Micro-examination report on a Wraith front suspension coil spring that failed a bumper test.
| Identifier | ExFiles\Box 9\5\ 05-page039 | |
| Date | 24th March 1937 | |
| Micro-Examination Report. 646 M.1276. To Rm {William Robotham - Chief Engineer} /Gry. {Shadwell Grylls} HL4/AG.24.3.37. Laboratory. Re: Wraith Front Suspension Coil Spring GW.432, Failed on Bumper Test. This is a preliminary report to confirm that we have examined the fracture in the end coil of the above spring and find that it has started from one of the marks etched on with the electric etchograph. It was arranged with Mr. Leslie that the spring should be returned to us later for a more complete examination if this is required. We have previously shown that the use of this method of marking can be dangerous (Reports M.1054 and M.1055), since the arc locally melts the surface of the steel producing fully hardened areas containing small cracks. Hl. | ||
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).