Vintage pocket watch - How much endshake can it stand?

[Simeon]

I have a vintage pocket watch (my father-in-law's) that I am currently servicing. It has an unsigned 'swiss made' 7 jewel movement. The movement was soaked in oil (probably WD40) but quite clean and untouched. 

Examining the movement after cleaning and before assembly, the balance is installed on the main plate and swings freely in each position but as I move it from one position to another I can hear a rubbing noise from the balance and can see vertical end shake of approximately 0.5mm as I lift the balance straight up and down. Strangely enough there is very little side shake and little wobble if I try and lift the outer edge of the balance.

My question is, how much balance end shake is too much on an old pocket watch and can it be 'simply'  corrected by pushing the jewels(s) inward with a jeweling set? (Which I don't have yet).

[Nucejoe]

Balance pivot should not jump out of the jewel hole by lifting one side of the balance rim, with moderately low force.

No part of the balance complete be allowed to rub, 

Balance should  be positioned to allow fork engage properly  with impulse jewel.

Fork pallets should be level with escape teeth. 

 Show the setting on mainplate, is it movable?  

Ideally end shake on balance staff can be .01 mm , this  reduces positional variation.

Rgds

 

 

 

 

 

 

 

 

 

Edited August 9 by Nucejoe
correction

[mbwatch]

From the side view, it looks like the hairspring stud is protruding very high through the top of the balance cock. That is not the cause of the end shake, but could easily be the cause of the rubbing sound. Try to loosen the stud screw and push down the stud to be flush with the top of the balance cock. If it stops rubbing then, that's an improvement. It's final position may be something other than flush but it definitely looks in too far right now and the hairspring isn't flat probably because of that.

[rjenkinsgb]

In the second photo, the hairspring is sitting on the end of the adjustment pins, rather than between the pins. I would think that is likely to be causing a rubbing effect?

[Simeon]

7 hours ago, mbwatch said:

From the side view, it looks like the hairspring stud is protruding very high through the top of the balance cock. That is not the cause of the end shake, but could easily be the cause of the rubbing sound. Try to loosen the stud screw and push down the stud to be flush with the top of the balance cock. If it stops rubbing then, that's an improvement. Its final position may be something other than flush but it definitely looks in too far right now and the hairspring isn't flat probably because of that.

 

6 hours ago, rjenkinsgb said:

In the second photo, the hairspring is sitting on the end of the adjustment pins, rather than between the pins. I would think that is likely to be causing a rubbing effect?

Good eyesight, both of you.

I definitely have to do some work with the hairspring. When removed from the cock it sits flat and concentric but when installed it shifts the coils and bunches it up underneath the cock.  There are a couple of problems causing this. The stud (in the picture) is definitely not at the right depth and this was distorting the hairspring. I subsequently tried lowering it which improved the shape of the hairspring but I then found it catching on the balance arm!  I think I need to tweak the hairspring where it comes off the stud and try and find a Goldilocks position with the depth of the stud.  There is also minimal/ no terminal curve where the first coil joins the rear of the spring so the regulator pins seem to be displacing the shape of the coil as well. 
The regulator pins are made up of a rotating boot and fixed pin but the boot doesn’t have a return lip that closes over the gap so the spring tends to pop out of the pins as observed   Not sure what to do about that yet. I am starting to get to the limit of what I can accomplish without having a Staking set (or jeweling set). I might need to put this on the shelf until my tooling and skills have caught up   

 

[Simeon]

23 hours ago, Nucejoe said:

Balance pivot should not jump out of the jewel hole by lifting one side of the balance rim, with moderately low force.

No part of the balance complete be allowed to rub, 

Balance should  be positioned to allow fork engage properly  with impulse jewel.

Fork pallets should be level with escape teeth. 

 Show the setting on mainplate, is it movable?  

Ideally end shake on balance staff can be .01 mm , this  reduces positional variation.

Rgds

 

 

 

 

 

 

 

 

 

I need to get a photo for you Joe but the jewel on the main plate has a brass surround and it looks like it can be adjusted in terms of depth. It has a near semispherical cap stone that is held by n place over the setting by the brass disk with the screw. The cap stone is loose and just held in place by the brass disk. 

[Neverenoughwatches]

On 8/9/2024 at 12:14 PM, Simeon said:

I have a vintage pocket watch (my father-in-law's) that I am currently servicing. It has an unsigned 'swiss made' 7 jewel movement. The movement was soaked in oil (probably WD40) but quite clean and untouched. 

Examining the movement after cleaning and before assembly, the balance is installed on the main plate and swings freely in each position but as I move it from one position to another I can hear a rubbing noise from the balance and can see vertical end shake of approximately 0.5mm as I lift the balance straight up and down. Strangely enough there is very little side shake and little wobble if I try and lift the outer edge of the balance.

My question is, how much balance end shake is too much on an old pocket watch and can it be 'simply'  corrected by pushing the jewels(s) inward with a jeweling set? (Which I don't have yet).

What you think looks enough endshake is probably way too much. Enough to permit free motion of the balance, when there is too much things can catch and rub, the escapement doesn't like a lot of endshake components will stop/restrict their interaction with each other.

[Nucejoe]

Hi Simeon

Loose cap stone  is UNACCEPTABLE.

 I don,t suppose you have a jeweling tool.

Remove the balance and cock assembly to keep em   out of harms way when you attempt moving the brass housing .

I have had success  moving the brass setting housing by pressing down  on it with a wooden stick sharpened with  pencil sharpener, to a diameter that  fits over  brass setting housing  or slightly larger diameter of the hole on mainplate.

You ought to put the balance cock assembly back on mainplate each time to check the end shake. 

A test for decent end shake is , gently pushing down on the cock whilst oscilator is oscillating, when oscilator stops your pushing on pivot ends, its  a feel one develops  with little experience. 

Adjustments need to let the escapement function unimpeded  and nothing rub.

Escape wheel and fork pallets must be level in one  plane.

Picture  and links open on my tablet. 

Rgds

 

 

 

[nevenbekriev]

Simeon, I assure You there are no brass settings there. The stones are rubbed in, they are not movable. Try to move them and they will crush. Jewel setting tool is useless here. What You describe about the semispherical cap stone that is held in place by the brass disk is because the end stone which was once rubbed in the disk has been broken and then someone made things this way to solve the problem. The axial end shake only depends on cap stones position and moving the hole stones is useless without moving the cap stones. You can't move the cap stones, the only thing You can do to reduce the end shake is to bend the balance cock a little bit down.

You need to investigate what makes the rubbing sound  and rectify it. For sure the hairspring is bent down where it comes out of the stud , so You must lift it and made it parallel to the plain of the balance, thus it will no longer tend to get out from the regulator pins. But I doubt that the hairspring has something to do with the rubbing. Look if there is enough clearance  between the balance arm and the pallet fork cock. Someone has filed the crud where it used to cover the pin, probably because the balance arm has touched it. This happens when changing the balance staff with not correct one or with no correctly turned one. One can find many problems in an old watch due to not correct servicing, but this is the way it is...

[Simeon]

5 hours ago, nevenbekriev said:

Simeon, I assure You there are no brass settings there. The stones are rubbed in, they are not movable. Try to move them and they will crush. Jewel setting tool is useless here. What You describe about the semispherical cap stone that is held in place by the brass disk is because the end stone which was once rubbed in the disk has been broken and then someone made things this way to solve the problem. The axial end shake only depends on cap stones position and moving the hole stones is useless without moving the cap stones. You can't move the cap stones, the only thing You can do to reduce the end shake is to bend the balance cock a little bit down.

You need to investigate what makes the rubbing sound  and rectify it. For sure the hairspring is bent down where it comes out of the stud , so You must lift it and made it parallel to the plain of the balance, thus it will no longer tend to get out from the regulator pins. But I doubt that the hairspring has something to do with the rubbing. Look if there is enough clearance  between the balance arm and the pallet fork cock. Someone has filed the crud where it used to cover the pin, probably because the balance arm has touched it. This happens when changing the balance staff with not correct one or with no correctly turned one. One can find many problems in an old watch due to not correct servicing, but this is the way it is...

Lots of good advice here. It would appear the watch has suffered from about a century of bad repairs so I am not likely to solve these cumulative problems with my current skill set (or tool set).

I will reassemble the watch and play with the balance / hairspring to get it flat and as well positioned as I can manage. Hopefully get it running and keeping time somewhat (say +/- 60 secs per day). I will then park it and leave it for later to troubleshoot any problems with positional running. Not much point in a pocket watch that can't run well in vertical positions. 

[Simeon]

So, got the watch running. It loses about -170 secs a day in the vertical positions, about -30 secs a day DD but it really doesn't like running dial up. It makes a bit of a rattling noise when it runs or stops all together.

I am guessing that the balance staff is sliding down in the jewels and the impulse jewel is making uncertain contact with the pallet fork.

Amplitude is about 180 degrees but this was on the old set mainspring which really needs to be replaced. The train moves nice and free, I can blow the escape wheel and it will run the train in reverse and when wound with the spring it would recoil at the end. 

After it has run for a bit, I am going to tweak the rate to try and get it reasonable in the vertical positions and call it a day. I will come back to it when I have the means to sort the balance end shake out. 

[nevenbekriev]

The big axial free play is what You need to rectify first. This may solve the rubbing problem, as rubbing is probably of balance rim on the 2nd wheel.  There are 2 ways of solving the problem with the axial free play. One is longer balance staff, and the other is bringing the cap stones closer to each other.  There are alternative solutions used by old watchmakers, like putting small pieces of mainspring between the capstone and hole stone, but I don't find it acceptable. What You really can do (and the only thing too) is to bend the cock down. Just a little, only to make the end shake more acceptable.  It is easy to do - put the cock in place without balance, tighten the screw and press to achieve just little deformation, then try the result.

Then, do the free oscillations test. Do it in both DU and DD positions and see if there is difference. Do the test with only the balance in place, no train and spring bridges. If rubbing still exists, then it's source must be searched.