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DG3804B

abush

By abush
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abush New Member

abush

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Is there a proper way to remove a stem from a DG3804B so as not to booger the keyless works?.  I have removed movements before, replaced crystals and replaced hands and never had an issue with stems until now.

I was building my first GMT and was not able to get stem back in!  I had to rebuild the keyless works a real pain. I'm hesitant to try to remove stem again.

I think it should be in the 'hand setting' position and perhaps ever so gently press on the release until it just lets go. I'm guessing to much pressure allows the winding pinion to slide out of place.

Any advise perhaps Mark can do a video on this issue?   My current plan to to leave stem in, trim it, then use extended so as not to even remove the stem  (not best solution) just a real pain to fix the keyless works.

Thanks

Adam

manodeoro WRT Addict

manodeoro

Posted
Posted
5 hours ago, abush said:

Is there a proper way to remove a stem from a DG3804B so as not to booger the keyless works?.  I have removed movements before, replaced crystals and replaced hands and never had an issue with stems until now.

 I was building my first GMT and was not able to get stem back in!  I had to rebuild the keyless works a real pain. I'm hesitant to try to remove stem again.

 I think it should be in the 'hand setting' position and perhaps ever so gently press on the release until it just lets go. I'm guessing to much pressure allows the winding pinion to slide out of place.

Any advise perhaps Mark can do a video on this issue?   My current plan to to leave stem in, trim it, then use extended so as not to even remove the stem  (not best solution) just a real pain to fix the keyless works.

Thanks

Adam

I have dealed with some of those GMT movements and from my little experience :

- place stem in "hour setting" position

- press really gently on the release button (use the larger screwdriver that you can put there ... 1.5mm should do)

- turn gently (about 1 °) back and forth while gently pressing until it comes out

What we must consider is that DG3804B is (as far as I know) about just a DG2813 with a GMT function added ... so very low manufacturing quality and they are "hit or miss".

I have one which is a workhorse (almost) keeps pretty good time and never caused me any issue, and 2 which were just "shitty movements" until I decided to service them (long journey and much less easy than playing with an ETA).

I'm not certain that using an extension could be a good idea as the metal used for the wheels is not good so you'd better use the release button if you ever want to get the stem out ... just proceed really gently.

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manodeoro WRT Addict

manodeoro

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The keyless works is not that difficult on DG3804B movements ... just about the same as on DG2813, so the best is to train on those 3 hands movements.

That's what I did a few months ago ... removing keyless works and putting it back, even on perfectly working movements ... after some trials you can dismantle and put back really easily, even if thre is several variants of those movements.

When you can do that easily (almost) the only problem you have to deal on DG3804B is to not move or destroy the GMT gears and wheels while working on the keyless works.

But the best is to use other movements, japanese, swiss (or so called) or even high quality chinese (there are some) manufactured with higher tolerances.

abush New Member

abush

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Agree. My plan is to use an old one and just tear it all apart and play with it. resetting pinion is fairly simple now that I did it a few times..lol.  The first time it was a bit tricky getting the order of reassembly correct. Cheers!

manodeoro WRT Addict

manodeoro

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Agree. My plan is to use an old one and just tear it all apart and play with it. resetting pinion is fairly simple now that I did it a few times..lol.  The first time it was a bit tricky getting the order of reassembly correct. Cheers!
Each time I work on a new movement I take a pic for every part I remove ... It proves to be really helpfull while putting everything back together [emoji6]
Generally I start on the dial face (datewheel and gears, hour wheel, cannon pinion, keyless works, etc ...) then finish with the other face.
Of course the first thing I do is desarming the mainspring.

Envoyé de mon Moto G (5) Plus en utilisant Tapatalk

abush New Member

abush

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Weird. (this is not my movt) but when I put my keyless works in my dg3804b back together and inserted new stem it would wind and advance date perfect. However When in position 2 and I tried to set hands, the hands would start to move and then it was as if a gear slipped and no resistance. If I pushed stem back in and then out and tried again same result. I took it apart and noticed there seemed to be a lot of play in the gear in pointed to in the picture.  It was as if it would ride up on its pin. By some chance I had an old movt from years ago so I took it apart (it seemed to be very much like the dg3804b) and I grab another ever so slightly larger/taller gear replaced the offending one and presto it all works perfect now!  Not sure what the deal was with that but I'm pretty happy for now. Thanks!

sliding pinion and gear

  • 4 weeks later...
abush New Member

abush

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Well finished my first built.  DG3804 GMT movt, 40mm case, sapphire crystal, 28.5 dial and  carbon fiber strap. Ok so it cost me $120 but I got it all together myself! Plus learned how to fix keyless works priceless experience. Now looking a building something with a 6497.

dg3804watch.JPG

manodeoro WRT Addict

manodeoro

Posted
Posted
6 hours ago, abush said:

Well finished my first built.  DG3804 GMT movt, 40mm case, sapphire crystal, 28.5 dial and  carbon fiber strap. Ok so it cost me $120 but I got it all together myself! Plus learned how to fix keyless works priceless experience. Now looking a building something with a 6497.

dg3804watch.JPG

Really nice GMT... seems the datewheel has nice serifs ... congrats.

From my little experience (I have 3 of these) the DG3804B can be really reliable if you take care of it and it keeps the GMT hand pretty well synchronised.

Just take care of not changing the date or adjust the GMT hand after 10h00 PM and before 2:00 AM and you could keep it for years.

 

While building a watch with  a 6497 you'll see  that those "big" movements are pretty easy to work with, much more than DG2804Bs and DG2813s ... now waiting for your next thread ;)

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