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).
Test report on different plate designs, comparing vulcanised facings, riveting methods, and materials, with references to Ferodo and Borg & Beck.
| Identifier | ExFiles\Box 129\3\ scan0310 | |
| Date | 22th June 1936 | |
| -2- Hs{Lord Ernest Hives - Chair}/Smth.6/KW.22.6.36. (4) Special plate of which the facings were vulcanised on to thin steel backing plates. Facings flew off backing plates at 4800 r.p.m. hot, due to poor adhesion. (5) Original R.B. type plate with staggered segments lined with 'No.6'. Only very slight movement of one of the segments from the inner rivets at 4800 r.p.m. hot. These rivets were too deeply countersunk. The conclusion from these tests is that the new disc with thicker facings is considerably stronger than the old type, but that we cannot yet say that we shall be entirely immune from trouble. We are continuing tests with modified plates using different systems of rivetting. Regarding E's suggestion that the manufacture of the facings should be altered in such a manner as to give a purely circumferential weave, we took this point up with Ferodo some time ago. They said that it was impossible to impregnate a fabric of this structure with rubber satisfactorily. At the moment we regard the R.B. plate lined with "No.6" as the most promising development. This plate allows the use of a great number of fixing rivets. We have one now running in JJ-EX and it gives a very smooth take up so far. We have found a staggering of 'O,O"' to be better than .015". We are pressing forward with this line of development. As another experiment we are making at Derby a centre plate similar to the Long plate which has now satisfactorily completed about 20,000 miles in JJ-EX. The facings of this plate are more securely rivetted than in the Borg & Beck type. Borg & Beck made us a copy of the Long plate a short time ago, but it jaggered in a car. We think, however, that this can be accounted for by the irregularity with which the cushioning springs were fitted. Hs{Lord Ernest Hives - Chair}/Smth. | ||