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 a complete clutch removed from a customer's car, noting excessive heat, slipping, and the condition of the Thermoid facing.
| Identifier | ExFiles\Box 107\3\ scan0159 | |
| Date | 20th February 1939 | |
| 561 W/N. c. to Hd.{Mr Hayward/Mr Huddy} c. to By/TB. Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler}9/JH.20.2.39. GMC.11. C.J.U. Palmour Esq. We have just examined a complete clutch removed from above car, and understand that the mileage is about 10,000 since the Thermoid was fitted. The appearance of the pressure plate suggests that the driven is a confirmed clutch-slipper it is badly discoloured by heat, more so in fact than many experimental clutches which we have most deliberately subjected to brutal driving methods, also the springs are some 10% down, which again suggests excessive heat. The appearance of the Thermoid confirms the idea of vicious slipping, and there is some indication (but not clearly defined) that it may have been oily at some time. We would be interested to have any information you may be able to give us as to the driving of this owner (or driver?), also the mileage of the facings prior to Thermoid and whether replaced on account of wear or judder. We note that the Thermoid, even in this case, shows no appreciable wear, and we cannot recall having seen Thermoid fairly worn, i.e. when not destroyed by tearing or by oil. You will appreciate that we are always anxious to add to our experience by reports on cars in customers hands. Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler} | ||