Heads Up Advice Wanted before Opening GMT Case

[ETonePJ]

I have wanted to look inside my GMT 1675 for quite sometime. I've resisted that inclination, until now, because I would always recall my dad telling me, "only two kinds of people open a watch, watchmakers and fools."
But now, having owned this watch for 40 years, I would like to open it up.
I have two reasons for wanting to do this. 1) I'd like to see the inner-workings of my watch; 2) I hope to find any service markings that would tell me if my dad had gotten service on it before he gave it to me.

So, I purchased a Bergeon ball. I have used this to open a Seiko 6139, and a fake Rolex I got in Thailand nearly 40 years ago. Same kind of caseback, and the ball opened it fine (and it was resistant due to oxidation in the threads).

While I now have the means, I want to make certain I consider any precautions to prevent contamination or damage during opening and closing.

Any advice will be greatly appreciated.

[Tools]

Contamination is possible if the inside of the threads etc, are corroded. Crack it a bit then brush or blow around the threads before taking it all the way off.

Also it's hard to actually break anything unless you drop it while doing the operation.

The tricky part is getting it back together. Might need a new gasket, maybe not, likely def needs lube. Then you need to ensure it is on straight and tightened to an appropriate torque.

[77T]

Your Dad was a wise one...

Wear finger cots or nitrile, wear a filter mask, and buy an air duster bulb to blow away lint before closing it up.

https://www.amazon.com/gp/product/B0...s%2C97&sr=8-3#


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[ETonePJ]

Thanks guys. Each of you brought up things I hadn't considered. I'll think on this some more.

[capice]

open it in the bathroom, where you brush your teeth, not the other one...that has the least amount of dust flying around

[brandrea]

The other option might be to take it to a watchmaker nearby.

At the very least, they may have some more practical experience and they could let you inspect the movement and see if there are any markings

[77T]

Originally Posted by capice

open it in the bathroom, where you brush your teeth, not the other one...that has the least amount of dust flying around

Never do watchmaking in a bathroom.

Dust is the least perhaps, but the bathroom is the most common place for mold spores.

Mold would be more concerning than a speck of dust methinks.


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[77T]

Originally Posted by brandrea

The other option might be to take it to a watchmaker nearby.

At the very least, they may have some more practical experience and they could let you inspect the movement and see if there are any markings

^^^

Ya think?


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[brandrea]

Originally Posted by 77T

^^^

Ya think?


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Well this is coming from a guy who can’t change a bracelet without spring bars flying across the room


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[77T]

Then there's this...

https://youtu.be/oPkPXmrDUt0?si=sfdOMgwpzPPy7wCi