Homage Forum

I have not had time to post lately but did complete these two MM300 builds. Thanks to @Aikidosan & @big eebee on these builds.

The first is a Crystaltimes MM300 case. I am really impressed with the parts from Crystaltimes. That look great and everything went together smoothly. It is all based on SKX parts. It was nice to be able to mix and match. I used a Seiko LX style ceramic insert and Grand Seiko hands. The dial is awesome. It is from Komoworks, the Seigaina waves give it a ton of depth. Lastly it uses the new Seiko GMT movement. I like having the GMT hand but dive bezel. I use the dive bezel much more frequently. The bezel insert is narrower than traditional MM300, this makes it very wearable.

The second is a franken titanium MM300. The titanium on the case is great (it is now made out of unobtanium). It is polished like stainless steel but lighter. I think it is a higher grade. The bracelet is the normal titanium we are familiar with. The dial is OEM Seiko SBDX017, this was the first series MM300. The lume is great. Seiko hand applied the lume and it looks a creamy white in person. The chapter ring is a OEM SBDX. I added the black date wheel. Also, the strap came with a Seiko ratcheting clasp. This is the first time I have used a ratchet clasp. I now want to change all my metal bracelet to this type of clasp. I also purchase a gen bezel click "washer" to replace the click spring. It fits perfect on the case, but the teeth do not line up with the bezel. I went back to the click spring.

I liked both cases, therefore tried to use quality parts. I am happy with the end results.

Sorry if pics are too big. I always have a had time with deciding on the proper size.

Very cool!
They both look awesome.

One question. I thought the new GMT is thicker than the NH25. Did the GMT movement fit into the case without problem or did you have to mod something?

Glad they came together as well as they did. And yes , the gen ratcheting clasp is a must have upgrade, especially on a titanium case

Looks fantastic and thanks for the cameo appearance

@hako the gmt movement (NH34) and traditional nh35 movement are the same dimensions.

The difference is in the hand pinion height. The gmt height is the same as the nh35 high hand stack. Total height 7.58mm vs 7.98mm. It is 0.4mm taller.

So the gmt movement will fit all cases but second hand pinion might hit crystal on shallow builds. I gave it a shot figuring a mm300 case with slight domed crystal would work. It had no issues. A dress watch case might be a problem.

I did have to broach the dial hole to fit the wider gmt pinion. Also, I had to fabricate a wide hole hand setting tool. I could not fit one that fit the wide gmt hand. I hollowed out a wooden dowel rod.

Thx for this info. I had in mind that sth essential was different between those movements, but confused thickness of it with the height it needs for its hands.
But good to know that your config works. This will give many new options for a true GMT MM300