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Re-assembly. Aligning pinions and jewels.


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It's about as difficult as I anticipated. An hour's randomised fiddling enabled me to refit the pallet/bridge But I'm having even more difficulty with the next longer pinion. How on earth you fit a bridge with more than one pinion I can't even imagine. I'm working on an AS "Trench Watch" with separate bridges - which I also anticipated would minimise this problem. But it still seems extraordinarily difficult, particularly with monocular vision. I only have stereo capability at about x3.5.

I guess the answer is "practice for about 10 years" however as that's probably about my total remaining life expectancy - if I'm lucky - so I'd like to accelerate the process a bit. I'd appreciate any tricks of the trade that might be offered - and apologise for the cascade of beginner's questions.

Roy

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I occasionally use dentists tools to maneuver the wheels into place. Mostly though, it's practice, and learning how to see through a loupe. 

Early on I put a 7S26C train bridge on and off over a dozen times just to get a feel for it.

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Just finished assembling my test having cleaned it all yesterday. Many of the jewels were in bad shape and I suspect I haven't exactly improved them. It doesn't run of course... 

Still, I thought that the balance would be the biggest problem as the sight of a hairspring gives me a nasty feeling, but that's fine. It's just the entire train that seems locked solid. Many hours spent and I hope not wasted. It'll be a while before I attempt to clean something of value. I have at least a hundred of these in variously bad condition so it'll be a while before I run out of cadavers to dissect.

Roy

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I had to chuckle at this. Balances / hairsprings still make me twitch too as if anything's going to go wrong it's usually around this area!

I've also recently cleaned and, to my delight, got working an old AS multi-bridge movement as per the attached. Like you I thought that multiple bridges would make things easier but, and it's usually the escape wheel that is the trouble maker, it still took longer than I thought to reassemble!

I certainly always have the balance and pallet fork removed so it's easy to check for free spinning of the various wheels. I use a x5 (and sometimes x10) loupe and it's getting the movement at such an angle where you can easily see each pinion is vertical; not always easy on some movements! Even if I'm sure on this I only ever screw down the bridge(s) by teeny tiny increments checking for free movement of wheels all the way. Sometimes it's easy to see if a pinion is in a jewel (bright light; high mag); other times it's just a case of patience and gentle nudging. Always a nice feeling when those wheels whirr around smoothly!

AS_SeparateBridges.JPG

Edited by WatchMaker
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Hi Skridlov,

pallet usually gets installed after the other train wheels but before the balance wheels.

When you say the balance is 'locked up', the first thing that comes to my mind is that the impulse pin is not in the pallet fork. Does the balance move one way but comes to a sudden stop the other way?

Anilv

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Thanks to both of the above contributors. To clarify, the balance is actually free and with a couple of puffs of air oscillates in a very healthy looking manner but the escape wheel is reluctant to budge despite the pallet looking OK too. I think that the problem is in the train where numerous jewels are at the very least cracked and after US cleaning have started to disintegrate. I reassembled the movement despite this just in order to get a feel for the process. Overall I'm moderately happy for a first attempt - to date I've only successfully replaced mainsprings and sorted out a number of keyless work problems.

With the low value items I have - which describes most of them - the problem is usually a sticky hairspring; de-magnetising the whole movement and cleaning the spring with lighter fuel will often revive them. I'm seeing numerous movements which are otherwise pretty clean racing beyond correction by the regulator on account of this hairspring problem. Or that's what I assume.

I'll have another go at a similar movement. I probably have over 100 "trench" watches with some duplication of movements so I may be able to cobble up a few FrankenTrenchWatches. Better than scrapping them.

I bought some Elma(?) cleaning fluid from Cousins and also some Isopropyl. Overall, despite a non-working movement, I'm reasonably happy with the first attempt. But expect some further irritating questions...

Thanks again for the valuable tips, much appreciated. I wish I could reciprocate.

Roy

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Haven't any tricks but I've found that you need to have your head over the movement as close as possible but still able to manipulate the wheels in place. I find 8x magnification perfect for me.
If your moving your head or the movement to see if the wheel is in position, you're not over the movement enough.
Whether you place the screws in the bridge prior to final tightening, is a matter of preference. Whats very important is the bridge is held in place with gentle pressure while the wheels are manipulated into place and that pressure is maintained at all times during the tightening of the screws.
Constantly check the free running of all the train wheels during the securing of the bridge.
It's normally the escape wheel that tends to wobble out of place.
With adequate lighting, correct magnification, head position, you can see the position of the pivot in relation to jewel hole as you manipulate into position. Not so easy with a "bushed" movement.
Never attempt to assemble a movement if you have pressing business elsewhere or you have a self imposed time limit on the work. It's all about patience and being relaxed


Sent from my SM-T585 using Tapatalk

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its art work lining up the pivots,  especially into capped jewels.  its much easier without the balance, but,  setting the balance is an art of its own.  vin

Hi vinn3,

I find capped jewels easier as the jewel is usually dished on the inner side, allowing the pivot to be guided into its hole.

Of course, the cap jewels need to be installed first.

Anilv

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It's comforting (well, almost) to see that this is inherently difficult and not that I'm struggling with something others find relatively straightforward. It doesn't stop me imagining some kind of micro-jig though...

I've generally found that with processes like this - in software as well as hardware - there usually comes a breakthrough where the subconscious "knows" how to do tricky stuff. At my age though, that doesn't come as quickly as it once did. Luckily I've got a lot of similar dead movements to practice on. I'd thought of starting on pocket watches, of which I also have lots of movements, on account of their larger size but something tells me that's just avoiding some of the problems and familiarising me with movements that are too dissimilar.

And yes, there are definitely times when I need to walk away and do something else.

Roy

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It's comforting (well, almost) to see that this is inherently difficult and not that I'm struggling with something others find relatively straightforward. It doesn't stop me imagining some kind of micro-jig though...
I've generally found that with processes like this - in software as well as hardware - there usually comes a breakthrough where the subconscious "knows" how to do tricky stuff. At my age though, that doesn't come as quickly as it once did. Luckily I've got a lot of similar dead movements to practice on. I'd thought of starting on pocket watches, of which I also have lots of movements, on account of their larger size but something tells me that's just avoiding some of the problems and familiarising me with movements that are too dissimilar.
And yes, there are definitely times when I need to walk away and do something else.
Roy

Definitely a good idea to walk away if things are not going well and come back to it another time.
I've struggled ridiculously to seat the wheels in the train bridge before, only to come back to the job another day and all done within 10 minutes.
There's no micro jig[emoji16] I suppose looking at modern manufacture, most production can be done by machine but to the hobbyist or repair/ small manufacturer, it's all about craftsmanship.
Really to achieve great proficiency, you require formal training lasting several years under a "Master"
Enjoy as a hobby and remember, all the disasters make the successes even sweeter

Sent from my SM-T585 using Tapatalk

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