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).
Noise issues from the Phantom III steering column resonance and proposed solutions.
| Identifier | ExFiles\Box 95\1\ scan0249 | |
| Date | 13th December 1935 | |
| To BY.{R.W. Bailey - Chief Engineer} Copy to Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} RHC.{R. H. Coverley - Production Engineer} x350 E/Ev.{Ivan Evernden - coachwork}4/MN.13.12.35. F.J.H. Phantom III Steering Column Resonance. The Test Dept. have called our attention to the resonance of the Phantom III steering column which rings when tapped, causing it to act as an amplifier of any small noises. this has resulted in the following difficulties:- (1) Ticking at the column support from the dash. (2) Rattles from the steering column controls. (3) A ringing tube. It has been found that forcing a cardboard tube up the inside of the steering column deadens the tube, and it is believed this will prevent the other noises being audible. On LeC 4867 herewith we show a scheme for damping the steering column outer tube by means of split spring tube made in 26 S.W.G. mild steel, and at the moment Mx.{John H Maddocks - Chief Proving Officer} is trying this in the car in question. Should this be inadequate for the damping, the gauge can be increased, but we have chosen 26 gauge because we believe that this is the only gauge finer than 22 S.W.G. in the Factory. It has been pointed out to us that the felt anti-rattle collar on the steering controls of Phantom III is very much further down from the top of the collar than on the 25 H.P. This was necessary on the original car as there was a Bentley type of horn switch in the top of the column. Now that this switch has been superseded by the rocking button there is no necessity for this felt washer to be so far down, and LeC 4869 herewith shows a scheme for moving the washer up about an inch. Unfortunately this scheme calls for longer control tubes and cannot therefore be used until the existing stock (we believe 200 sets) has been used up. For these 200 sets it is suggested that the clearance between the top of the fitting on the top of the fixed tube and the worm tube be increased from 5/6 thou. a size to 10/12 a size. We understand that this treatment has cured the difficulty of rattles on the Phantom III car in question in the Test Dept. Ev.{Ivan Evernden - coachwork} Att: LeC.4867. LeC.4869. | ||