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).
Standardisation and issues found with B.II and B.III dummy shutter sets.
| Identifier | ExFiles\Box 99\4\ scan0063 | |
| Date | 4th July 1938 | |
| 440 also 240. To Ry. from Rm{William Robotham - Chief Engineer}/Std. c. RHC.{R. H. Coverley - Production Engineer} c. Roy.{Sir Henry Royce} c. Da.{Bernard Day - Chassis Design} B.II AND B.III DUMMY SHUTTER SETS. When the B.II dummy shutter set was standardised for 'M' series production, an arrangement drawing (IB.3416) was made from the sample set of shutters approved (for appearance) by Sales, giving important external dimensions, limits etc., and the gap between the centre shutters was specified as .500, as per sample set. Further, when the first B.III radiator was being detailed with dummy shutters, it was decided to make the centre stiffener common to B.II and B.III radiators, since this piece represented about £70 tool cost. Accordingly a detail drawing of this centre stiffener was made and forwarded to Messrs. Marstons in order to ensure that the piece they made for B.II shutter sets would be usable for B.III. However, although the scheme for B.III called for .4375 centre shutter gap and therefore the centre stiffener was detailed for same, this fact was overlooked when the same stiffener was adopted for B.II, and has only now been realised. The result is that when assembled, there is a gap between the stiffener tabs and the vanes of approx. .030", which is filled by solder on the shutter sets so far supplied. Since a production set of shutters has been available for inspection we have been of the opinion that the centre gap could with advantage be reduced slightly from an appearance standpoint, since it appears greater than the individual shutter gaps - the contour of the centre shutters has already been altered in order to endeavour to give some improvement in this direction. We have, however, not suggested modification of the shutter spacing to alter the gap since we were under the impression that this meant new tools for the centre stiffener. | ||