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).
Investigation into a complaint of Bentley brake squeaks.
| Identifier | ExFiles\Box 89\4\ scan0104 | |
| Date | 16th June 1937 | |
| To Hs.{Lord Ernest Hives - Chair} from Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} Complaint Case of Bentley Brake Squeaks. B.93.HM.{Capt. W. Hallam - Head Repairs} - Mr.J.W.Howlett. In accordance with instructions received from Hs.{Lord Ernest Hives - Chair}, the brakes of the above car were carefully checked in the as received condition to see if the tipping shoes were correctly set. It was found that the clearance under each pilot shoe tip was .010" minimum, and that the pressure required to nip a .010" feeler under the pilot shoe tip was 55 lbs. - 70 lbs. on the various shoes, which is absolutely as recommended by Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} in his last two memos on this subject. By smearing each drum with blue marking, it was ascertained that the tip of each pilot shoe did touch the drum first on gentle brake applications. These findings are not surprising as the car had been to Kingsbury with the complaint of brake squeaks very recently. We have noticed on other cars (e.g. Mr.Hawkins) that if we re-bed and re-set the tipping shoes only, we get the car back very soon with a repeat complaint of brake squeaks. As we could not send Mr.Howlett's car away in the same condition as that in which it arrived, we had it relined with a lead bonded lining. We noticed that the resin from the standard M.R.lining had so coated the drum that a squeak could be obtained by rubbing a finger on the drum surface. Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} | ||