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Refit balance


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16 minutes ago, RichardHarris123 said:

I'm struggling to refit a balance.  Looked up and followed advice from here but no matter which way I try the balance doesn't swing.  Been trying for a good hour or more now. 

You should take a break first. I’ve found that things in watchmaking rarely work out well if you spend too long on it and there’s still no improvements. Two hairsprings that I have ruined will agree with me.

Anyway, after you have taken a break, here’s a couple of things to consider. Have you given the movement a bit of wind, and the pallet fork snaps cleanly from one side to the other if gently prodded? Before you placed the balance cock, which direction was the pallet fork pointing? I normally have the pallet fork horns pointing in toward the middle of the movement. Next, upon placing the balance cock, have you visually sighted that the lower balance pivot is sitting in the lower pivot jewel? If you have seen that the lower balance pivot is safely in the lower shock block, is the upper balance pivot in the upper shock block? The upper balance pivot is more difficult to visually sight, so I normally have the upper balance jewels removed, but this is not always necessary. If the balance is still not moving freely,  I will take off the balance cock, and move the pallet fork to the other position.

Finally, if the movement is a hacking movement, do ensure that the winding stem is in the winding position, if not the balance will not be swinging due to the hacking lever.

Edited by ifibrin
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34 minutes ago, ifibrin said:

You should take a break first. I’ve found that things in watchmaking rarely work out well if you spend too long on it and there’s still no improvements. Two hairsprings that I have ruined will agree with me.

Anyway, after you have taken a break, here’s a couple of things to consider. Have you given the movement a bit of wind, and the pallet fork snaps cleanly from one side to the other if gently prodded? Before you placed the balance cock, which direction was the pallet fork pointing? I normally have the pallet fork horns pointing in toward the middle of the movement. Next, upon placing the balance cock, have you visually sighted that the lower balance pivot is sitting in the lower pivot jewel? If you have seen that the lower balance pivot is safely in the lower shock block, is the upper balance pivot in the upper shock block? The upper balance pivot is more difficult to visually sight, so I normally have the upper balance jewels removed, but this is not always necessary. If the balance is still not moving freely,  I will take off the balance cock, and move the pallet fork to the other position.

Finally, if the movement is a hacking movement, do ensure that the winding stem is in the winding position, if not the balance will not be swinging due to the hacking lever.

The balance will move freely in one direction but not the other.  Have I got the impulse jewel on the wrong side  

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3 minutes ago, RichardHarris123 said:

The balance will move freely in one direction but not the other.  Have I got the impulse jewel on the wrong side  

Yes, it's outside of the horns. Undo the balance cock screw a bit, raise the balace cock a bit and it should go in place almost by itself. 

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10 minutes ago, RichardHarris123 said:

It didn't work, how do I get it inside the horns. 

Depending on how you place the balance wheel (and balance cock into the movement), you have to ensure that the direction from which you rotate the balance cock into position has the impulse jewel in the right orientation relative to the fork horn. You can place the balance wheel into the movement the same way you did previously, but with the pallet fork facing the other direction.

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I struggled with this at first, but once you get the technique, it's easy.

I push the pallet fork towards the centre of movement. Hold the balance cock outside the mainplate at 90 deg to the movement. This ensures that the impulse jewel will be beyond the fork.

Move the cock in towards the mainplate and locate the lower pivot in the jewel. Then rotate the cock round to it's final position.

See how Mark does it in this video, (16m 45s)

https://www.youtube.com/watch?v=7bzU816kO-Q

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25 minutes ago, ifibrin said:

Depending on how you place the balance wheel (and balance cock into the movement), you have to ensure that the direction from which you rotate the balance cock into position has the impulse jewel in the right orientation relative to the fork horn. You can place the balance wheel into the movement the same way you did previously, but with the pallet fork facing the other direction.

Got it finally.  Not sure I know how for next time. Thanks for the help. 

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