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 outlining the rationale for continuing in-house production of crane motors, with several design and manufacturing suggestions.
| Identifier | ExFiles\Box 180\M6\ img030 | |
| Date | 28th August 1928 | |
| "ELMSTEADHenry Royce's home in West Wittering" WEST WITTERINGHenry Royce's home town. CHICHESTER. 28th. August 1928. To The Directors of ROYCE LTD. Copy to Mr. Bentley. ✓ " " Coley. My dear Mr. Claremont, Mr. Allcock, Mr. Hulley. CRANE MOTORS. The reason why we should continue to make our own motors is as follows:- In addition to their contribution to the charges we find that the only ones we can buy at a profit over our own costs with the charges that are usually allotted are the very lowest priced ones made by firms with little reputation, working in a small way. The result has been that buyers have specified some make like B.T.H., Westinghouse, etc, and this has caused us great cost and expense in adapting our designs to a variety of makes and sizes. [handwritten: casings] Now in constructing our own you will see that we can adapt the machine specially for crane work, which means that the shaft and bearing are made suitable for carrying the brake drum and pinion, without the trouble of fitting coupling outboard bearings, and the difficulty of 3 bearings in line. Also I have hope that we can scheme a smaller higher speed machine with features to reduce the wiring and collector gear. The following are a few suggestions:- (1) Let us limit ourselves to a few sizes, say 6., suitable for the crane trade - i.e. 2-3., 5-7½., 10-15., two lengths of each stamping, say 3 stampings. [handwritten: (pairs)] (2) Make the main bearing and shaft long enough for either fan or brake pulley and pinion. (3) Use roller bearing at main end, ball at minor end, because rollers carry real load better than balls - i.e. of brake and pinion. (4) Get to know if possible where B.T.H. or some standard maker get their stampings, and buy exactly the same. [handwritten: if suitable] (5) Adopt 6 pole winding for the larger sizes - 1000 revs., and 4 pole winding and 1500 revs. for smaller sizes. Stick to standards even if you give something away. (1) | ||