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).
Development and fitting of water excluders to address brake judder and inefficiency complaints.
| Identifier | ExFiles\Box 84\2\ scan0326 | |
| Date | 18th May 1935 | |
| +706 HE/AFM.{Anthony F. Martindale}7/KW.18.5.35. To Mr. Hives. C. to Mr. C. to Mr. To Hd.{Mr Hayward/Mr Huddy} (FOR DEPOT STREET). WATER EXCLUDERS. We have received numerous complaints from customers about low speed wet brake judders, also low speed brake inefficiency, and we have evolved a water excluder which we think will cure such complaints. During our experiments we have discovered that the jet of a hose pipe, especially a high pressure hose, is extremely penetrating, and the present excluder has been arrived at only after considerable difficulty, as practical limitations such as clearance, screening of shoes so that bedding in is impossible, production difficulties etc., have been a great handicap. We attach for your information a sketch of some of the schemes we have tried, the figures in the columns being lbs. of water that enters the brake drum in 15 mins. We have been able to produce this excluder in a suitable form for fitting to existing brake drums, thereby saving the firm the expense of fitting new drums in complaint cases. We wish to point out, however, that the sheet metal flange to be fitted to the drums is not as strong as if it were part of the casting, and if it should sustain any severe blow either in withdrawing the drum or in placing on the bench afterwards, that the clearance may be reduced to such an extent as to cause rubbing when the brakes are applied. In fitting these excluders, the first operation consists of getting the brake drums turned as per instructions. Next, all holes in the brake drum plate G.100403 must be blocked up, the outer ones with steel rivets and the inner ones that are inside the oil catcher with copper rivets. The oil catcher is to be left in position. | ||