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).
Intensive work on Bentley brakes, focusing on reducing high-speed jaggers and comparing 12' and 14' drum designs.
| Identifier | ExFiles\Box 84\2\ scan0292 | |
| Date | 5th February 1935 | |
| To E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} c. to By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} 2206 Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}24/KW.5.2.35. Bentley Brakes. In the somewhat intensive work which we have recently been carrying out on Bentley brakes we have discovered that the increased arc of contact which the Bentley brakes have appears to aggravate the high speed jaggers. We have definitely reduced high speed jaggers 80% on two cars by cutting down the arc of embrace. We feel convinced that we do not require 14" brake drums from the point of view of fading, but we now believe that they would be useful in order to enable us to get the same area of lining we have at present with reduced arc of contact. Our objection to 14" drums was of course solely on the score of weight and because of the fact that they increase the transverse moment of inertia of the front axle, which affects the steering adversely and increases the tendency to tramp. For this reason we have concentrated on trying to find out how to design a drum which should be as light as the present 12" drum, have the same stiffness, and the same cooling capacity. The attached report indicates our conclusions up to date. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||