Beat adjustment

[dnhb]

I'd be grateful for recommendations of good sources of advice on getting clocks with balance spring - as opposed to pendulum - escapements 'in beat'.....

[oldhippy]

I don't know if there is a timing machine for balance spring clocks. If not it is a case of trial and error. You should make a note of the position of the regulate and work from there.   

[transporter]

Has it got a beat adjustment on the platform or is it a fixed hairspring? in short what you are looking at to get it just about in beat is to get the roller jewel sitting dead centre between the banking pins.

So remove the platform and take of the pallet fork and escape wheel to give you clear line of site, sit the platform with the balance in place and with it level look between the banking pins and see if the roller jewel is sitting between them, if it is nice and central its there or there abouts in beat, if its not the the position of the pinned end of the hairspring needs to be adjusted to move the roller jewel into the correct position, thats why I asked if it has an adjustment on the platform or not, if it has its an easier job. 

[MikeEll]

Yep, basically the same principle as for watches with a Swiss lever escapement.  The position of the hairspring collet needs to be adjusted/rotated on the balance staff such that the impulse jewel sits perfectly at rest between the banking pins when there’s no power to the pallet fork.  On some escapements, there’s an actual beat adjuster, but I’ve never seen one on a clock.

Edited June 3, 2024 by MikeEll

[dnhb]

Thanks T & A. No banking pins on this one but I applied the underlying principle you expounded in ensuring by adjusting the collet so that the pallet fork swung equally either side of what I judged to be the centre line & this worked !

[nevenbekriev]

The impulse pin mus be exactly on the line balance bearings - lever bearings

[dnhb]

1 hour ago, nevenbekriev said:

The impulse pin mus be exactly on the line balance bearings - lever bearings

Yes. Nev, my p.o.v. was such that the 2 arbors were in line. Thanks.