Jump to content

setting for beat error for cylinder escapement


Recommended Posts

I am currently working on an old small pocket watch which has a cylinder escapement.  The hairspring on the balance is a little out of shape towards the regulator end. If I have to remove the hairspring from the balance staff to resolve shape then how do I reset it back on the balance staff so that it will be in beat, or near enough as a starting point before adjustment of the hairspring collet position on the balance staff.  I know with a swiss-lever that the table jewel can be visually be aligned with the pins and the lever pivot and escape wheel pivots, so is there a similar method for a cylinder escapement bearing in mind there is no lever.  Any advice much appreciated.

Link to comment
Share on other sites

  • 2 weeks later...

Thanks, that's very useful.  I have had to put this project to one side for now, hence my delay in responding.  I have had a quick look at the balance wheel and it does have 3 drill spots on the dial side of the wheel rim and a strange projection (like a pivot) sticking out of the rim of the wheel,  I cannot see any dots on the plate at first sight.  I'll try a get some pics and post again later when I resume this project.

Link to comment
Share on other sites



  • Similar Content

  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • That's a good idea - shrinking down the nut and wrench size from the old casebook trick!
    • I missed this earlier. The dial isn't going into the holder, it should sit proud of it. This is what I am currently using which I print for each different movement.    
    • I didn't think pulling to set position would work harden the spring, in that position it is stressed where the arm starts. By work hardening i meant rapid polishing at that point, a bit like polishing a pivot work hardens as it compresses the steel. I doubt polishing by hand would achieve much in that respect though. Its finished, arm polished up mostly at the join to the bridge's main body. I'm ok with it, the screw holes aren't great as i had to open them up by redrilling and positioning it was difficult, I'm not much use with a loupe, opening up with a file might be a better option for me or i could just use the correct drill size 😅. And the detent is way too deep, i had to guess that with the stem release out of position and sat on top, but i only took one measure and went for it, no slowly slowly catch your monkey 😅. First go I'm happy , well sort of, it works and thats a big thing for me, next one will have a bit more finesse.  Anyone thats interested, after filing, i used a 2000 grade home made diamond  micro file and then 20 micron film, the film is much better than wet and dry, more stable to use and doesn't shed cheap grade grit everywhere , then auto polish on a sponge pad.
    • I'm assuming that every time you set the watch you are work hardening the detent spring, maximum hardening is  where it meets the plate due to maximum deflection.   That's why it snaps there.  The Young's modulus may be the same but after it's reached its maximum yeid strength it breaks.  My mechanic engineering is very rusty, correct me if I'm wrong. 
    • Ah ok yes that makes sense to polish it where the arm starts to form from the body of the bridge, i thought you meant the underneath of all the arm.
×
×
  • Create New...