Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} From G.W.H. Hotel de France, Chateauroux, FRANCE. 2.PER.II. 1.12.32. [Handwritten notes on left margin:] Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer} We have increased the ball P.L. P/idea Ref 3/4 20/25 HP only e/c ? Re learning returns unt GWH{George W. Hancock - Head Chateauroux}? With the further reduction of the damper loading to 70 lbs., the car rides very well at low speeds over cobble stones etc. but for medium and high speeds the pitching is unpleasant in the rear seats, and the car does not hold the road so well. We have therefore come to the conclusion that for the best high speed touring condition, 90 lbs is required, and for town work 70 lbs. FRONT CONTROL ARMS. The contacts for the front control arms have been scaled down too much. We examined them for the fault you mentioned, i.e. bolt tightening up the spring lead contact - but find this is quite O.K. It is the rear contact that gives all the trouble. On both side, N.S. and O.S., these contacts are now practically useless. If any more wear takes place we shall not be able to take it up. The oil supply to these contacts is too small. There is a No.1 bijur fitted which is too uncertain for these important parts, but at the same time, we have had failure of oil supply many times on the Phantom and 25 HP, to this part without the disasterous results we are getting. These have only to be short of oil for a day and the ball has hammered right into the contact. This again occurred during yesterday's run, the oil apparently having become air trapped. When one considers the amount of work the control arms have to do, the area of contact is ridiculous. This was the cause of the cross steering tube fouling and hitting the oil pump. It also affects the lean of pivots, steering, etc. BRAKES. We have not been able as yet, to obtain good braking. It is altogether too spongy. We have made the rear shoes solid but it made no difference to sponginess. We have had to lift the foot brake pedal too high, so as not to come on to the boards, but you can press as hard as it is possible on the foot pedal without any further results. We definitely say that the toggle shafts wind up and the equalizing shafts bind. ROAD SPRINGS. We shall have to dismantle the O.S. front spring to [Handwritten initials bottom left:] JWH. | ||