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omega 920 winding stem


gary17

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Time for me to go hide myself.especially if gary is a boxer.  

The hole in sliding pinion is couple of mm deep, too much material there to be removed by alum.

I rinse, mount sliding pinion on a stem vice, spread sand paper on flat glass, drag the winding pinion side on sand paper( stem vice prependicular to flat surface) to remove material from stem and part of winding pinion, this weakens its strucutre, remove by braking the crown in pieces. 

Re-soak the sliding pinion, couple of days, plenty of light taps on the stem. Easy dose it. Mr boxer.

 

Edited by Nucejoe
Remove winding crown by breaking in pieces
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4 hours ago, gary17 said:

Hey

Is the crown wheell also called the winding pinion?

gary

No, crown wheel sits on barrel  bridge and mesh with ratchet gears.

Eternaltools.com names parts on an illustrated glossary of parts according to ETA.

Best 

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10 hours ago, Nucejoe said:

No, crown wheel sits on barrel  bridge and mesh with ratchet gears.

Eternaltools.com names parts on an illustrated glossary of parts according to ETA.

Best 

Oops my mistake.  Ignor my previouz post.

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This is a very solid movement, so 99.999% sure nothing shifted. If all's free up to the escape wheel good chance theres a hair or whatever under the cock causing it to tilt and clamp down. Or maybe an escape wheel pivot is bent/rusted/damaged.

 

 

 

 

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Hi Gary  If doing all that has been advised the escape wheel is still tight remove all other wheels and fit the escape wheel on its own after checking that the pivots are dot damaged or bent that way there is no interaction with any other part only with the part you have issue with and it should be easier to track the fault. One thing check the seating where the escape wheel bridge sits for dings or delves, these were some times used to alter the height of plates ad bridges.

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Yer

The escapement wheel is not damaged. The escapement pivot will not fit into jewel in escapement Bridge. It's fine until you tighten then the hole in the jewel holds the pivot to tight. 

Try and work out what my next step is. 

Cheers gary

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If fork pivot dosn,t get into its jewel,  perhaps wrong fork or wrong jewel.

If it dose get in, but fork gets stuck as you tighten bridge screw, you need to adjust fork jewels.

Jewel adjustment should bring pallets to level with escape wheel for proper pallet- teeth interface. 

Gentle champ :judge:.  

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Pallets and escape teeth should level, geometricaly in one plane.

If the lower fork pivot gets in lower jewel hole ( hole on the mainplate), chances are the jewel in fork bridge is a wrong one.

Fork bridge may have been shimed which got washed away and you didn,t notice, wrong arbor fitted on right fork, wrong arbor& fork, wrong jewel.

 

 

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Yer 

i have stripped the plate and started again with just the escapement wheel and bridge.

That seems to work perfectly. (see pic)

I will now add the train wheels 1 by 1 and try after i add 1 to make sure its free and see were i get to.

gary

 

IMG_20191005_173610.jpg

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Yer 

Every thing works fine until i put the escapement bridge on.

But once you centre the escapement pivot to fit in the jewel hole it dont work.

So i guess i need either to make the jewel hole bigger or the pivot smaller.

gary

I have everything lined up perfectly.

If i turn the centre wheel it don,t move but if i turn the escapement wheel all the train wheels turn including the centre wheel.

This cannot be correct surely?

Edited by gary17
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1 hour ago, gary17 said:

Yer 

Every thing works fine until i put the escapement bridge on.

But once you centre the escapement pivot to fit in the jewel hole it dont work.

So i guess i need either to make the jewel hole bigger or the pivot smaller.

gary

I have everything lined up perfectly.

If i turn the centre wheel it don,t move but if i turn the escapement wheel all the train wheels turn including the centre wheel.

This cannot be correct surely?

:o:rolleyes:   

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