Causes of positional rate changes

[Bonzer]

I have a movement (Seiko 6119C) on which I have had to make some adjustments to the balance spring because it was slightly mis-shaped.

I have had it running with a consistent rate in all positions but after a self-inflicted injury to the hairspring again, I have had to make more adjustments but since then I get some major sudden rate changes as soon as the movement is moved to a new position. 

What I would like to know (for this movement and others in the future) is what aspects of the spring/ balance assembly can cause such positional rate changes, aside from an out-of-poise balance wheel?

[JohnR725]

13 hours ago, Bonzer said:

I have had it running with a consistent rate in all positions but after a self-inflicted injury to the hairspring again, I have had to make more adjustments but since then I get some major sudden rate changes as soon as the movement is moved to a new position.

Looking at the part that I've quoted you indicate that everything was fine. Then hairspring problem now you have problems? I would say it narrows down the possibilities to something you did here?

13 hours ago, Bonzer said:

What I would like to know (for this movement and others in the future) is what aspects of the spring/ balance assembly can cause such positional rate changes, aside from an out-of-poise balance wheel?

Is a minor conflict here in that you indicated hairspring incident and now you're asking for all other things?

It would be really helpful to have better definition of what you're seeing and of course in my case I love to see pictures from your timing machine. Especially if you could show on the graphical display capture an image right when this change occurs these are not 100% sure what you're saying

Then because this is a Seiko I have to make a bunch of guesses. The reference to Seiko is usually Seiko watches run at lower amplitudes. Lower amplitudes become a problem in that basically everything gets magnified. Positional errors become very interesting as amplitude picks up.

Then in addition to static poise in other words the balance wheel is physically out of poise that will cause a positional problem that won't change that will stay that way until you physically change that.

But there's also something called dynamic poising this is where you poise the watch with the balance wheel running. That takes into account everything the balance wheel the hairspring. If you as you back she demonstrated make some interesting changes the hairspring like your grossly off-center that will cause issues. Or if in the midst of this you manage to open up your regulator pins that can cause some interesting issues in that as the amplitude drops of the regulator pins are far apart the watch will slow down. There is currently a discussion now that's talking about chronometer grade watches and positional problems.

But one of the things you didn't tell us is how much of a problem are you seeing?

So went back and reread everything be really nice to have timing machine pictures. I think that would be really helpful for all of us.

Oh the attached image it does kinda show one of the minor problems of Seiko watch in that as they tend to run it at much lower amplitude. I seen a reference in one other documents for that she tell you what a good amplitude is and it is below 200° you can see were problems rapidly get magnified. So somehow in the managing of fixing the hairspring you cause an amplitude decrease as the chart shows that would also cause things look much worse.

[Bonzer]

On 6/15/2022 at 12:34 PM, JohnR725 said:

Looking at the part that I've quoted you indicate that everything was fine. Then hairspring problem now you have problems? I would say it narrows down the possibilities to something you did here?

Yes, that was my conclusion too

On 6/15/2022 at 12:34 PM, JohnR725 said:

Is a minor conflict here in that you indicated hairspring incident and now you're asking for all other things?

Because it seems this is something I have caused whilst adjusting the hairspring, I am asking for information on all the potential causes related to the hairspring, balance cock, and balance wheel. In this way, I can check for each possibility.

Interesting comments about the amplitude compounding positional errors because in the this case the amplitude is about 200, sometimes below that.

I did check the hairspring for being centered and it does look central. There is a small gap between the regulator pins and the spring bounces between those in all positions.