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).
Experiment with a contact breaker arm fitted with a fibre bush and fibre rollers.
| Identifier | ExFiles\Box 4\5\ 05-page047 | |
| Date | 15th August 1914 | |
| Wor{Arthur Wormald - General Works Manager}/Sill/115814. August 15th.1914. J.{Mr Johnson W.M.} H.{Arthur M. Hanbury - Head Complaints} M.{Mr Moon / Mr Moore} TUG. X 430 Report on Contact Breaker Arm fitted with fibre bush & fibre rollers. This experiment was put through because of complaints that this part seldom gets oiled, we use now hardened steel rollers and bush which sometimes squeak. One contact breaker arm made in this way ran 10,500 miles, another one has run 5,500 miles on #300. Examination shows that on both of these arms the fibre bush has tightened on the pivot pin and this has caused the steel bush to work in the arm. The fibre rollers have worked quite freely and there is practically no wear on them. The arrangement as a whole is not an improvement over what we are using, the contact breaker which ran on the 10,000 miles bench test was a standard one, it was in perfect condition at the finish, it was not oiled at all. Fibre we know from past experience is not very reliable and if we can possibly do without it I think we should do. I think we might try a bronze bush for the pivot pin bearing, we very rarely get any trouble with the steel rollers, I should suggest leaving them as they are. | ||