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).
Letter to a Mr. Chichester regarding sample clips, discussing their construction, usage, strength, and locking features.
| Identifier | ExFiles\Box 77\2\ scan0145 | |
| Date | 13th May 1920 | |
| R.R. 225A (100 T) (S.H. 159, 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2800 [handwritten] X4322 COBHAM. May, 13th 1920. SURREY. Dear Mr. Chichester. I have to thank you for your letter. As requested, I now forward Five sample Clips to fit 1-7/8, these being of slightly heavier type than previous samples. This to show that the construction & strength can be varied. May I suggest that you fit and test both these and the clips first submitted, but the lighter clip is sufficiently strong, for it should be be remembered that the device is highly efficient mechanically and certainly should not be screwed up to the limit. It is quite unnecessary. To deal with the specific points which you raise :- (a) As to the use the clips have had : Not very many have been used. About 3000 in all are in use by the Trade, [text struck through] but it is not so much the use which they have been put. [/text struck through] [handwritten above strikethrough] had to be very selective as to which they [/handwritten] Your query is largely answered by enclosed pamphlets, but further the clip has been adopted for the Dragon-fly Engine (Induction piping) and they have about 300 in use, after passing A.I.D. of course. Then, The Associated Equipment Co. use the clips. Recently they had 500 off their Order for 1000, and their further enquiry for another 2000 I had to pass as I had run out of material. The Retail Trade has had about 1500. (1) Strength &c. There is no aluminium employed. The parts may be either steel stampings or very special castings. Present clips are Mall castings treated by a special hardening process. The white appearance is caused by the Rust-proofing, which again is quite a special process. The parts are immensely strong and will not break. (2) Locking &C. The screw is B.A. which is a "slow" thread unlikely to unscrew. Further there is the friction of the point of the Bridge. Official and other tests have dealt with this. For aircraft they required a hole through the screw-head, for locking with a wire, and it is found that such wiring is unnecessary Contd. | ||