Rebuilding a GMT 2

[GenTLe]

What below represent the job I did this week evenings. I started last Mon or Tua and finished today. All condensed into one single post.

I recently got a Noob GMT 2 kit from themannier here on RWG. It was complete except for the DWO and 3 of the 4 parts that turn a standard 2836 into a GMT. Plus it was completely disassembled.

Going to show the rebuild process.

First I unassembled the movement (and it is when I discovered that the GMT parts have been replaced with standard ones, except for the gmt hand gear/pinion) and properly washed it.

Here after first rinse:

And second rinse (between the temporary allocation over lint free paper and the passage in the 50°C oven I use to dry them):

In the meantime I got a brand new BK dwo from USA that I will glue over the naked date wheel.

Here you can see what transform a standard 2836 into a GMT version, together with the higher cannon pinion:

Below the GMT bits, upper the standard ones.

Here together with movement partially assembled:

Finished (missing only the GMT hand gear and the BK DW overlay which will be done when I will be fresher than like now ar 11pm):

Definitively not bad for a movement not yet regulated! Lovely amplitude and 0 beat error

This eve I have installed and glued the dwo that BK has been so nice to sell me on the naked date wheel.

Here you can see the result. For the alignment (that I have obviously checked) pictures we need to wait tomorrow.

The glue I've used is in the pic.

It has 2 big advantages respect to the others:

1) when it's dried it keeps 300kg/cm2, this means that I can use a VERY little amount of it, placed with an oiler on just 4 points of the DW. This will avoid it spreading around ending up on the movement and/or the DWO.

2) this glue fully dries in 12h and if you put a low amount of hardener it remains very soft for more than 1h (at least for more I needed to align properly the DWO). This means precious time to use for alignment!

Plus I used that glue to fix a magnet of the flying wheel of my motorcycle, and after 20kkm spinning up to 12000rpm in hot oil and with the V-twin pulses the magnet is still there

Check of DWO alignment: love it!!

Hands alignment done!

In the case:

I also leaned something today: if your movement is performing amazingly half assembled and, after casing, it starts to behave erratically with ridiculous amplitude (197°) and very inconsistent gain/delay, then check the sec hand! Mine was nearly touching the crystal and it was causing this stupid behavior

Once I pressed it a little bit more into its pinion it went back straight to the results of the pic:)

Ok so how to relax oh a Sunday afternoon after a good MotoGP race (even if it has been very sad for Rossi...)? Move on with the GMT is a good idea

Since the watch has been bought in bits and I don't know the story behind apart being it a Noob, a good idea is to remove the bezel and give a good clean to its parts:

That way I will also be able to give a repolish to the surfaces without messing up with the bezel mechanics.

Lubricating the bezel assembly with oil or grease isn't a wise move, because in some time they will end up in a kind of dirty paste as oily materials attract dust and incorporate it in the lubricants.

So I used my dry Teflon spray, spraying it in a bowl and using a brush to apply it.

When the solvent will be evaporated, it will just leave a thin layer of dry Teflon on the surfaces, reducing a lot the friction.

Then some attention to the bracelet. Rebrushed and repolished where needed:

Then a good clean in the ultrasonic machine, rinse with hot water and remount/resize it.

And finally:

Kind of happy of the result

[Mendota Explorer]

Very nice!

Sent from my SM-N920P using Tapatalk

[imajedi]

Really incredible job. So impressive.

[GenTLe]

Thanks guys

[freddy333]

Great write up. Well done.

[dutchguy2]

1 hour ago, freddy333 said:

Great write up. Well done.

+1

 

[997 s]

Nice work