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).
The serious issue of faulty tappets being manufactured with faces that are out of square.
| Identifier | ExFiles\Box 35\3\ scan 023 | |
| Date | 1st January 1922 | |
| By.{R.W. Bailey - Chief Engineer} c. to Sft.{Mr Swift} c. to Ea. c. to HNV (c. HPC) EP{G. Eric Platford - Chief Quality Engineer}10/F1.1.21. X 2464 AT A.T. X 2464 RE. FAULTY TAPPETS. I must again bring forward the seriousness of the condition of the present tappets, from which we cannot obtain satisfaction as regards adjustment owing to the faces being too much out of square. As previously pointed out on various occasions, it is essential that the two end faces of the complete tappet, i.e. the face which bears on the tappet lever and the face which bears on the end of the valve stem, must be square in all possible positions of the tappet to within .002". We are not by any means obtaining this even though instructions were given some time ago for these to be manufactured quite differently, also for them to be inspected and not passed unless this condition was obtained. We are returning the sample to you, also one to Sft.{Mr Swift}, taken off the latest engine on test. These are not by any means isolated instances, and are a sample of the condition generally. They are as much as .010" to .015" out of square. As it is, considerable time has to be spent in the Test Dept. in correcting these to obtain satisfactory running engines, but even then we do not feel that they will remain satisfactory. EP.{G. Eric Platford - Chief Quality Engineer} 1922 | ||