Easy Seiko Mods You Can Do Without Disassembling Your Watch

It’s always impressive to see hyper customized mods that have some subtle or intricate detail on every part, but Seiko modding doesn’t always mean diving deep into the movement and messing with tiny gears and screws or 3D printing your own custom case. In fact, some of the most popular and eye-catching mods can be done without ever disassembling your watch. If you’re new to the world of Seiko mods or just not ready to fully tear down your timepiece, we’ve got some easy suggestions that might be the perfect place to start.

In this guide, we’ll walk you through a few beginner-friendly mods that anyone can do at home with the right tools and a little patience. These upgrades are easy, affordable, and can totally change the look and feel of your watch. Think of it like giving your favorite sneakers a fresh pair of laces, or swapping your phone case for something that actually matches your style.

Let’s get into it: here are some easy Seiko mods that don’t require completely disassembling your watch.

 

Strap or Bracelet Swap

 

This is hands-down the easiest and fastest mod you can do, and is usually something that even non–Seiko modders like to do. Swapping your strap or bracelet takes just a few minutes, but the effect it has on your watch’s style and comfort will certainly be noticeable. You don’t need to open the case, mess with the movement, or do anything complicated. Just switch out the old strap for something that better fits your style, the season, or the occasion.

You’ll typically need a spring bar tool to swap straps, but if your strap has quick-release tabs, you can skip the tools and just pull and swap. When choosing a new strap or bracelet, make sure you get the right lug width. The most common sizes are 20mm and 22mm, but there are some odd sizes (like our NMK940 GS Dress Case with 19mm lugs) so double check your specs. From there, it’s all about style and comfort: go with FKM rubber for a sporty, durable feel, a NATO strap for that rugged, military look, leather for casual everyday wear, or stainless steel for a more premium and versatile finish. Don’t forget to play with color and texture too!

Swapping straps is a fun way to refresh your watch without spending a lot of money. It’s also a great way to make one watch feel like five different ones.

Bezel and Bezel Insert Swap

 

If you’re ready to level up from strap swaps, changing the bezel and bezel insert is your next best move. It might sound a little more advanced, but don’t worry since you won’t need to crack open the watch or touch the movement. Beware though, this is how Seiko modders usually get sucked into the hobby!

The bezel is the metal ring that sits around your watch crystal, and the insert is the decorative (and often functional) ring inside it, usually marked with minute/hour markers or dual time indicator for GMT’s. Swapping them out can completely change the vibe of your watch from dive-ready to vintage-inspired, to stealthy and modern.

There are tons of insert styles out there! There’s ceramic for that glossy, high-end feel, aluminum for a classic look, or even lumed inserts for continued functionality in the dark. Just make sure the bezel and insert are compatible with your watch model (SKX007, SRPD, etc.).

If you need more information about how to choose your new bezel and insert, and how to do the swap, we cover them in-depth in this article.

Caseback and Rotor Swap

We’re getting into the good stuff now! While the process of replacing the caseback itself is quite easy (you just unscrew the old one and screw in the new one), this one will need a bit more confidence as you will possibly be altering the water resistance of your watch.

The most common replacement option that we see is changing from the regular caseback to a slim one - shaving off a few millimeters from the thickness of a watch and improving its stance and overall wearing comfort. Doing so usually reduces the WR rating of a watch from 200m to 100m - a compromise that many are willing to take since most watches aren’t being taken to actual deep sea dives anyway.

If you’re feeling a bit brave, a rotor swap is something that’s really going to give bling to your watch, even if you keep everything else OEM. The rotor is the metal disc on the back of your movement that rotates to wind up the watch when you move your hand. The stock one on NH movements is a rather boring piece of metal. What if you swap that with a Clous De Paris rotor for a classic luxury look, or a golden Asanoha-patterned rotor for a Japan-coded aesthetic? Together with a new rotor, you’ll want to swap to a sapphire display caseback, unless you’re going for an easter egg-like mod. 

Just be gentle when working near the movement, and make sure everything is clean before sealing it back up.

This is going to be a lot trickier than the other part swaps, learn more about rotor swaps in this article.

Bonus: Crown Swap

 

If you’re already popping off the caseback to change the rotor, upgrading the crown is a smart add-on that can improve both function and style. Aftermarket crowns can offer better grip, a cleaner design, or even upgraded water resistance (like with our triple gasketed crowns). Some also come with engraved logos or colored accents for that extra custom touch.

Modders usually like to match the pattern on the crown and bezel. In our store, some of the matching patterns on crowns and bezels are knurled (criss-crossing pattern), chunky (larger indents), and coin edge (narrower indents). We also have S-signed crowns and sterile ones to suit your Seiko mod.

Quick tip: Make sure the crown is compatible with your movement (like NH35 or NH36), and if you're changing the stem length, measure carefully and incrementally shave off the excess length instead of snipping off large parts off your crown stem.

 

Wrap Up

Don't let Seiko modding scare you off! You don't need to take your whole watch apart to make awesome changes. Start small with your strap swaps and move your way up to more complex mods as your confidence grows. Each step is easier than you might think!

Every watch lover started as a beginner. These simple mods are a great way to dip your toes into watch customization. The best part? Seeing your personal style on your wrist every day.

If you want to learn more, you can check out our Modding Guide 101 for more easy-to-follow tips. And when you're feeling inspired, visit our store to find the perfect parts for your Seiko mod. 

Happy modding!