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).
Bump test report for Woodhead 12 1/2% type front springs.
| Identifier | WestWitteringFiles\M\2October1924-December1924\ Scan40 | |
| Date | 9th October 1924 | |
| BUMP TEST. Re: 40/50 FRONT SPRINGS TEST OF LATEST PATTERN WOODHEAD 12 1/2 % TYPE SPRINGS (FT1740/1). CONDITIONS: 2" CAMS SET AT 180°. DRUM MAKES 105 R.P.M. TYRES AT 65 LBS/SQ". LOAD ON FRONT OF CHASSIS - 1000 LBS. DETAILS OF SPRING | FRACTURE | POSITION OF LEAF | POSITION OF FRACTURE FROM CENTRE BOLT | APPROXIMATE RUNNING TIME HRS. MINS. | THICKNESS OF LEAF | BRINELL AT FRACTURE --- | --- | --- | --- | --- | --- | --- Nº 003. NEAR SIDE. FT1790. 1100 LBS. | M | BOTTOM | 2" TO FRONT | 10 - 12 | .222" | 375 FLEXION: COMPRESSION = 1.67", REBOUND = 2.57". | N | 7TH (FROM TOP) | 2.5" TO FRONT | 28 - 4 | .230" | 375 POSITION OF FRACTURES. | O | " | 4" TO REAR | 28 - 4 | .230" | 363 (Diagram of spring fractures) | P | " | 8.5" TO REAR | 28 - 4 | .230" | 388 | R | 8TH (FROM TOP) | 2" TO REAR | 29 - 34 | .226" | 415 | S | TOP | 7" TO REAR | 32 - 49 | .285" | 352 Nº 004. OFF SIDE. FT1791. 1150 LBS. | T | BOTTOM | 2" TO REAR | 17 - 56 | .230" | 375 FLEXION: COMPRESSION = 1.67", REBOUND = 2.48". | U | " | 2" TO FRONT | 23 - 2 | .230" | 375 POSITION OF FRACTURES. | V | TOP | 10" TO REAR | 23 - 2 | .285" | 331 (Diagram of spring fractures) | | | | | | BAH | ||