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).
Test report on a Tangye double lift screw jack, detailing dimensions, weight, and test results.
| Identifier | ExFiles\Box 52\4\ Scan042 | |
| Date | 4th March 1931 | |
| To By. {R.W. Bailey - Chief Engineer} From Hs {Lord Ernest Hives - Chair} /Lid. {A. J. Lidsey} c. to Roy. {Sir Henry Royce} x4491. Hs {Lord Ernest Hives - Chair} /Lid. {A. J. Lidsey} 8/KT.4.3.31. TANGYE JACKS. We have now completed tests on the two Tangye Jacks submitted to us under cover of ROY {Sir Henry Royce} 5/MG9.2.31, and BY3/N12.2.31, and are returning them to you for examination. Double Lift Screw Jack. This has the following dimensions etc. and is in this respect suitable for either of our chassis. Minimum height 6.187" Initial hand adjustment 4.063" Mechanical Lift 7.500" Total extended height 17.750" Weight. Jack 9 lbs 6 ozs. Handle 2 lbs 12 ozs. Total 12 lbs 2 ozs. This jack has been submitted to the test of raising and lowering on side of the front of a P.II car 50 times. It has never worked really nicely and freely, being harsh and uneven ( as regards the effort required to turn it) both with no load and with the weight of the car on it. After approximately 40 lifts the operation became distinctly harder and stiffer and the jack grunted badly. Upon dismantling the jack the following was found. Pinion and bearing. The ball bearing was not working freely, apparently due to the presence of some foreign matter, O.K. after washing. The outer race had been revolving in the aluminium housing and the inner race on the pinion shank. The housing for the outer race is not machined. The pinion teeth, rough in the first place were badly damaged. Outer sleeve. Appears to be oval, the piece which revolves inside it cannot do so easily. Small diam. screw for 2ºlift. This became very harsh and tight during use, examination shews signs of picking up on the bronze piece; appears reasonably free after washing. Possibly the metal had 'picked up' and became jambed. | ||