Decent accuracy, but poor Beat Error

[snowman]

Hi all.

Be gentle with me as I'm very new to this!

I've a microbrand watch with a Selita SW200 movement.

It was losing 3 minutes a day and no amount of regulating would resolve it (unsurprisingly), so I looked into beat error correction.

It had a beat error of 9.1m/s (far too much), so I adjusted the beat error adjuster and got it down to 0.4m/s - But it was still running 28 s/d slow.

So, I adjusted beat error back and it is now running at -7s/d, but the beat error is 3m/s which I know is high.

I guess I have two questions.

1) Is 3m/s TOO high (In that it will cause issues down the line)
2) Is there a way to lower the beat error without increasing the inaccuracy or is this mismatch a sign of a deeper issue?

As I say, I'm very new to messing with the movement (certainly I'm not up to doing more than minor adjustments), so try and keep any answers to Infant school simplicity

Thanks.

M

[kildareman]

There's a good explanation of the relationship between rate/amplitude & beat error here https://wahawatches.com/watch-talk-w...or-of-a-watch/

[snowman]

There's a good explanation of the relationship between rate/amplitude & beat error here https://wahawatches.com/watch-talk-w...or-of-a-watch/

Thanks - I had seen that, but re-reading it this makes me wonder if I need to worry too much?

A watch with a high beat error can still keep accurate time if it has a strong amplitude and a consistent daily rate.

This seems to be my situation, so should I adjust forget about it for now?

M

[walkerwek1958]

What’s the amplitude like? Generally, the amplitude is the best indicator of the health of the movement.

If you set the beat error close to zero (0.2 will do) that'll get it in beat. Next step is to set the fine adjustor in the middle, then adjust the rate by moving the regulator. This will take a few attempts, but it should be possible to set it to around +/- 6 secs/day. Further fine tuning will be achieved using the fine adjuster (screwdriver slot), 1 gradation equates to 6 secs/day.

If the amplitude fully wound dial- up is below 260 degrees the movement isn’t in great shape and will benefit from stripdown, ideally it should be 290 or above.

First step before messing about is to demagnetise, forgot to mention that. Watches can be slightly magnetised, demagnetising will sometimes improve amplitude by 20 degrees. I used a cheap demagnetiser for a few years and it was fine.