Omega 601 - haywire running in DU to 12 up positions.

[hofnerpres]

The last two old watches are refusing to get well easily. Manual wind Omega 601 in clean nick. Second had had been ripped off and the shaft snapped. Replacement fitted and it only took the usual three goes to get that friction spring screw to start before it dropped in the movement. Would it have killed Omega to give us a pointed lead-in screw and a bit more depth.....? Bad enough they went for the bodge of fitting a free driven shaft which the had to to be restrained. Can you tell I'm having a bad morning ? Anyway, straightforward service and new mainspring. Ran well enough to get me test wearing and regulating. Third day we are not happy DU or anywhere between that and 12 up. Looses the plot at minus 150 s/day and crazy beat error. All other positions are 230 and sub 0.5 beat error with a nice clean trace. I'm thinking balance spring well out of poise. Spring is flat and looks central. It;s not rubbing the cock or even close. Try the usual slight manipulation to vary the placement of the spring in the regulation pins. Makes only slight differences. Problem remains. Remove balance from the cock and all looks very well positioned. Before I get the spring off and double check the poising any thoughts ? I've reshaped and repoised a few balances in my time but this seems a bit extreme behaviour from such a good looking spring. See pic.

[JohnR725]

5 hours ago, hofnerpres said:

Anyway, straightforward service and new mainspring. Ran well enough to get me test wearing and regulating.

Sounds like everything is fine here? I assume you follow some sort of standard testing procedure? Like dial-up and dial down and crown down perhaps? Following proper timing procedures and writing down the numbers possibly taking pictures is nice when problems pop up later on as you have a reference of what it looks like before.

5 hours ago, hofnerpres said:

Third day we are not happy DU or anywhere between that and 12 up. Looses the plot at minus 150 s/day and crazy beat error. All other positions are 230 and sub 0.5 beat error with a nice clean trace. I'm thinking balance spring well out of poise.

You didn't say what the amplitude is in the bad position I'm guessing it's very. Then all other positions which ones exactly? Then thing that could cause this would be the balance pivots or the jewel setting. Basically it sounds more like a pivot issue.

Then usually Omega does a really nice job of poising the balance wheels anyway I seriously doubt it's a poising Problem. Besides poising problems don't show up on the ends of the pivots are typically show up in the crown positions. So it's not a poising problem

5 hours ago, hofnerpres said:

I've reshaped and repoised a few balances in my time but this seems a bit extreme behaviour from such a good looking spring.

When you're new to watch repair you really need to slow down What you are doing. Or find a cheaper watch to learn on because you don't want to screw up your balance wheel it's going to be expensive

[hofnerpres]

Wish l was new to the game John but after 15 years and some 200 watches from Rolex to hmt l can only hide behind incompetence. At 75 years old time is running out ! The amplitudes DU and moving to 12 up were around 150 degrees with 9.9 beat error . Healthy 230ish in all the other positions. Something must be catching or pivots doing odd things. Shakes are all good. Really baffling.

[JohnR725]

1 hour ago, hofnerpres said:

Wish l was new to the game John but after 15 years and some 200 watches from Rolex to hmt l can only hide behind incompetence. At 75 years old time is running out !

I typically don't read introductions from newbies. I only look at the question and try to Help with a answer so for the question somebody's working on the Omega which newbies shouldn't do because the cost and yes people new to the group work on Rolex watches most of the time they succeed eventually some do better than others.

If you're really hiding behind incompetence then you're screwed. The problem of working on Rolex watches are it requires a different skill set than working on a vintage watch. For instance with a vintage you can have a problem like you're having now you probably wouldn't have that problem with the Rolex watch. So basically you're not experience with working on the watches are doing right now so let's see what can do to help with that.

1 hour ago, hofnerpres said:

The amplitudes DU and moving to 12 up were around 150 degrees with 9.9 beat error . Healthy 230ish in all the other positions. Something must be catching or pivots doing odd things. Shakes are all good. Really baffling.

The beat error is not a problem it's just fine. As the amplitude drops everything gets magnified so until we get the amplitude back up things will look much much worse so don't worry about it.

9 hours ago, hofnerpres said:

Ran well enough to get me test wearing and regulating.

Typically when I'm servicing vintage watches I like to not case them up for a day or two. If you're working on modern watches you'll have a habit of casing up the watch because you're going to assume it's going to run fine vintage you can never assume anything other than you just shouldn't assume things happy and good. So I assume the watches cased up right now?

Casing up a course introduces new problems like the hands hitting something on the dial side and we can't see the dial side because of dials there any way.

Then unfortunately I can't mentally get a picture of this watch and I can't find a good picture of what I'm looking for online. One of these you want to look at is the balance wheel and see of it looks like it's touching anything. If you end up with too much end shake you might be rubbing on something. On one occasion at work somebody was having an issue with.remember what balance arm was rubbing on one of the pallet screws it would just a tiny bit loose and do certain position it would touch.

Worst-case you'll have to start disassembly. I would want to look really carefully at the balance jewels and see how the pivot looks in the jewel which is a set of the dials on will present a problem.

Oh and if it is case up in the position it's giving you a problem visually can you see the problem exists? I has what a make sure that your holding them if it's cased up correctly because sometimes the timing machine can have issues picking up watches if there cased up sometimes things will look worse when they're not really worse.

 

[Nucejoe]

Impulse jewel rubbing on the fork is a possibility.

A side view vid  of the oscilator when running ,  in DU position helps.

 

 

[hofnerpres]

High folks. I had the escapement apart and found a tiny piece of lint hiding around the escapement wheel. I could not see thus even under the microscope. Problem now gone away and running to 2 secs a day when worn. Thanks again.

[hofnerpres]

Oh dear - The watch came back. Developed a tendency to stop after 12 hours and checking on the Timegrapher we have 185 amplitude DU and similar DD etc - this thing is not happy. So we go back to basics and go systematically from the barrel upwards. There was a little side wear on the barrel arbor hole - very slight but I closed this up with my staking set and got it broached out. No change. Barrel arbor runs freely and little wear apparent. Assemble the train wheels after getting their pivots under the microscope - all clean,true and shiny. All run freely. No change. Pallet guard pin looked very slightly bent down - on this balance design that should not foul anything but made sure it was straight and true. ( The Omega 600 series is very slim and impossible to get photographs or see in this area when assembled )At this point the amplitude increased slightly - interesting. I gave the impulse jewel a test with the tweezers in case it was starting to become loose - looks good but under the microscope there was a slight discolouration. Could this be some coating I had not noticed ? Gave it another good Rodico and clean and hey presto, We have 235 degrees at DU and half wind with a clean trace. So, what have we learnt ? Poor initial observation on my part and sometimes normal cleaning will not shift every deposit. Vintage watches need closer examination and methodical diagnostic skills - they are endlessly entertaining.....

[CYCLOPS]

since you found lint in the watch {original problem}, maybe you should just re-clean to be safe.....