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).
Visit to Borg & Beck Works regarding cracking issues with Phantom III clutch facings during drilling.
| Identifier | ExFiles\Box 129\1\ scan0244 | |
| Date | 17th August 1937 | |
| Sgd from Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler} c. Hs.{Lord Ernest Hives - Chair} c. Hy.{Tom Haldenby - Plant Engineer} c. RHC.{R. H. Coverley - Production Engineer} VISIT TO BORG & BECK WORKS, LEAMINGTON SPA. Re. PHANTOM III. Clutch. Visit made in response to Borg & Beck's letter of the 13th inst. Great difficulty is experienced with the Thermoid facings developing circumferential cracks from hole to hole during drilling. Borg & Beck had received 232 facings for 100 discs, but showed me 33 which had cracked or broken during drilling, most of them too badly to use, although a few may be usable. Various drills have been tried with different speeds and feeds. They are cabling the Thermoid Co. to ask if any special method of drilling is known. It was observed that there were numerous similar cracks in the facings of the six Thermoid faced discs made and assembled by the Long Co. of America. No failure of a disc showing cracks has so far been recorded, but their existence causes some anxiety. Borg & Beck are making a rig to spin the assembled plate at high speed, and a number of discs showing cracks will be tried to determine the bursting speeds, this rig will be ready in about a week, and they will advise us when it is ready. Several of the plates received by us had excessive run-out, in one case up to .050". I was told that Borg & Beck's Chief Inspector had personally passed these discs with a maximum run-out of .010 before despatch, and it is thought that the run-out may have suffered in transit or subsequent handling, and an improved method of packing is being adopted. With regard to delivery of the 100 discs now on order, 11 had been received prior to this week (these were absorbed by replacements for customer complaints as fast as they arrived.) 13 more have just been received, and 12 more are promised this week, after which there will be a hold-up continued | ||