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).
The design specifications for a jack handle, comparing various options and making a recommendation for an order.
| Identifier | ExFiles\Box 52\4\ Scan021 | |
| Date | 18th February 1929 | |
| ROY {Sir Henry Royce} /GEA12/EB18. 2. 29. - 2 - "2'-1" long, weighing 2 lb. and the Dunlop "Super D.L." "handle is 3'-5", weighing about 2 lb. 10 oz. "We note your views on the question of using a tubing "handle, but as this would be greater in section than "the solid one, and a square tube would have to be at "least 3/4" over the corners, a small reduction in weight "would be possible, but we would point out that the "square tubular telescopic handle is not adaptable to "the Brace type of handle without an increased length "when fully closed. "In our opinion, the joint we propose, as per the sample "you have seen in the case of the 2 1/2-ton Jack, is a "superior joint to that used with the sample one-ton "Jack you have already seen, and better still than the "handle of the competitors mentioned above. "The effort required to operate the Jack for greater "loads than 1/2 ton, we consider would be too great for "the Brace Handle. "In regard to the inclination angle of the Handle, to "increase this would need new patterns for gears, and "alterations to the body, and would necessitate some delay "in delivery, and as we have stated above, we do not wish "to alter this inclination if it can possibly be avoided. "We should suggest that for the 100 Jacks you now propose "to order, you take a handle exactly as the sample "suggested, and that would leave you time to develop this "question of handle to your satisfaction for future "supplies. "We hope this will be to your satisfaction, and await "your further instructions". ROY. {Sir Henry Royce} | ||