How to Open a Longines Pocket Watch

Opening a Longines pocket watch requires a delicate touch and a good understanding of its mechanisms. These timepieces are renowned for their craftsmanship, and accessing the movement inside should be done with care to avoid damage. This guide will walk you through the steps to safely open a Longines pocket watch, whether it’s for routine maintenance, repair, or simply to admire the intricate workings.

Step 1: Gather Your Tools

Before you begin, you’ll need to gather the right tools. Precision is key when working with fine watches, so having the correct tools will prevent accidental damage. You’ll need:

• A watchmaker's screwdriver set (preferably with flathead tips)
• A case opener knife or a case wrench (depending on the watch model)
• A loupe or magnifying glass
• Soft cloth or watchmaker’s mat

Step 2: Identify the Case Type

Longines pocket watches typically have one of two case types: snap-back or screw-back. Identifying which type of case you’re dealing with is crucial for opening it correctly.

• Snap-Back Case: This type has a simple press-fit case back that snaps into place. Look for a small lip or indentation around the edge where you can insert a case opener.
• Screw-Back Case: This case has a threaded back that screws onto the case body. You’ll notice small notches around the edge that fit a case wrench.

Step 3: Opening the Watch

For Snap-Back Cases:

1. Place the Watch Face Down: Position the watch on a soft cloth to protect it from scratches.
2. Locate the Indentation: Use the loupe to find the small lip or indentation along the edge of the case back.
3. Insert the Case Opener Knife: Gently insert the case opener knife into the lip and apply light pressure. Wiggle the knife slightly to pry the back open. Be careful not to use excessive force to avoid scratching or bending the case.
4. Lift Off the Back: Once the back is loose, gently lift it off with your fingers.

For Screw-Back Cases:

1. Secure the Watch: Place the watch face down on a non-slip surface.
2. Fit the Case Wrench: Select the correct size tips on your case wrench and align them with the notches on the back of the case.
3. Turn Counterclockwise: Gently apply pressure and turn the wrench counterclockwise to unscrew the back. Take your time to avoid slipping, which could damage the case or the watch movement.
4. Remove the Back: Once loosened, lift off the back with your fingers.

Step 4: Inspecting the Movement

With the case back removed, you now have access to the watch movement. Use your loupe to examine the intricate gears, balance wheel, and other components. Handle the movement carefully and avoid touching any parts with your fingers, as oils from your skin can affect the performance.

Step 5: Replacing the Back

After inspecting or servicing the movement, it’s time to close the watch.

For Snap-Back Cases:

1. Align the Case Back: Position the case back over the watch, making sure it’s aligned properly.
2. Press Down Gently: Apply even pressure around the edges until the back snaps into place. You may use a watch press if available, to ensure a tight fit.

For Screw-Back Cases:

1. Align the Threads: Place the back onto the case and start turning it clockwise by hand.
2. Use the Case Wrench: Once the back is hand-tight, use the wrench to fully secure it. Be careful not to overtighten, as this could strip the threads or damage the case.

Tips for Care and Maintenance

• Regular Servicing: Longines pocket watches, like all mechanical timepieces, require regular servicing by a professional watchmaker to keep them in optimal condition. This typically involves cleaning, oiling, and adjusting the movement.
• Proper Storage: When not in use, store your pocket watch in a protective case or pouch to prevent dust and scratches.
• Avoid Moisture: Keep your pocket watch away from water or moisture, as this can damage the movement and lead to rust.

Conclusion

Opening a Longines pocket watch is a task that requires patience and precision. By following the steps outlined in this guide, you can safely access the movement inside your watch for inspection or maintenance. Remember, if you’re unsure or uncomfortable performing these steps yourself, it’s always best to consult with a professional watchmaker who has the expertise and tools necessary to handle your timepiece with the care it deserves.