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Poising/timing balance wheel


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Ok folks, quick question (once again), balance wheel timing screws, looking at the photo of the bare balance wheel you will notice no timing washers but two meantime screws are adjusted outwards. This wheel is the original wheel from the movement.

Due to a HS malfunction, old rusty and snapped during manipulation, a few eBay purchases to find a suitable donor and one came along, ( see picture of balance on cock in movement ) you can see that next to the meantime screws there are timing washers fitted to the screws opposite each other as it should be. 
Now the movement ( English lever going barrel ) was running nearly 7 hours fast in a 24 hour period!!!!!!!
This is after I had made a new pallet arbor which was magnetised as were most things on the movement. I have stripped and demagnetised the whole movement in individual pieces. 
It has slowed, now only gains approx 2 hours in 24 hours even with the regulator all the way over to slow. 
I have tried to transfer the HS to the original balance wheel but the collet size is  different and I don’t want to start messing with opening/closing the collet just yet to make it fit ( maybe I might have to ). I’ve never pinned a HS to a collet let alone removed one from a collet to re fit it to another collet so no experience in that department. 
Would it be an option to turn the meantime screws out, working in opposites and equal turns to each screw that is moved?
This is a project watch albeit a long term one so some tinkering in that department is an option, although a lot can be learned from books etc it’s nice to have someone with far greater knowledge and experience point you in the correct direction.
In your opinions, what options do I have to slow this movement down? I know adding weight to the balance would do this according to frieds book, I would of thought that removing weight would of slowed the action but maybe that’s just me having a brain fart as trust me I’m no expert here just a tinkerer. 
Thanks for any answers that may help/ enlighten me to solving this conundrum.

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Edited by transporter
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Turning screws outward slows the oscillator, but you should check the wheel for poise. You are assuming you have a poised wheel to begin with and furthure that with equal turns the poise is kept unaltered.

To slow down an oscilator, adding weight is not a neccessity, in fact is a minus since you are increasing the weight on pivots.

As you turn the screws outward, you are moving the meanweight of the wheel outwards, which increases the tendency of the wheel to resist change in its motion( inertia), while the mass dose indeed remain the same.

In watchrepair inertia is refered to as weight, just to make it simple for folks to invisige the concept.

As you move the meanweight outwards the wheel puts up more resistance to any change in its motion ie; accelerate or decelerate, which the oscilator dose go through in each beat. The increased resistance slows down the velocity of the wheel, think of velocity as speed for now.

The problem you will have is if the screws are not tight( on washers you were suppose to have added) screws may turn loose, unlessthey  feel tight enough not to loosen during years of oscillating to come.

In short you are regulating as you poise or keep the poise the wheel had. The two go together for a healthy balance and to avoid excess positional variation.

Hope this helps. Good luck.

 

 

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Ahhh now you see we now have to differing answers, or three if we include Frieds book, 

He states that is a watch was running slow, it would be safe to remove weight from the heavy screw/remove washer. Which goes against what Nucejoe said. 
Fried then says I’d watch ran fast, a weight ( washer) might be added. ( or screw out the screws) Which is in agreement With Rodabod and what I thought at first. 
So now a tad confused as to wether add or remove, both answers make sense to me but have totally messed with my mind as what my knowledge of weight, enertia and rotation was haha

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Hmm I think all three Fried, Nucejoe and rodabod says the same thing but in different ways, moving or unscrewing the meantime screws outwards will slow the balances oscillation down, Fried just do it the right way by adding a washer"weight" will assure the screw stays in place, just threads will not assure this. By adding the washer it will move the meantime screws position outwards and add a slight weight and by that slow the balance oscillation down. Taking meantime screws off or tighten them  will make the balance increase the oscillation and the watch goes faster.
 

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11 hours ago, transporter said:

running nearly 7 hours fast in a 24 hour period

 

11 hours ago, transporter said:

gains approx 2 hours in 24 hours even with the regulator all the way over to slow. 

your title makes a reference to poising right now you're having a timing crisis are you also suggesting that your balance wheel is not poised?

first off let's look at the normal things that make a watch run fast just to eliminate the problem ignoring at least I'm going to ignore that you have the wrong hairspring. So make sure that the wrong hairspring is only touching at the collet the stud and the regulator pins. Make sure it's flat is not touching the balance arms for instance. As it has a over coil make sure it's not touching the top of the balance bridge. A lot of people don't pay attention to the over coil and it can rub on the bridge. So providing the hairspring actually fits within the space you're really screwed for running fast.

so timing washers typically are applied in pairs that's to keep the balance wheel poised. The assortments are typically in minutes per day and the typical numbers you would have would be one, two and three you might be lucky and have a set that has four minutes per day. Last week when I was adding a mantra balance wheel that I poised after restaffing that set only had three. So I needed to pairs of washers and the regulator to get it back in time. You're going to require a tiny bit more like two hours is equal 220 minutes divided by the three minute washers that equals 40 pairs that you need to add. That is considered an extremely unacceptable number seeing as how you only have six pairs of screws that you can add them. Now you do not put them under the mean time screws and the mean time screws will not adjust this grade of time so just leave them alone. So with six pairs of screws each screw would have to have a unequal number you need about 6 to 7 under each screw that is considered unacceptable.

I don't suppose the balance wheel has any extra holes? Because the only way you're going slow this down more in anything resembling something acceptable would be to add new screws they'll get you around 15 minutes and that would be per screw. Because typically if a screw falls out your watches running 15 minutes fast it stands to reason adding a pair will slow you down about 30 minutes that made to date about you than do the math. Or to take the screws off you have now and see if he can find something bigger and heavier or perhaps made out of gold that would be even better.

as this is a vintage watch really vintage I don't suppose the hairspring pinned at the stud as any extra length sticking out? A lot of times on vintage watches things weren't as exacting as they are now and there would be a little extra space? Sega just unpin and lengthen your hairspring that would help considerably.

Did I mention up above that you have the wrong hairspring? So unacceptable fixes would be you need a balance wheel that has greater in this gets confusing? Notice how with the mean time screws all you're doing is moving the mass farther out not changing the way to the balance wheel? Adding a timing washer increases the weight. If all of the fixed screws were moved out by a Maybe one full turn that would be like they would all become mean time screws but you would have to Loctite them in place because otherwise are going to fall out and what I'm suggesting is not considered appropriate.

I think it probably be better if you could find a hairspring that was closer to what it's supposed to be. Because two hours fast is considered extremely fast

 

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Very comprehensive answer there mate, thank you for all the information, I will pop off the bench and study and see what the problem can be, the hairspring is the correct spring for the wheel, I haven’t changed that, I have replaced the balance wheel and hairspring complete onto the old balance cock.

There is no spare HS at the stud, the overcoil is free to move between the cock and wheel, the Hs vibrates nicely between the regulator pins. The train is free, each wheel tested individually then with the the next in line and so on and so on until the whole train was tested for free running, the pallet ( lever ) flicks over with the lightest of touches when there is power on the train. 

Head scratching time no I think 

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Ok so I’ve just done an hours test next to a trusty quartz and in that hour it’s gained 10 mins???? That’s on a full wind, the regulator is set in the middle, I shall now leave it to see what happens over the next few hours and report back with my findings. 

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32 minutes ago, transporter said:

balance wheel and hairspring complete onto the old balance cock.

it's probably due to the early of the morning at least here so you replaced the balance completes on a English lever watch?

I assume you verify that the roller jewel the size the roller table etc. all of that was exactly the same as the original one?

then there might be another problem? My brain doesn't really want to think about this but usually English lever watches are relatively old and they may not be running at 18,000 beats per hour. I suppose it's possible that you got a balance wheel running at a different frequency?

 

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 I'd move the regulator all the way to slow then time the watch on bench, if still running  fast, you then look into slowing down by moving the screws out, you may not need to move screws at all and regulate by the regulator.

Even if not poised, watch can keep good time in static positions with FU or FD, but fail good timing in other positions.

So lets first find out if your balance complete, that is the wheel as is and the hairspring would vibrate to the beat( to generate the design beat ). if it dose there is no need to move screws, you can simply regulate it by the regulator. 

If the balance complete did not produce the design beat, you would then alter the wheels inertia by moving screws to produce the design beat and then poise.

I hope this is not confusing.

 

 

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