The RP30S Centering Arm Spring is used on Marsh R, H, Q, and S series hand-operated stencil machines. This spring applies tension to the centering arm assembly, helping the machine properly align the oilboard before each punch. If your stencil characters are drifting left or right, inconsistent, or fail to center correctly, worn or weakened centering springs are the most common cause.
This part is referenced in the OEM Front Assembly breakdown under item #6 – Spring, Centering Arm in both manuals (see Parts List, Front Assembly pages 18–19 and 35–36).
Each stencil machine uses two centering arm springs (both are shown in the OEM Front Assembly diagrams). When replacing one, it is recommended to replace both to maintain balanced tension across the centering mechanism.
The RP30S works together with several components in the centering mechanism. You may also need to inspect or replace:
If you are unsure which parts you need, call us at (770) 554-1187. We repair Marsh stencil machines in-house and can identify the correct components for your model.
