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).
Failure of front axle pivots and proposing modifications to the design and materials to improve strength.
| Identifier | ExFiles\Box 2\12\ B002_X168-page014 | |
| Date | 27th February 1913 guessed | |
| R3/B1313. [Handwritten:] Mr Wormald From F.H.R. Copies sent to: Mr Johnson Mr Wormald Mr Spinney Mr Nadin? [Typed:] Re 2 front axle pivots which have been sent to me. There is no doubt but that these have been broken by torsion, as suggested, I think, by Mr. Spinney. This is a very important matter and every car which comes in for repairs should be carefully examined for any flaws commencing at the bottom flange. If many are found something must be done to stop the fault. I have suggested that the front wheels should be subjected to tupp bumping tests - this is just to ascertain whether the pivots or the steering gear are the weaker. I should like the following alterations to be made and I think that these modifications would considerably reduce the stresses on the parts due to the sudden blow in front of the road wheels. This will also save the neck of the sphere much strain. The alterations should be made to the cross tube. The screw adjustment should be cancelled, the bronzesetblocks should be fitted with a set-up limiting spring at each end, the limiting screw can be adjusted to render the wheels parallel. With this, as far as I can see, these are subject to two stresses, front road shocks that are due to the weight of the car and inertia in a vertical direction and that in the front of the wheels due to running over a deep road gutter (caniveau). I understand that we have already increased the strength at the points which have failed and I think that it is of the utmost importance that we should also leave a round corner where the failure has commenced. The materials of this piece are at present, I understand, of about 3% nickel steel, I think that the materials might be improved by the addition of either chrome or vanadium, I believe that vanadium steel would be more suitable for drop forging. The stub axle itself should be bored out rather more to save weight and be finished so as to leave a more uniform thickness of metal and although it is very fair it would in my opinion be improved, moreover part of the steering levers can, as I pointed out before, be considerably lightened without any loss of strength. I should be glad if Messrs. Wormald and Spinney and Mr. Nadin would give this matter their immediate attention because I think that it is of the utmost importance. I do not think that a spring in the cr{Mr Cra???ster / Mr Chichester} [Handwritten notes in right margin:] X 72/2 168 [crossed out] X207 | ||