How to Unwind a Mechanical Wristwatch Properly: A Complete Guide for Long-Term Durability

Many mechanical watch owners don’t fully understand how to unwind a mechanical wristwatch correctly, which often leads to timekeeping errors, halted movements, or broken mainsprings. In this guide by King Replica, you’ll learn the working principle of the mainspring, why unwinding is essential, how to do it safely at home, and key precautions to ensure your watch runs smoothly for years.

1. What Is a Mechanical Watch Mainspring? Common Causes of Breakage

The mainspring is a thin metal strip coiled inside the barrel that stores and transfers energy in a mechanical watch. When wound manually or automatically through wrist movement, the spring accumulates tension. This energy is gradually released to power the gears and hands.

Despite its size, the mainspring bears heavy stress and can break if mishandled. Common causes include:

• Overwinding: Excessive tension can snap the spring, especially if the stop mechanism fails.
• Low-quality material: Cheap watches or knock offs often use substandard springs prone to wear.
• Wear and tear: Friction from prolonged use can degrade the spring over time.
• Improper maintenance: Dry oils, dirt, or incorrect disassembly increase breakage risk.
• Impact: Drops or strong shocks may deform or damage the spring.
• Manufacturing defects: Inconsistent material quality or poor machining can lead to failures.

2. Why and When Should You Unwind a Mechanical Wristwatch?

The mainspring is constantly under tension to store energy. When you’re no longer wearing the watch or plan to service it, unwinding helps release this tension and brings the movement back to a safe, neutral state. Here are three common scenarios where unwinding is necessary:

• Routine servicing: Relieves pressure before cleaning, oiling, or disassembly.
• Repair work: Makes it safer to work on stuck, broken, or worn components.
• Storage: Prevents wear from prolonged tension when not in use for weeks.

3. What You Need Before Unwinding a Mechanical Watch

To unwind the watch properly and safely, prepare the following basic tools:

• Small screwdriver: Precision tool matched to watch screws.
• Tweezers: For holding or adjusting small parts without slipping.
• Head loupe or magnifying glasses: For detailed view of internal mechanisms.
• Thin gloves (latex or powder-free rubber): Prevent contamination from skin oils.
• Soft cloth or anti-static tray: Safe surface for handling parts.
• Small parts container: Holds screws and components to avoid loss.

4. Step-by-Step Guide: How to Unwind a Mechanical Wristwatch

If you’re confident in your skills, follow these steps to unwind a mechanical wristwatch:

• Step 1 – Remove the Case Back: Lay the watch gently on a soft cloth. Use the appropriate screwdriver to open the back, checking if it’s a screw-down or snap-off type. Wear gloves to keep components clean.
• Step 2 – Locate the Mainspring Wheel: Look for the mainspring barrel near the winding stem. Use a loupe to identify the gear with fine teeth.
• Step 3 – Disable the Click Spring: Use tweezers or a screwdriver to gently release the click spring holding the mainspring in place. Hold the wheel firmly to prevent a sudden unwind.
• Step 4 – Slowly Unwind the Spring: Rotate the mainspring wheel counterclockwise gently. Let it release energy gradually until the tension is gone. Never let go abruptly to avoid damaging the gear train.
• Step 5 – Verify Completion: Wind the crown lightly. If it turns freely with no resistance, the mainspring is fully unwound.

5. How to Unwind a Mechanical Watch Without Opening the Case

If you’re not comfortable with disassembly, here are two safe methods you can try at home:

• Let it run out naturally: Leave the watch untouched in a stable, dry place. After 24–48 hours, the spring will fully unwind.
• Unwind via crown: Pull the crown to time-setting position, then rotate it clockwise 20–30 turns. Stop once the winding resistance disappears.

You can safely unwind your watch using only the crown adjustment.

6. Important Tips for Safely Unwinding Your Watch

To apply this technique correctly and preserve your mechanical watch, keep in mind:

• Always unwind right after removing the case back: Do it before touching any movement parts to minimize spring tension.
• Avoid force or abrupt movements: Mishandling may deform the spring or scratch delicate gears.
• Wear safety glasses when working up close: Parts like springs may snap unexpectedly.
• Clean hands and tools beforehand: Oils or dirt can harm internal components.

Proper unwinding is essential when servicing or storing your mechanical watch. Knowing how to unwind a mechanical wristwatch not only extends its lifespan but also prevents costly damage. For customers using best replica watches from King Replica, our technicians offer free unwinding services for periodic maintenance or storage.