Check symptoms of worn crown tubes and threads, and see when water resistance is likely at risk.
Crown tubes and threads are part of the sealing system on screw-down crowns. Wear, damage, or poor engagement can prevent a reliable seal even if the crown appears closed.
If engagement is vague, gritty, wobbly, or moisture has appeared, keep the watch dry until inspected and pressure-tested.
A watchmaker can assess tube condition, crown threads, gaskets and sealing surfaces. Worn tubes/threads may need parts replacement, not just a new gasket.
Why is my screw-down crown loose? Possible causes include worn threads, worn tube, bad gasket, or incomplete engagement.
Can a worn crown tube ruin water resistance? Yes. Tube/thread wear is a common reason screw-down systems stop sealing reliably.
What does cross-threading feel like? A catchy, off-angle resistance instead of smooth even engagement. Stop and realign rather than forcing it.
Should I swim with a vague crown seal? No. Keep the watch dry until it is inspected and tested.