NH36A

The NH36A is a mechanical watch movement developed by Seiko. Its complications include sweeping seconds, seconds hacking, a date display, a day-of-the-week display, and automatic winding.

Here you see the watch mechanism (left), the bezel insert (top), the watch case (bottom), and the watch dial and hands (right)

Here the bezel insert has been attached to the watch case. The bezel can rotate around the face of the watch, allowing you to see the time in other time zones at a glance (more on this later). Also: note that you can see all the way thru the case. This is because there is a glass back, allowing you to see the mechanics of the watch.

Here we see the back of the watch movement in a movement holder. The half circle covering the bottom half of the movement is the automatic winding rotor, on which “NH36A” “Twenty-Four Jewels”, and “TMI” is written. Jewels refer to the artificial rubies that are used as baring surfaces in the watch, one of which can be seen just above the right side of the rotor.

At this point I have already attached the dial to the watch movement. Some dials are attached with screws in the side of the movement, but on this model of watch there is simply an interference fit between the dial feet and the movement. Here you can clearly see the 月 kanji in the day-of-the-week window. I got this particular movement because it has the days in Japanese.

Here the movement has been put into the case. I trimmed the stem down to size so that the crown was able to screw down properly. It was here that I realized that the time zone bezel required either a 24 hour movement or a GMT complication. I could have chosen to live with the issue, but instead I took it as an excuse to get a new movement for this case and a new case for this movement.

Just because I’m going to switch out the movement doesn’t mean I didn’t get a band to wear it around.

Addendum 1: my NH34 movement came, so I de-cased the NH36 and it is now living safely in a box until its new case arrives.

Addendum 2: The new case arrived, so it’s time to put the NH36 inside!

Step 1 when using this kind of watch band was to remove one of the spring bars to expose the back of the case.

Then it was just a matter of unscrewing the back and dropping the movement in. Notice however that the stem is too long for this case, so I had to trim and file it down to size to fit.

The bracelet as it arrived was a bit too loose for my liking, but the pins inside the links would not budge (notice the broken punches), so I have no choice but to leave it as is for now.

The watch re-cased.

Addendum 3: To say that I assumed that the bracelet was held together with cotter pins would be an understatement. I did not know that there was an alternative to cotter pins. This to say, the reason I could not remove the pins from the watch was because they were screwed in. So, I removed a link and now the watch fits me better.