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).
Heat damage to H.T. wiring tubes from the exhaust pipe and considering bakelite or shielded alternatives.
| Identifier | ExFiles\Box 52\1\ Scan104 | |
| Date | 5th June 1929 | |
| X4473 By. {R.W. Bailey - Chief Engineer} from EFC. {E. Fowler Clarke - Electrical Engineer} c. By {R.W. Bailey - Chief Engineer} /CS. EFC {E. Fowler Clarke - Electrical Engineer} 1/AD5.6.29. X.4473. SS. {S. Smith} H.T. WIRING TUBES AND WIRING. On the S.S. chassis we still have Vulcanite covered metal tubes for both battery and magneto ignition. Apparently we have experienced, on prolonged test of the S.S. chassis, very little effect of the radiant heat of the exhaust pipes on the magneto wiring tubes. We have however, experienced bad effects of this radiant heat on the short portions of H.T. wire emerging from the tubes to reach the sparking plugs, and we are of the opinion that means should be taken to avoid this. Returning again to the tubes, may we refer you to our report EPC2/T24.10.28, Mr. Royce's reply R4/M26.10.28, and my note EFC {E. Fowler Clarke - Electrical Engineer} 1/T1.11.28 addressed to you to which I attached a copy of Mr. Royce's report. Should we not at this point re-consider the production of bakelite tubes, both of bakelite and covered (bakelite) metal, for this purpose. In any case, it appears that we ought to consider some form of shielding for the H.T. wire to the sparking plugs from the radiant heat of the exhaust pipe. Amongst other observations, it was observed on the 10,000 miles test of chassis 22-EX, that at a mileage of 3760, the H.T. wires were badly perished and cracked due to this cause. EFC. {E. Fowler Clarke - Electrical Engineer} | ||