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 from a supplier discussing bellows specifications, tolerances, and production inquiries.
| Identifier | ExFiles\Box 151\2\ scan0152 | |
| Date | 20th January 1934 guessed | |
| - 2 - Messrs. Rolls-Royce Ltd. our files the following drawings:- Termopans F. {Mr Friese} 85875. HS. {Lord Ernest Hives - Chair} 1242. F. {Mr Friese} 100692. Ex.10836. Ex.10112. Inner G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 80998. F. {Mr Friese} 100773. Indepr G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 80609. Would you be good enough to let us know which, if any, of these parts are in production? The sizes of bellows called for are No.4 No.6 and No.8, having nominal outside and inside diameters respectively of 1.1/8" x 3/4", 1 1/4" x 15/16", and 1 1/2" x 1". In order to put the matter right once and for all, we would suggest supplying No.4 and No.8 to the following limits:- No.4. o {Mr Oldham} /d. 1.125" - .050". i/d 25/32" ± 1/32" No.8. o {Mr Oldham} /d 1.500" - .050". i/d.1.1/32" ± 1/32". With regard to No.6, we are making a slight modification to the tools and should like to leave the statement of the definite size until this modification is completed. It occurs to us that this may not be a size which it is your intention to use. While we admit that these tolerances may appear to be on the large side, if the method of manufacture of the bellows is considered they are not by any means excessive and come well within the limits generally specified by manufacturers of bellows in the United States and in Germany who normally are unwilling to guarantee their diameters closer than ± 1/32". If in future you could give us an indication when a part is likely to be put into production we will make any comments which may seem desirable as a result of our experience in building up the small quantities which we believe usually precede production orders. Yours truly, THE PACKLESS GLAND CO. LTD. W.Martin-Hurst. | ||