Seiko SKX007 - DIY Modding

May 06, 2024


I recently had the thrill of acquiring the legendary Seiko SKX007. Purchasing it from a local seller in the aftermarket, I couldn't believe my luck when I saw the price listed at just €150. Without hesitation, I made the offer and secured the deal, despite the absence of the original box and package.

Soon I brought it back home, I started off with a timekeeping issue - my SKX007 was running way too fast, like 10 seconds ahead per minute fast. After some failed attempts to fix it, including trying to calibrate and demagnetize it, I decided to swap out the movement myself.

skx007 and the nh35

SKX007 and NH35 Movement

I ordered all the parts and tools online and got to work. The new movement is NH35 with a Japanese daywheel because it makes it look more Japanese. And an AR coated sapphire crystal was ordered for replacing the original scratched hardlex glass crystal. The disassembly went pretty smoothly, but things got a bit dicey when it came time to put the minute and second hands back on. Long story short, I ended up with a few scratches on the dial. Oops.


Placing secondhand

But hey, I wasn't about to let a few scratches get me down. I embraced them as part of the journey and moved forward. Or so I thought. Just when I thought I was in the clear, disaster struck – the stem broke inside the crown as I was trying to set the time. Major setback, right?

I had to order another crown replacement, which took another agonizing half month to arrive. But finally, after what felt like an eternity of waiting, I got the new crown installed and everything up and running. Phew!


Completion - running smoothly

And I almost forgot - somewhere along the way, I also decided to swap out the original Hardlex glass for a sapphire crystal. It took a bit of extra effort, but the added scratch resistance were well worth it and the doomed crystal looks really cool.

In the end, I believe it's all worth it when I see my skx ticking away perfectly (within the specification of NH35) with few minor scratches I caused personally.