🔧 How to build a NH71.5 custom watch movement
🛠 How to Build a Custom Seiko Movement with NH71 & NH72 Parts (Golden Detail Mod)
🔧 Why Combine NH71 and NH72?
If you're deep into the world of Seiko modding, especially skeleton builds, you’ve likely come across the NH70 series—a family of open-heart and skeletonized movements ideal for showing off your custom dial work. Two of the most visually striking are the NH71 (gold-tone skeleton) and the NH72 (gunmetal skeleton).
But what if you could get the best of both worlds?
In this guide, we’ll show you how to strip and rebuild a hybrid movement by combining parts from the NH71 and NH72 to create a stunning Seiko skeleton mod movement with golden details—ideal for your next Royal Oak mod, Seikoak, or custom timepiece.
🧰 What You'll Need
Movements:
⚙️ Shop Seiko NH72 – The gunmetal NH72 is the perfect base for a hybrid skeleton movement.
Buy the NH72 movement →
⚙️ Shop Seiko NH71 – A high quality golden skeleton movement you can use for parts to add beautiful golden accents to your gunmetal NH72 movement.
Buy the NH71 golden movement →
Tools:
-
Loupe or microscope
-
Movement holder
-
Hand remover & installer
-
Plastic tweezers
-
Small screwdrivers (Seiko/ETA size)
-
Finger cots or gloves
-
Rodico or similar cleaning putty
Optional:
-
Oil and oiler for light lubrication
-
Dust blower
-
Lint-free cloth
⚙️ Step-by-Step: Rebuilding Your Custom Skeleton Movement
Step 1: Prepare a Clean Work Surface
Dust is your enemy. Lay down a microfiber mat or use an anti-static watchmaking pad. Make sure your lighting is even and bright.
Step 2: Disassemble the NH71
-
Place the NH71 in your movement holder.
-
Remove the hands (if pre-installed) and gently lift the dial off.
-
Carefully unscrew and set aside the gold balance cock, gold skeleton bridges, and gold-colored gear train parts. These are your hero components.
Tip: Handle all golden parts with plastic tweezers to avoid scratches or tarnishing.
Step 3: Strip Down the NH72
-
Now do the same with your NH72 movement.
-
Remove and set aside the gunmetal base plate, main bridge, and main gear train components.
-
These will serve as the foundation for your hybrid build.
Step 4: Combine Key Parts
-
Begin installing the NH71 gold bridges and select gear train parts onto the NH72 gunmetal base.
-
This creates a contrasted hybrid Seiko movement, where gold pops against a darker skeletonized base.
Common golden detail swaps include:
-
Gold escapement wheel
-
Gold center wheel and fourth wheel
-
Gold skeleton rotor (optional if using NH71 automatic rotor)
Step 5: Lubricate and Reassemble
-
Apply light oil to pivots and jewels as needed.
-
Reinstall bridges, then test wheel rotation.
-
Reinstall dial and hands once you're confident the gear train spins freely and the escapement ticks.
🎨 Why This Mod Looks Incredible
Using this technique, your movement now features:
-
A gunmetal skeleton base with selective golden highlights
-
Unique contrast that looks luxurious and custom-made
-
Perfect pairing for gold skeleton dials, smoked sapphire backs, or open-back Royal Oak-style builds
It’s ideal for anyone building Seiko mod skeleton watches with a focus on luxury detail—especially when pairing with mod cases like the Royal Oak 37mm Seiko mod case or custom brushed watch cases.
🔗 Recommended Parts for Your Build
Shop the Parts You Need:
✅ Final Tips for a Clean Build
-
Always test your movement in a timegrapher after rebuild.
-
If you're new to movement building, consider practicing on spare NH35s before working with skeleton calibers.
📦 Ready to Build?
Get inspired, get building, and share your final result!
Tag us on Instagram @nomods.co with your #NH71NH72Mod creations.
Let me know if you want a second variant of this blog post to avoid duplicate content or if you’d like Shopify-optimized image alt texts and filenames to pair with this post.
