Adjusting an ETA 2842

[qualitime]

I'm the happy owner of a PO 007 with an ETA 2842 in it.

It's the Swatch movement.

It's 40 sec. slow/day so I'm trying to adjust it.

On this movement there is no fine adjustment like in a 2836.

Instead of the fine adjustment there are markings +/- .

What do I have to move to adjust it?

It this one:

Thanks, Q.

[qualitime]

Anyone??

[freddy333]

Try this or use the Search.

[qualitime]

Thanks Freddy!.

Search didn't work. I was looking for that post.

First I've moved the "big" pin, watch was even more slow......

So moved that back and moved the verrrrrry little pin.

Now it's better! Still some fine adjustement to do.

Q.

[freddy333]

First I've moved the "big" pin, watch was even more slow......

So moved that back and moved the verrrrrry little pin.

Now it's better! Still some fine adjustement to do.

Unless you have a timing machine (or know how to ballpark the beat by movement of the balance), you should never/not move the larger arm. That 1 sets the beat. The smaller arm adjusts the length of the hairspring, which fine-tunes the speed of the movement (the longer the spring's effective length is, the slower the movement runs & the shorter it is, the faster the movement runs). Usually (if the movement is in proper working order), if you move the small arm closer to the larger arm, that will lengthen the spring & slow the movement. Conversely, if you move the small arm away from the larger arm, it shortens the spring & speeds up the movement. However, if the movement is out of adjustment, the small hand may have had to be set past the larger hand to offset a large deviation. In this case, the opposite may be true. And that may be the case for your watch. So make a very small change & then monitor the watch's accuracy over a period of several hours. If it is still off, make a corrective readjustment.

[qualitime]

Thanks again Freddy.

I have adjusted the watch now to +/- 0 (zero!) seconds over a day!

It's a harder job then adjusting a 2836 cause no fine adjustment screw.

I think I was very lucky!

Q.