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 the new Dunlop Super Double Lift Jack.
| Identifier | ExFiles\Box 48\1\ Scan049 | |
| Date | 14th May 1930 | |
| BY. {R.W. Bailey - Chief Engineer} From HS {Lord Ernest Hives - Chair} /AJL. X4124. Hs {Lord Ernest Hives - Chair} /AJL.2/MJ.14.5.30. DUNLOP SUPER DOUBLE LIFT JACKS. We have tested the new type Dunlop Super Double Lift Jack submitted for our criticism and described in a letter from Dunlops (FRC.EW-21 of May 9th.1930). The jack has successfully passed the test we put it through viz:lifting the whole of the front of a large 40/50 car twenty-five times through its maximum range of movement. Upon examination of the jack after the tests it was found that the screws and their nuts were in better condition than any we have previously tested. The bevel wheel and pinion were also in very good condition. The jack appears to require less effort to operate it than the average standard type Double Lift Jack, although the effort required when lifting on the large thread (four threads per inch) is noticeably greater than the effort required when lifting on the small thread (five threads per inch); this however, is never really excessive, certainly no more than the average standard jack. The shape of the jack is certainly better and less cumbersome than the standard. The universal attachment for the handle is good, but we think could be improved. As you will see from the jack, the case has been damaged by the boss on the handle rubbing | ||