Cylinder escapement beat setting....help!

[Alun]

Hi all....

I posted this nice ladies fob watch in another part of the forum to see if anyone could ID it.... however....noting it needed some love I had to change the balance wheel as the cylinder was broken.

Remarkably I had a spare and it fits really well with a slight end shake, but....

I read up on how to set the beat and I lined up the 'banking pin' on the balance wheel with the escape wheel pivot hole, so there's a straight 'line' between the escape pivot, pin and balance pivot.

So is this right? How can I test I've done it correctly?

The watch doesn't run and I want to make sure this is correct first before I go into it deeper..

 

Cheers Al

[watchweasol]

We are supposing the train is free running ok. The method you describe is correct.  Is the balance free in motion, power down the movement remove escape wheel and balance, re fit the balance wheel on its own then using a blower/puffer give the balance pa puff. Does it oscillate for up to 20 to 30  seconds on its own . When it stops how does it line up . The method you described as far as I know applies to lever watches with a pallet /fork. The cylinder is a whole new ball game as there is no fork.  Look at the position of the cylinder in respect to the escape wheel teeth.

[Alun]

Hi thanks for your reply and the simple answer is yes....

The balance swings great without the escape wheel in place.

There's power all the way through the train.

If the balance is in beat my inclination is towards the escape wheel not being compatible with the spare cylinder I found in my stash....like either the cylinder is too high/low..wrt the escape wheel, so what does good look like?

Or the diameter of the EW is too big and fouls the inside of the cylinder....and yes this cylinder escapement is a whole new ball game to me

[watchweasol]

I would fall on the side of the new cylinder is not compatible for what ever reason. It obviously worked with the original balance. The cut portion of the cylinder is probably cut different.  A lot of these were cut to fit, so obtaining a new clylinder will be difficult. Collections of cylinders come up on the bay at times but you still have to find one the same as the original.  Many moons ago I had one cut and fitted but there days it’s a service that if you could find someone to cut one and fit it the cost would be prohibitive.

[Alun]

Yes I have to agree I'm clutching at straws but at least I've learnt about cylinder escapements

[watchweasol]

I think the reasonable path to take is case it up and place in the jobs in progress drawer to be kept an eye on should the right time and part arise, which it may do and move on to another project.  Good luck

[nevenbekriev]

Hi Alun,

You have replaced the entire balance? If so, then the fact that it rotates free in the bearings means nothing.

There are certain rules that will ensure a cylinder to fit in a movement.

1. The diameter of the cylinder must be the same as the original. If You replace the cylinder, but the balance wheel is original, then it is enough that cylinder fits tight in the hole of the balance wheel. If original parts are missing, then the cylinder must get free between EW teeth AND the teeth must enter free inside the cylinder

2. The position of the mouth of the cylinder in height must comply with EW teeth  position in height. The cylinder mouth has 'two floors' and again, the EW teeth have 'two floors' -the teeth themselves and the base of the wheel The teeth must be corresponding to the 'second floor of the mouth (which is cut 180 degr) and the base - to first floor (which is cut 270 degr)

The cylinder is correctly oriented and 'in beat' when the hairspring positions it as the mouth 2nd floor is pointed directly to the EW bearing. In the same time, the limiting pin on the balance rim must be 180 degr. from the limiting pin on the balance cock.

The escapement depthing must be checked when cylinder is replaced and corrected if needed - the depth must be as small as possible when reliable drop lock still exists. Depthing is changed by moving the entire balance cocks couple.

Edited February 17 by nevenbekriev

[Alun]

On 2/17/2025 at 2:22 PM, nevenbekriev said:

Hi Alun,

You have replaced the entire balance? If so, then the fact that it rotates free in the bearings means nothing.

There are certain rules that will ensure a cylinder to fit in a movement.

1. The diameter of the cylinder must be the same as the original. If You replace the cylinder, but the balance wheel is original, then it is enough that cylinder fits tight in the hole of the balance wheel. If original parts are missing, then the cylinder must get free between EW teeth AND the teeth must enter free inside the cylinder

2. The position of the mouth of the cylinder in height must comply with EW teeth  position in height. The cylinder mouth has 'two floors' and again, the EW teeth have 'two floors' -the teeth themselves and the base of the wheel The teeth must be corresponding to the 'second floor of the mouth (which is cut 180 degr) and the base - to first floor (which is cut 270 degr)

The cylinder is correctly oriented and 'in beat' when the hairspring positions it as the mouth 2nd floor is pointed directly to the EW bearing. In the same time, the limiting pin on the balance rim must be 180 degr. from the limiting pin on the balance cock.

The escapement depthing must be checked when cylinder is replaced and corrected if needed - the depth must be as small as possible when reliable drop lock still exists. Depthing is changed by moving the entire balance cocks couple.

Hi there... sorry I didn't get a notification that you replied to my post! 

 

Thanks for the advice really helpful and I did get the watch going using an EW from my stash of scrap movements... But....and a big but....the EW had too much end shake and as you said the EW teeth just didn't like it when I inverted the watch.

It was a good little 'learning piece' and I appreciate your help.

Cheers Al

On 2/16/2025 at 9:25 PM, watchweasol said:

I think the reasonable path to take is case it up and place in the jobs in progress drawer to be kept an eye on should the right time and part arise, which it may do and move on to another project.  Good luck

Yep....and in the drawer of doom it went