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).
Girling rear brake failure on a Bentley due to a stripped thread on the brake rod.
| Identifier | ExFiles\Box 83\2\ scan0214 | |
| Date | 4th February 1938 | |
| To. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} CHATEAUROUX. 6.B.IV. - BENTLEY. GIRLING REAR BRAKES. I was, by good fortune alone, able to telegraph you this morning as follows :- " MARTINDALE 6B THREAD ON REAR BRAKEROD STRIPPED " ALLOWING ROD PULL OUT OF HEXAGON ADAPTOR ON " GIRLING EXPANDER LENGTH OF STRIPPED THREAD " 375 STOP MODIFICATION AND PARTS REQUIRED " IMMEDIATELY. WALLER. The failure occurred when braking for an acute corner at the end of a 90 m.p.h. straight. The car remained on the road. I am taking the damaged parts to show Rm.{William Robotham - Chief Engineer} before returning them to the Works for inspection. The threads on the rod are pulled over, not sheared. The threads in the adaptor do not appear to be damaged. Either the threads were badly made or else they are overstressed. We note that on several of the Wraith brake rods, the length of thread screwed into the yokes is only 1.1/4 times the diameter of the rod. The brake linkage design requires carefully checking over. ------- Rm{William Robotham - Chief Engineer}/IMW.{Ivan M. Waller - Head of Chateauroux} Ivon Waller. | ||