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).
Comparison of wheel testing methods and formulae between Kelsey Hayes and Vauxhall.
| Identifier | ExFiles\Box 159\7\ scan0285 | |
| Date | 20th November 1940 | |
| Rm{William Robotham - Chief Engineer}/GB.2/ET.20.11.40 - 2 - Messrs. Inglis and Aylward agreed to put up a proposition on Aluminium alloy rims on steel centres and were to study a German patent on extruded alloy wheels. This concluded the meeting. During the drive to the station, wheel tests were discussed and Kelsey Hayes gave details of their tests. This is compared with the Vauxhall tests. The latter was based on information given by Kelsey Hayes and Opel. On both tests, the wheel is secured to a revolving face plate. A bar three feet long is fixed to the wheel centre and carries a weight at the free end. The formulae for determining the test loading are as follows:- | | Kelsey Hayes | Vauxhall | | :--- | :--- | :--- | | Load to be applied to wheel in Lb.ft. | Loaded car wt x 7/16" | Loaded car wt x 3/8" | | Number of revolutions of wheel required. | 25,000 to 30,000 | Not less than 35,000 | | Speed of rotation of wheel. | 44 r.p.m. | 30 r.p.m. | | Definition of loaded car weight. | Kerb wt. + 500 or 750 lb. according to size of car. | Kerb wt. + 700 lb. | Kelsey Hayes measure the 3 ft. from the bolting face of the wheel and Vauxhall from the centre line of the tyre. Test loads for the Myth by the two formulae would be as follows:- Kelsey Hayes (2464 + 500) x .4375 = 1298 lbs/ft. Vauxhall (2464 + 700) x .375 = 1188 lbs./ft. | ||