Purpose of the Arrow-Marked Screw on the Barrel Bridge

Your South Bend 16-size Model 2 (Grade 209) has a unique arrow-marked screw on the mainspring/barrel bridge. This isn’t just a regular screw – it’s a winding/setting lockout mechanism present on all South Bend 16-size pendant-set movements. Turning this screw as indicated by the engraved arrow locks out the setting mechanism, effectively keeping the watch in winding mode regardless of the stem position. South Bend added this feature to make servicing easier – for example, it allows the watch to be wound or the mainspring to be let down even when the movement is out of its case (when normally a pendant-set movement would slip into “setting” mode outside the case). In short, turning the screw counter-clockwise (as the arrow shows) locks the watch in wind mode, while turning it clockwise (against the arrow) restores normal pendant-set function.

Before Removing the Barrel Bridge (Disassembly)

When preparing to disassemble the watch (specifically before removing the mainspring/ratchet wheel bridge), you should use the arrow screw to safely disengage the setting function and deal with the mainspring power:

• Lock the Winding Mode: Turn the arrowed screw in the direction of the arrow (anti-clockwise) until it stops. This will lock out the setting mechanism, keeping the clutch engaged in winding position at all times. With the pendant-set mechanism locked, the crown (or a bench key) will only wind the mainspring, regardless of stem position.
• Let Down the Mainspring: With the movement now locked in wind mode, carefully let down the mainspring before removing the bridge. Hold the crown (or bench key) firmly, release the click, and allow the mainspring to unwind slowly under control. The lock screw prevents the keyless works from slipping into “set” position during this process, so you won’t get that sudden release of an uncontrolled unwind. In other words, the arrow screw locks the crown wheel to the mainspring, letting you safely release mainspring tension without the mechanism jumping into hand-setting mode.
• Remove the Bridge: Once the mainspring is fully let down and there’s no power, you can proceed to remove the barrel bridge. The setting components (yoke, sliding clutch, and the round spring that pushes on the setting lever/yoke) will be held in the winding position by the cam on that arrow screw. This helps prevent parts from flying out or shifting under spring tension when you lift the bridge. Nonetheless, take care during disassembly to note how that round yoke spring sits against the cam – it will need to go back the same way during reassembly.

After Reassembly (Restoring Normal Operation)

After cleaning/repair and reassembling the movement (with the barrel bridge and keyless works back in place), you’ll need to re-enable the normal winding/setting function:

• Unlock the Setting Mechanism: Turn the arrowed screw clockwise (opposite the arrow) until it returns to its normal position. This rotation of the cam removes the lockout, allowing the yoke and sliding clutch to move freely when you pull the stem in and out. In essence, you are switching the watch back to regular pendant-set mode.
• Function Test & Stem/Sleeve Adjustment: With the lock screw back in the normal position, test the crown in both positions. When the crown is pushed in, it should now engage the winding gears and wind the watch; when the crown is pulled out, it should shift the clutch to engage the setting gears and move the hands. If the watch winds in one position but won’t set (or vice-versa), double-check that you’ve fully returned the arrow screw to the proper position (it should be turned all the way clockwise to disengage the lock). In a South Bend pendant-set design, the case sleeve and stem work together to hold the crown in the wind or set position. If everything was correct before, you typically do not need to readjust the sleeve – just ensure the stem (male piece in the case) is properly inserted into the movement and that the sleeve’s tension lets you snap the crown in and out of position with a firm click. The keyless works should now function normally, with winding in the “in” position and hand-setting in the “out” position. (If you had removed the stem or disturbed the sleeve, you may need to tweak the sleeve tightness so the crown’s detent positions feel correct, but this is the same procedure as with any pendant-set pocket watch.)

Remember, before removing the barrel bridge, turn that marked screw anti-clockwise to lock the watch in winding mode and fully let down the mainspring.

After reassembly, turn the screw back clockwise to restore normal wind/set behavior. This clever South Bend feature ensures your Grade 209 will wind or let down safely on the bench, and then go right back to operating in both winding and hand-setting modes once you’ve put it all back together. Good luck with your first South Bend – once adjusted correctly, the stem should pull in/out and function in both positions as intended!