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).
Blueprint with cross-sections and handwritten notes for a modified damper piston.
| Identifier | ExFiles\Box 56\1\ Scan110 | |
| Date | 19th March 1931 | |
| NSM 3266 MAKE DRAW THE MINIMUM THAT CAN BE USED FOR MACHINE MOULDING. WE SHOW 1° THE FLAT FACE HAS TO BE PROVIDED IN ADDITION TO THE THREE BOSSES TO PREVENT ROTATION OF PISTON THE THREE HOLES ARE THE SAME DIA .187 FOR ECONOMY IN DRILLING BORE IS .375 TAPPING = .325 BALL .300 DIA STEM .312 DIA ADJUSTMENT WASHER IS LESS IN DIA THAN FLATS OF HEXAGON TO AVOID DAMAGE TO JOINT FACE. WORKS HAVE ASKED FOR PLUGS MADE FROM HEXAGON BAR WHEREVER POSSIBLE PISTON OF C/I DAMPER PISTON MODIFIED TO RZ/M3-4-31 11/3/31 EXISTING DAMPERS OF PHAN. TYPE 19/3/31 NSM 3266 ALTERNATIVE VALVE CARRIED IN PLUG NON-INTERCHANGEABILITY OF VALVES WITH .025" CLEARANCE BETWEEN VALVE AND STOP (SUGGESTED IN R {Sir Henry Royce} /M20-2-31) THE VALVE PARTS CANNOT BE INTERCHANGEABLE WE DO NOT SEE HOW TO RENDER THEM NON-INTERCHANGEABLE WITHOUT EXTRA EXPENSE. WE SUGGEST THAT WITH SPRINGS ON THE VALVES THEY ARE LESS IN NEED OF STOPS THAN THEY ARE ON OUR PRESENT DAMPERS. IF IT IS THOUGHT THAT A STOP WITH CLEARANCE BETWEEN .025 AND .050 IS BETTER THAN NO STOP WE COULD PERHAPS PROVIDE THIS WITH INTERCHANGEABLE PARTS. NO WASHER WOULD BE USED IN THIS CASE OF COURSE WHEN CONSIDERING THE MOULDING OF THE PISTON ON PREVIOUS OCCASIONS, IT. HAS APPEARED TO US THAT THE INCREASED WEIGHT WITH VERTICAL MOULDING AS SHOWN HERE WOULD NOT BE ACCEPTABLE | ||