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Eta 7750 Service Walkthrough - The Industry Standard Chronograph


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  • 6 months later...

Walkthroughs not only help others but they also help the person doing it by allowing him/her some time to reflect in a) what it has been done, B) what is has been discovered on that particular instance and c) by explaining something we are supposed to know...It is said that if a person doesn't understand something he/she can't explain it. So, there you have it, by helping others -- in the form of sharing knowledge -- we also help ourselves, one way or another...or what goes around comes around!

 

I could also say that one way to approach perfection on anything is to teach that subject. It is also the principle in martial arts and many other disciplines -- and I believe is the traditional way to teach in the Eastern Countries, but correct me if I'm wrong about this. I do know that in martial arts higher belts are supposed to teach lower belts, that way they also learn, remember and get better at it.

 

Just my two cents on this...Lawson, buddy, your walkthroughs are awesome we miss them!

 

Cheers,

 

Bob

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  • 1 month later...
On 25/06/2015 at 2:37 AM, sstakoff said:

Hi. Curious as to the group's view on how essential the Fixodrop/8941 treatment is for a 7750 servicing???

Hi sstakoff,

Sorry I missed this question mate, please forgive me ... and I agree with Scottster that it is an excellent question indeed.

Fixodrop makes oils stay put, and for this movement with lots of parts moving closely to one another it's highly recommended.  Remember, your job as a watch repair is to ensure that the time piece functions flawlessly between services ... that's 5-7 years!!  The recommendation of Fixodrop is to keep the lubrication exactly where it is needed for it's service life.

It also makes your oiling work look very neat and tidy.  Remember guys, lots of these movements have a display back, and your workmanship is on show for years.  I personally love the stuff, and use it on all end-cap jewels.  Plus, one bottle at home will last you approximately 20 million years (give or take a decade) ^_^ as the bottle is HUGE.

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  • 4 weeks later...
On April 16, 2016 at 2:05 PM, Lawson said:

Hi sstakoff,

Sorry I missed this question mate, please forgive me ... and I agree with Scottster that it is an excellent question indeed.

Fixodrop makes oils stay put, and for this movement with lots of parts moving closely to one another it's highly recommended.  Remember, your job as a watch repair is to ensure that the time piece functions flawlessly between services ... that's 5-7 years!!  The recommendation of Fixodrop is to keep the lubrication exactly where it is needed for it's service life.

It also makes your oiling work look very neat and tidy.  Remember guys, lots of these movements have a display back, and your workmanship is on show for years.  I personally love the stuff, and use it on all end-cap jewels.  Plus, one bottle at home will last you approximately 20 million years (give or take a decade) ^_^ as the bottle is HUGE.

Thanks for the expaination. When you say you use it on all end-cap jewels do you just soak them in Fixodrop and and apply 9010 as usual? How does the oil stay in the middle of the end-cap jewel if it is coated with Fixodrop?

Thanks ahead of time. 

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49 minutes ago, Scottster said:

When you say you use it on all end-cap jewels do you just soak them in Fixodrop and and apply 9010 as usual? How does the oil stay in the middle of the end-cap jewel if it is coated with Fixodrop?

Thanks ahead of time. 

The proper way to apply Fix-o-drop is with a  Epilane Bottle as pictured below:

Epilane Bottle.jpg

The lower part of the bottle is filled with Fix-o-drop (to the blue line), and the items you wish to treat with the product go into the white basket.  Then you affix he lid and flip the bottle upside down, coating the product on all the parts in the basket.  When the parts are remove the Fix-o-drop evaporates rapidly leaving a coating that holds the oils in place.

Unfortunately the asking price for these bottles is pretty steep, and I don't own one at present.  I just dip a cotton bud in the Fix-o-drop and dab in on the incabloc jewels ... it's crude, but effective - and until I can find an Epilane Bottle as a reasonable price it's the way I do it.

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31 minutes ago, Scottster said:

Yes. That little bottle sells for $169.00 USD. 

 

This one sells for $18.00 USD from Otto Frei. 

Thanks for the info. I'll give it a try. 

Is Fix-o-drop the same as Lubeta v105?

JC

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5 minutes ago, Lawson said:

Hey JC,

No mate, V105 is a lubricate for automatic reversing wheels

Ah OK. I bought lubeta based on your recommendation for valjoux 7750 and it's great. I thought I'd get more use out of it, but I'll check out fix-o-drop. Thanks for the great 7750 walk-through by the way. I'll be posting when I'm done.

JC

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  • 1 month later...

Hello!

If I may, I'd like to ask the admin to update the links. Lawson uploaded two docs (assambly and disassembly of 7750). Also other users also posted some documents which cannot be downloaded.

Thank you,

Bogdan

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  • 1 month later...

Hi Den,

The walkthroughs are the actual work of our members, who have done a great contribution of time and resources to all of us. I take the opportunity to say thank you to all of them.

Any member is welcome to post their own and they don't have to be as detailed or for such an in depth subjects as Lawson's but the more details the superior the walkthrough and the more we all learn from one another. All efforts are greatly appreciated.

Cheers,

Bob

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I used Lawson's walkthrough snd was able to succesfully overhaul a 7750...I did it in sections across one week. I also used ETA's on-linr resource for the

maintenance of the 7750, which is excellent.

J

Sent from my SM-G925T using Tapatalk

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  • 2 months later...
  • 3 months later...

Hi Matabog,

I don't believe so mate.  If that where the case then you would have to VERY carefully mark which one is what as you are disassembling the movement, because they look exactly the same ... and I have never done this.  They also do their function at the same time of the day, so there can be no variation in the tooth count.

Please guys, if I am wrong let me know, we are all here to learn and I could be mistaken.

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Looks like the drawing supplied is not correct. I wish I had seen that vid. However two components that really do look alike but are not are these. I got them mixed & as a result the calendar date wheel did not always centre in it's window. 

 

58b7ccf3859ca_ScreenShot2017-03-02at07_42_12.png.0b3ba929954e3e3a146bf8e325dc2f38.png

 

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  • 3 weeks later...
  • 10 months later...

I am by no means a Certified or Professional Horologist.  But I have had a passion for Time from the age of 8.  I have broken and rebuilt many timepieces but this was an ABSOLUTE life saver!!  I was able to use the tutorial, highlights and parts catalog to rebuild a FORTIS B42 Chronograph and bring it back into action.  Thank you for the excellent job and assistance.

Attached are some of my progress photos

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