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Posted

Many things have interrupted my learning process but I finally got into taking apart my eta 2750 movement. Didn't get very far. To train myself using tweezers I removed and installed the wheel bridge screws about 20 times. Everything went well so I removed the wheel bridge and did inspection so I memorize each component so far. I then tried to reinstall the bridge, it didn't pop back into place like the many pocket watch bridges I dealt with earlier.

I'm being very gentle trying to move the bridge around to feel when the pivots pop into the hole jewels but it doesn't seem to be working. Its getting late and I will try tomorrow.

 

Is there a sequence to which pivots get installed first? Or just keep practicing?

 

Al

Posted

Hey Al! Glad to hear from you and it was outstanding to see you doing your thing at the NAWCC on Nov 9th. so thanks for that opportunity. I've not worked on an ETA 2750 but I looked it up and see it is a big bridge with 4 pivots to line up. I've done so many watches now that I can tell you that it is just a matter of placing the bridge right atop the screw holes as a rough guide, and then gently moving the bridge with brass tweezers until you feel the pivots--or at least one, go into place. Foe me the most difficult one is always the escape wheel pivot. That one takes gentle prodding from under the bridge and sometimes spinning the drive gears a little bit with the tweezers helps, and then they all fall into place. I've done both cheap watches where its a breeze to line up the pivots on the top plate (there usually is no bridge) to better watches with separate bridges where is hard to make them line up. It takes a little practice, and if I get frustrated I put it away for some other time. One thing I have learned to do is never tighten the screws up on a plate until I have confirmed with a 10x loop the every single pivot is in its place and also by giving the drive gears a little push with  brass tweezers--only when they are freely spinning do I begin to tighten and I recheck to make sure the gears are properly seated and spinning before giving the final tightening. You just keep nudging the bridge around and pushing gently down with brass tweezers, then look with a 10x loop to confirm if you need too. This is what works for me. Keep practicing buddy!

 

JC

  • Like 1
Posted

Hi Joe, it was good to meet you too

 

Thanks for the advice, I'll proceed tomorrow with a fresh start. With pocket watches I never had a problem. so I think all will fall into place with a little, a lot, of patience.

 

If you feel like talking about watches in any respect in front of a group, contact Chapter 2, they are always looking for new speakers on many subjects of Horology.

 

Al

Posted

Hi Al,

As a newbie to watch repair, I have personally found this to be the most difficult part of a full tear down, cleaning and reassembly.  Patience is the key and not allowing yourself to get frustrated.  I've learned to chuckle when the pivots don't line up (for the 113th time!) rather than blowing a gasket or popping a vein.   Just so know you're not alone, here's a post I made recently regarding this issue. http://www.watchrepairtalk.com/topic/694-st96-restoration-walkthrough/page-2?hl=%2Baligning+%2Bpivots#entry9387

Cheers!

Roger 

Posted

Swearing also helps Al, believe me, at some point you will need to blow out steam if it gets really bad...you know there are those days when no matter what we do it won't happen! So, don't worry and as everybody is saying, patience and more patience!

 

Cheers,

 

Bob

  • Like 1
Posted

Well Guys, the operation was a success but the surgeon almost died.

 

I took your advice and used common sense and patience.

Since I knew I did something wrong, I took out the Balance assembly, the lever and its bridge, all the train wheels and the gear on the spring barrel. I did this to make visible room so I could see how each wheel likes to go into its pivot holes

It amazing how delicate this stuff is compared to clocks. I'm glad there are no stop, warning wheels or auto correct mechanisms to setup

I installed all the wheels and gear in the proper order, Installed the Lever bridge which gave me a little fight. The balance wheel just dropped in first time. put a little tension on the MS and it began escaping with a quarter turn of winding.

 

Everything went too easy so I'm going to reassemble several times to bond with this movement.

Thanks guys for your advice, not to give up and take my time

 

Al

Posted

Congratulations Al now you have gone full circle! From the watch on your wrist to fixing clocks to fix the watch on your wrist, isn't that something! It is a patience deal and a rewarding "job"!

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