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).
Specification and comparison sheet for the front springs of American Chassis S-107-MK.
| Identifier | ExFiles\Box 43\2\ Scan062 | |
| Date | 17th July 1920 | |
| W.12.S.17 FRONT SPRINGS OF AMERICAN CHASSIS No S-107-MK S OF RIGHT HAND SIDE FRONT SPRING. REFER TO SIMILAR SPRINGS MANUFACTURED BY FLETCHER-LADBROKE WASBRO'. First Table: | | AMERICAN. | FLETCHER-LAD | |---|---|---| | NO OF PLATES | 14 | 14 | | LOAD AT CAMBER ON SPRING) | 1055 LBS. | 1050 LBS | | " " " AS TESTED) | 1028 " " | 1032 " " | | INITIAL CAMBER (HT'S TEST) | 3.312" | 3.375" | | WEIGHT OF COMPLETE SPRING | 42 LBS. | 39 3/12 LBS. | Second Table: POSITION ASSUMED BY PLATES WHEN UNDER H/F LOAD AND WITH CENTRE BOLT REMOVED. | PLATE No | THICKNESS OF PLATE AT CENTRE | GAP BETWEEN ADJACENT FACES OF EACH PAIR OF PLATES | DISTANCE FROM CENTRE TO CENTRE OF EACH PAIR | |---|--- |--- |--- | | | AMERICAN | WOODHEAD | AMERICAN | WOODHEAD | AMERICAN | WOODHEAD | | 1ST | .272" | .29" | .550" | .550" | .812" | .812" | | 2ND | .258" | .234" | .550" | .550" | .793" | .717" | | 3RD | .229" | .221" | .475" | .475" | .698" | .691" | | 4TH | .218" | .211" | .300" | .325" | .508" | .538" | | 5TH | .199" | .216" | .425" | .250" | .614" | .463" | | 6TH | .180" | .211" | .050" | .175" | .228" | .303" | | 7TH | .177" | .225" | .150" | .250" | .330" | .450" | | 8TH | .184" | .175" | .175" | .275" | .356" | .462" | | 9TH | .179" | .170" | .100" | .175" | .279" | .382" | | 10TH | .179" | .178" | .075" | .250" | .251" | .424" | | 11TH | .174" | .172" | .100" | .275" | .276" | .480" | | 12TH | .178" | .183" | 0 | .100" | .181" | .280" | | 13TH | .184" | .177" | 0 | 0 | .179" | .168" | | BOTTOM | .175" | .167" | | | | | | ||