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).
'loft layout' drawing principle and Cadillac's use of large monster drawing boards.
| Identifier | ExFiles\Box 178\2\ img037 | |
| Date | 7th March 1940 | |
| Serial No. 7 Rn.{Mr Robinson} page 4 OY 7/D/Mar.7.40 V.M. Ltd. have a lot of notes and experience on this, and I think should figure with Manning in any drive you have in mind to improve coachwork. 7) Am going to irritate you further on the "loft layout" principle by sending you details of the Cadillac monster drawing boards. Cadillac were pioneers of this system, which was introduced in chassis work about 1935, and is now used by everyone here. This is not the super high-priestly method of drawing on enamelled aluminum sheet, used in coachwork, which found an unfortunate entrance into engine and chassis work about 1930. The aluminum sheet method was almost worse than the earlier methods of self-hypnotism practised by all draftsmen. The Cadillac system uses shrinkproof tracing paper(synthetic wax base) and a black pencil with a round point, or a fat blue pencil. A complete new model chassis is laid out full scale in three views with straight line and free-hand sketching methods, and has in this form all the accuracy which is going to be obtained in the finished car. Prints can be taken off at this stage and the experimental shop works to them with a few leading dimensions. After the car has proved itself out, better details are made and from these a more careful final layout is made on the big board and kept as a permanent record. The draftsmen who work on the big board get plenty of exercise and don't get constipated. R.R. may do this already. I don't know, but am taking a chance Seaholm says all their original work has been done on the big board for years, and that it is the best thing they ever did. OY | ||