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 Houde Engineering comparing American-built and French-built Houdaille instruments.
| Identifier | ExFiles\Box 25\2\ Scan129 | |
| Date | 31th January 1927 | |
| HOUDE ENGINEERING CORPORATION Buffalo, New York January 31, 1927 Mr. Maurice Olley, Rolls-Royce of America, Inc. Springfield, Mass. Dear Sir: As per request of Mr. B. D.{John DeLooze - Company Secretary} Shultz for the comparisons showing American Built Houdaille Instruments with those of the French Built Instruments, we are submitting the following:- In the first place, our equipment is of the most up-to-date type. All grinding operations are carried on either thru cylindrical Blanchard Surface or Heald Grinders. Parts as they come from the different machines are such as to require no hand work and the accuracy is such that our small FA instrument is equal in resistance to the large type French instrument. Wing and Wingshaft forgings are of Molybdenum Steel, triple heat treat-ed{J. L. Edwards} against carbon or low nickle steel annealed. Wings and Wingshafts are precision ground on all working surfaces and no hand fitting is used in the assembly. Wingshafts and Levers are serrated against the French type which are squared and there is not a possible chance of any loosening up after assembling. American levers are 35 carbon steel, heat treated, to 35 scleroscope. Whereas the French are of low carbon steel and apparently not treated. The ball joint used in the drag link is bronze seat bearing against a hardened ball. The bronze seat is held against the ball by means of helical spring. Whereas, the French type there is steel against harden-ed{J. L. Edwards} steel ball and a flat steel washer used to take up slack. Invariably these washers bend or break almost immediately. The American construction places the wing in a vertical position. The French instrument in a horizontal position. | ||