regulating the fine etacrhon ?

[horologist]

My eta 2836 has been losing between 5 to 10 seconds per day.  With the older etas, one had the lever which you moved left and right all depending on if you wanted to gain or lose time.

 

I noticed that with the modern eta 2836 wish bone, there is a screw with one end that is open and the other end closed.  I know that each increment on the adjuster is for +/- 5 seconds.

 

I tried to move this screw in the + direction but somehow no amount of force will turn this screw.

 

As this is the first time I am attempting this, I don't want to cause uneccessary damage,  I am wondering if this screw is meant to be turned at all, seeing that it just wont' turn  Many thanks in advance!!!!

[GenTLe]

Normally it can be used. But, for example, I've a 2836 for witch that screw is totally useless (it rotates but no changes in the regulation).

You can always remove the autobridge and work on the coarse regulation arm.