Bent Escape Wheel Pinion, Pushed Jewel to Low?

[Tracy]

I successfully managed to snap off the pinion on the escape wheel of the Favre Leuba Cal 253 movement I’m working on. I thought the pinion was in the jewel hole on the wheel bridge but it wasn’t and when I screwed down the bridge and bent/snapped the pinion off.

Before I tightened the bridge mounting screws I looked to see if the pinions from the 3 wheels were visible in the jewel holes (used a 45x loop). I guess I didn’t see the escape wheel pinion—maybe the light reflected and it looked as if it were in the jewel hole. 

My questions is in pushing the escape wheel down when I broke the pinion could I have moved the plate jewel lower into the plate?

The reason I ask is that when I take the wheel bridge off the lower gear on the escape wheel is too low to engage the center wheel. Without these two gears meshing there is no power transmitted from the main springs to the escape wheel.

I made a “not-to-scale” drawing to illustrate the problem. Could the plate jewel be too far into it’s hole thus lowering the height of the escape wheel?

 

[rogart63]

Could very well be so. Even think i have done it once. Ususally the jewel are flush to the mainplate. 

Edited June 10, 2017 by rogart63

[clockboy]

It's so easy to do this. In my early days of watch repair I did it a few times.

The key to it is when tightening down the bridge/plate only put the tiniest amount of pressure on the screws and test for freedom of movement of the wheels as to go.  If it is not aligned then the wheel or wheels will stop spinning freely. But because you have only put the tiniest amount of pressure on the pivot/s they will still be OK. 

[Watchtime]

A wellknown problem, I have experienced this myself a few times....as CB says, just a tiny bit of turning the screws and then test if the wheels are spinning.

[Tracy]

Thanks to all who replied. I have a spare movement on the way (from ebay/India $17 with free shipping), U will use the escape wheel from it. I will try to push the jewel back into position but if that doesn't work I'll use the base plate from the spare watch. 

[anilv]

Hi Tracy,

Most of the jewels are pretty snug in their holes so it is unlikely (but still possible tho'!).

1. One thing I remember is that these movements (love them btw) have double barrels. I would check if swapping the barrels helps. I seem to remember they were slightly different I think you would need to swap the mainspring arbours as well.

2. Also, was the watch working before you dismantled it?

3. If the jewel has sunk into the hole, the upper pinion (in your pic) would also not mesh with the seconds wheel. not easy to check now with the broken pivot but you should be able to hold the wheel upright with a bit of Rodico.

4. Do you have a spare wheel?

Anilv 

 

[anilv]

to add..

Looking top-down on the jewels to see if the pivots are in place doesn't really work.You need to eyeball it from the edge, the wheels should be level (the escape wheel is usually the last to get in place) and there should be no gaps between the bridge and mainplate. Even when you're sure the pinions are in place, give the mainspring a push by using a tool on the barrel-edge  where it shows on the side of the movement.. everything should spin freely. Turn the bridge screws a few turns each and push the barrel edge again... You will reach a point when the bridge is fully home and wheels are turning well, this is when you finally use a bit more force to fully tighten the bridge.

If you're assembling the movement with the train wheels first followed by the barrel/barrel-bridge. You can use the same technique but push the arms of the centre wheel instead.

HTH

Anilv

[Tracy]

Anilv,

Yes I bought a spare movement and I will use the escape wheel from it to replace the one I screwed up. If I can't push the jewel back into place I will also use the spare movement's base plate.

To answer you other question, yes the watch worked before I took it apart--with a full wind if ran for about 38 hours.

When I used to be on motorcycle forums I was the guy that provided advice/answers to questions and I was always happy to help the FNGs. On this and other watch forums I'm the FNG and I do appreciate everyone's kindness. Thanks again to everyone who replied/helped me out.

[StuartBaker104]

This is a lesson that most of us learn the hard way, but hopefuly not too many times!

A lot of the movements I have seen from India have hade some creative repairs.  Cousins has the escape wheel in stock for £10 if your scrap movement doesn't have a good escape wheel. https://www.cousinsuk.com/category/favre-leuba-movement-parts

As Roger says, usually you will find the escape wheel jewel flush with the inside face of the main plate. Even without a jewelling press you may be able to push it back against a flat plate. Ideally you would use a hollow punch, but a flat one should be ok. Finger pressure is likely to be enough. The end shake (axial play) on the escape wheel should be about 1/100mm, although that is easier to write than to measure!

[Tracy]

I've now ordered tow watches from this guy in India and all have worked. Hopefully the one on its way will be the same and I'll harvest the escape wheel from it. Thanks for the link to Cousins--with the cost of the escape wheel and shipping the one from India is less expensive ($17 including shipping) Now I have an entire movement for spare parts. I'm happy with two working movements/watches and one for a spare.

[jdm]

Moved to repairs help & advice.