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).
Analysis of disc and reinforcing plate specifications and an investigation into a component failure.
| Identifier | ExFiles\Box 66\4\ scan0126 | |
| Date | 31th March 1935 | |
| -2- AJS1/DB. {Donald Bastow - Suspensions} 31.3.35. of about one tenth inch, giving an overall dimension of .700, but we have found from actual trial on a car that an overall thickness of disc and plates of .850 can be accomodated. We are therefore going to try some more fabrics about .750 in thickness instead of .500 with the re-inforcing plates about .050 thick, which latter have been considered O.K. by the Hardy representative, who also thinks that his firm can get a stronger disc by compressing more layers into the same space, and also that with the combination of these two improvements we should have an increase in strength of about 50 to 65%. We do not think that the fabric taken from 98-MK had a maximum chance of life, as the re-inforcing plates were not radiused, and appeared to have cut into the outer layers, as the disc bunched up on its compression side, and probably weakened it. This bunching up was not evident on a disc (which appeared quite new) taken from 44-FK after 4000 miles running in this Country, therefore presume that severe bumping of the back axle causing varying angular velocity of the propeller shaft must have thrown enormous loads on the disc. The re-inforcing plates of the failed disc were not arranged so equi-distant as we should desire and this might also influence, although to a very small extent, the failure. | ||