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Replace a complete balance wheel and bridge for ETA 2804-2


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Hi all,

I broke the pivot of balance wheel on ETA 2804-2.

I bought a generic complete balance wheel with bridge for ETA 2824-2 (http://www.ebay.com/itm/262234041099?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT) and tried to install it without any difficulty. There is only a difference between the new and old one is the shock assemblies (Incabloc vs Novodiac). In the photo below, the new one is the yeallow on the right hand side.

IMG_1540.thumb.JPG.432f53ea73f6cbf86f776996c6068e68.JPG

My question are:

- Is the complete balance wheel and bridge replaceable between those movements?

- If Yes, after installed, the balance wheel has swung a little bit then stop. What is the reason? How to fix it?

Thank you

 

Edited by hokavan
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try using only the balance complete (balance wheel and Hairspring) - meaning use the old cock and the new balance complete.

It looks to me like you don't have enough end-shakeand a cause would be the different shocks (Incabloc and Novodiac)

To take it off:

 

Edited by matabog
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It looks like the balance roller jewel is not engaged with the pallet folk correctly. It might be a mile out of beat so it will be worth removing the pallet folk & bridge and rotate the balance & check that the roller jewel settles in the middle of the banking pins.

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  • 2 weeks later...
Doesn't look like you got the balance in the right position? Make sure that you have the roller jewels inside the pallet fork.  Which i don't you have right. Maybe that is why you broke the last pivot. 

Yes you are right. The roller was not in right position.


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try using only the balance complete (balance wheel and Hairspring) - meaning use the old cock and the new balance complete.
It looks to me like you don't have enough end-shakeand a cause would be the different shocks (Incabloc and Novodiac)
To take it off:
 

I don't have tools to remove the balance and install it on the old bridge. It could be the end- shake problems because if I pressed down the end of bridge it would run faster.
I was looking for complete balance and bridge for ETA 2804 but was unable to find it. Could you please suggest any other way to fix it?


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  • 2 years later...

The balance and bridge on the left is for a 2824-1 and the one one the right is a 2824-2 balance.

These are NOT compatible because they run at different rates.

The 2824-1 runs at 21600 both and the 2824-2 runs at 28800 bph so you CANNOT interchange them.

Even if it were possible the timekeeping would be hours per day out 

Get the correct balance.

Regards

James

 

  • Thanks 1
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10 minutes ago, Horologist said:

Get the correct balance.

Correct, but you're replying to an almost three year old topic, one would suppose the issue has been sorted out by now.

Also, FYI we have a dedicated section of the forum where is considered polite for new members to introduce themselves.

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  • 1 year later...
On 2/28/2020 at 1:24 PM, jdm said:

Correct, but you're replying to an almost three year old topic, one would suppose the issue has been sorted out by now.

Does it really matter? I found the provided info extremely interesting. @Horologist wrote his first and only post the same day he joined, six month ago, and we haven't seen him/her here since. I wonder why. Any idea?

Edited by VWatchie
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