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).
Instruction sheet and report on testing magneto and battery ignition spark gaps.
| Identifier | ExFiles\Box 52\1\ Scan043 | |
| Date | 29th June 1920 | |
| RR 330 (100 BKS) (SH57. 29-6-20.) MP 224359 ROLLS-ROYCE LTD. INSTRUCTIONS. To ______________ Order No. 3. Customer's No. ______________ | SPARK GAP NO. | MAXIMUM GAP ALLOWING REGULAR INDUCED SPARKS TO JUMP | |---|---| | 6. | .025" | | 5. | .020" | | 4. | .020" | | 3. | .016" | | 2. | .012" | | 1. | .008" | Gap NOS correspond to Cylinder NOS on Engine Upon earthing the battery ignition wires there was no appreciable difference in the intensity and regularity of the magneto sparks on 5.5 m.m gaps in air. With the magneto disconnected and the battery ignition wires sparking, small induced sparks could also be obtained from the magneto wires at the respective spark gaps but of a much smaller magnitude as shown in the following table :- Signed contd This Sheet must be filed on completion of the work. | ||