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).
Testing a polished worm steering system, its performance under load, and the effects of various lubricants.
| Identifier | ExFiles\Box 154\3\ scan0015 | |
| Date | 11th March 1927 | |
| Oy2-E-31127 -3- March 11, 1927. With the polished worm as described above the new steering is more readily reversible when first put on the rig, than formerly after 30 mins. cranking. The rig was next used for testing for sticking under parking conditions. The load of 440 lbs. on the pendulum lever, corresponding to 4200 lbs.ins. at the steering pivots, is equivalent we find to twisting the wheels with the car stationary, fitted with 6-3/4 ribbed tires, on a fair macadam surface. (On dry concrete this will increase to 8000 lbs.ins. for the two wheels.) With the polished worm as described above there was no sticking under 440 lbs. load at room temperature, except with "Caspar" oil (similar to Wakefield Castrol). Alemite Winter grade transmission Oil, Gredag 62, (heavy graphite lubricant), Sinclair Opaline (high-grade transmission oil), Straight Castor, all stuck badly before the temperature reached 150°F.{Mr Friese} "Iso-Vis" gear oil (Standard Oil of Indiana special "all-weather" transmission lubricant) behaved perfectly at all temperatures up to 175°F.{Mr Friese} We are therefore taking all possible steps to get this in all our steerings. We found however that on a steering without sufficient polish on the worm the change of lubricant made only slight improvement. We are therefore arranging to polish all steering worms already in chassis. We all feel that we have now got the steering into a satisfactory condition. Yours very truly, MO/E Maurice Olley | ||