How Do You Set the Moon Dial on the Westminster Grandmother Clock Kit?

Westminster Chime Grandmother Clock Kit GMKIT2

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Westminster Clock Moon Dial

If you recently purchased the Westminster Grandmother Clock Kit GMKIT2, congratulations—you now own one of the most classic, elegant, and complete mechanical clock kits available today. This clock kit includes a beautiful moon phase dial that tracks the lunar cycle, adding a charming celestial element to your timepiece. But to fully enjoy the moon dial, you’ll need to set it up correctly—so the sun shows during the day and the moon at night.

Let’s walk through how to do that the right way, step by step, using only the components included in the GMKIT2.

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What Is the Moon Dial on the GMKIT2 and What Does It Do?

The moon dial is the rotating disc at the top of your clock’s face, decorated with images of the moon and stars on one side and the sun and sky on the other. It’s not just decorative—it actually tracks the 29.5-day lunar cycle, helping you keep time the way clockmakers did centuries ago.

In the Westminster Grandmother Clock Kit GMKIT2, the moon dial syncs with the gear train inside the German-made mechanical movement. When correctly set, it rotates once every 29.5 days, showing you the current phase of the moon as it would appear in the sky.

Why Should the Sun Show During the Day and the Moon at Night?

Setting the moon dial properly enhances the visual harmony of your clock. When the sun is centered at high noon, the dial looks natural and tells a story: it’s day. When the moon comes around to the top at midnight, your clock reflects the night sky. This alignment isn’t just visually satisfying—it’s the way traditional moon dials were always meant to be used.

How Do I Set the Moon Dial on the GMKIT2?

Follow these steps to set the moon dial on your GMKIT2 so that it displays the sun during the day and the moon at night.

Step 1: Install the Movement and Moon Dial

Before adjusting the moon dial, make sure you’ve properly installed the movement included in your GMKIT2. This kit includes a Hermle mechanical movement, designed to drive both the hands and the moon phase dial. Follow the installation instructions that came with the kit, and secure the dial to the front of the movement with the supplied hardware.

If you’re missing the instructions, you can find full setup information and replacement parts directly on the GMKIT2 product page.

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Step 2: Advance the Time to Midnight

Use the minute hand (not the hour hand) to advance the clock until midnight. You can do this by watching the chimes—wait until the clock finishes chiming twelve times, then stop.

Midnight is when the moon should be centered at the top of the dial. This helps you synchronize the moon dial’s position with the clock’s timekeeping mechanism.

Step 3: Manually Rotate the Moon Dial

Once you’ve reached midnight, gently rotate the moon dial (by hand) until the moon image is centered at the top of the dial window. Most moon dials have a notch on the side that allows for easy manual adjustment.

Important: Never force the moon dial. If it feels stuck, double-check that the dial is properly seated and not catching on the movement or housing.

Step 4: Double-Check the Alignment

After rotating the moon dial, advance the minute hand again to move the time forward a few hours. Make sure the dial begins to rotate slowly over time. If the moon is still at the top of the dial at midnight and the sun appears during the day, you’ve set it up correctly.

If it looks off, repeat the above steps and realign as needed. It may take a few days of observation to get it perfectly in sync.

How Often Do I Need to Adjust the Moon Dial?

The moon phase mechanism on the GMKIT2 is very accurate, but it works based on a 29.5-day cycle. Because a true lunar cycle is actually 29.53 days, you’ll need to adjust the moon dial by one day every two and a half years to keep it aligned with the actual moon phases.

That’s excellent accuracy for a mechanical clock, and it’s part of what makes the GMKIT2 a fantastic long-term investment for clock lovers.

Where Can I Get Replacement Parts or Help with the GMKIT2?

Everything you need to build and maintain your clock comes with the Westminster Grandmother Clock Kit GMKIT2. But if you ever need replacement parts—whether it’s a new moon dial, movement, or hands—we stock them all at Clockworks.com.

For customer support, you can also reach out directly through our contact page or give us a call. We’ve been working with clock kits like the GMKIT2 for decades, and we’re always happy to help.

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Why Choose the GMKIT2 from Clockworks?

The GMKIT2 isn’t just another clock kit—it’s a complete mechanical masterpiece. It includes:

Whether you’re building your first grandmother clock or restoring a family heirloom, this kit gives you everything you need—and the moon dial adds the perfect finishing touch.

Final Thoughts

Setting the moon dial on your Westminster Grandmother Clock Kit GMKIT2 is a small but satisfying part of the building process. By aligning the moon and sun images with the proper time of day, you bring your clock to life in a way that honors centuries of horological tradition.

Get your GMKIT2 clock kit here and experience the joy of crafting and owning a timepiece that connects the mechanical world with the celestial one.

Updated on: 14/07/2025

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