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Poor Amplitude

TheoB

By TheoB
in Watch Repairs Help & Advice

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TheoB Member

TheoB

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6 hours ago, nickelsilver said:

I'll look in the books when I'm in the shop tomorrow, I'm sure we'll find the maker. Can you measure the outside diameter of the movement? 12s is American but that's a Swiss movement.

the diameter of the main movement is 41.76mm and the little lip on the dial side has a diameter of 42.76mm

22 hours ago, saswatch88 said:

You need to check balance staff pivot under a microscope, the tip could have gone flat, they should be concave since this is a Swiss movement. If they are flat it will cause too much friction and will result in low amplitude and the watch will run very fast.

ive attached a couple photos of the top and bottom pivot, they done seem to be bent or anything but I'm not sure if you would call them 'concave'.

tearing the movement down again a found a slight chip in the third wheel jewel, would this account for the amplitude problems? I would have expected it to be a problem with the faster end of the power train. 

IMG_0769.jpeg

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saswatch88 WRT Addict

saswatch88

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Posted
3 hours ago, vinn3 said:

    please explain " re cased pocket watch".   during the era when those  were   popular.case and the mvt. could be sold separitely by the jeweler .   my granfathers elgin RR case could be sold with 2 diferent number of jewels.   a jeweler would replace your gold case with silver or nickel  -  if times were  tough.    vin

 

 

When i say re-cased i mean people who take the movements then case them in an aftermarket wrist watch case.

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jdrichard Distinguished Member

jdrichard

Posted
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ive attached a couple photos of the top and bottom pivot, they done seem to be bent or anything but I'm not sure if you would call them 'concave'.
tearing the movement down again a found a slight chip in the third wheel jewel, would this account for the amplitude problems? I would have expected it to be a problem with the faster end of the power train. 
IMG_0769.thumb.jpeg.62f7a68f24c60d80b65e86a41747ad30.jpeg
IMG_0770.thumb.jpeg.a68c91d532badd8bccee8b3edd201b8a.jpeg
IMG_0767.thumb.jpeg.3f5e61804d85b96d55a8fa1f57c1b019.jpeg
IMG_0768.thumb.jpeg.ffe56624e7d91a98644979bca3a86fde.jpeg

The jewel hole seems to be cracked....this is your problem

Sent from my GT-N5110 using Tapatalk

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transporter Super WRT Addict

transporter

Posted
Posted

along with the damaged jewel, have you been oiling the pallet? it has been said on here before i believe that some of us dont oil the pallet fork jewels due to the lightness of said component etc, anyway it has been proved that not oiling the pallet fork jewels can increase the amplitude without any detrimental effect on the train

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TheoB Member

TheoB

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1 hour ago, praezis said:

Hi Theo,
your movement is a Damas 9 (height 5.2 mm).
Mainspring 1.9 x 16 x 0.20

The jewel has more than a 'slight' chip and should be changed. Also the pivot shows considerable wear!

Frank 

Thanks for looking that up Frank! 

I guess this is another one that will get put in the drawer until I get set up for jeweling. 

Thanks for all the help everyone. 

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