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).
Letter from The Herbert Frood Company regarding the performance and testing of new non-wire asbestos brake linings.
| Identifier | ExFiles\Box 26\4\ Scan078 | |
| Date | 8th January 1920 | |
| C O P Y The Herbert Frood Company Ltd., Sovereign Mills, Chapel-en-le-Frith. England. 8th January, 1920. Thursday. Reference HF{H. W. Frost - Coachwork Inspector}/MP. Order C.J.894. Messrs Rolls, Royce Ltd. Nightingale Road, D E R B Y. Dear Sirs, re No.9.NON WIRE NEW DEPARTURE BRAKE LINING. On March 31st last we had pleasure in sending 72 segments to your plan C.4574 as a test, and we shall be glad to know the fate of these segments. To freshen your mind on the subject, this is a brake lining which we can make of woven or unwoven asbestos the latter we are merely waiting for machinery to produce, which will stand very high pressures, easily 5 tons per square inch without detriment. It is impervious and insoluble. We are now able to say that very careful tests have been made by the London General Omnibus Co. and they have, for the first time, been able to report that our brake linings No.9. on their country buses have not required renewal during the period of 12 months, and they have tested the No.9. throughout their services. The writer has been trying it on one of your cars, in his personal use, and he is not quite satisfied with it on the footbrake, but as the segments had been previously distorted, he wonders whether that may have any effect, the braking was not quite so keen as with our ordinary die-pressed fabric on the footbrake, but on the hand brake, strange to say, the effect is keener than with our ordinary standard die-pressed fabric. We are ordering up some further steel foundations to make further tests, but in both cases, although we have attained about 4000 miles during the tests, and these have been very severe at times, as for instance, putting the throttle full open, and the brakes hard on down a steep hill, we have been pleased and surprised to note that there is no appreciable wear of the linings, and the drums are in their original condition. | ||