ETA2801-2 low amplitude, running slow

[scarab]

Hello,

I have a problem with my ETA2801-2. Initially the watch was running great, but it was skipping while winding. I guess I made a mistake and pulled the train bridge in order to check the mainspring, afterwards I figured that wasn’t necessary. Anyway, after putting everything back together it was running with low amplitude and became impossible to regulate to anything over -120spd. I decided to pull the bridge again, and clean all associated parts in ultrasonic, and re-lubricate. Unfortunately nothing has changed, it still runs with low amplitude - about 230 and there is no way to make it run any faster than -120spd. What could be the reason behind it? Here is how it looks like on a time grapher. 

[clockboy]

Is the hairspring in between the regular pins

[Nucejoe]

 Apparently you are sure you had better amplitude before. As Clockboy says, hairspring out of  regulator slot slows  the rate but you should get larger amplitude instead. 

Something might be rubbing,  barrel lid is to sit flush level at wall of the barrel, all arbours should have a little free play, very specially balance staff. in case end stomes are slightly pushing on pivots, you get low amplitude and slow rate.

If adjustment of the pallets aren't anything to be proud of, then oscilation can be poor. Did you put the fork or balance in ultrasonic too? 

Regs 

Joe

 

[scarab]

Before I put my hands on it it was running great, with +-3 spd and correct amplitude so I definitely messed up or broke something. The only problem it initially had was skipping while winding. It still has problem with winding but I bet that’s caused by winding yoke. In order to isolate the issue I removed the clutch/crown wheel and wound it with a screwdriver. I’m not sure if the clickspring provides the correct tension but that shouldn’t be causing amplitude/accuracy issues, correct? 

Yes, I put the balance and the fork in ultrasonic as well. 

[JohnR725]

we really need a decent picture of the balance wheel assembly in the watch. Preferably at multiple angles like one straight down  then one at a angle so we can see if they hairspring is flat in the regulator etc. 

[scarab]

Please take a look. I took them with the mainspring released. I can also pull the balance and take some pics outside the watch if that would help.

Edited September 17, 2021 by scarab

[Nucejoe]

 What cleaning solution is in your ultrasonic?   The shellac that holds pallet jewels intact can get washed away in ultrasonic, same with impulse jewel, pallet will then move in fork slot which can cause all symptoms you mentioned. 

[scarab]

I did Zippo lighter fluid for the wheels, bridge, balance and fork and then followed with IPA for everything except balance and fork as I was concerned about shellac  It’s not about the wash as it was behaving exactly the same after I reassembled it for the first time, before I did the wash.

[Nucejoe]

The hairspring appears to be inside the regulator slot.   The stud ,however, is been pushed down, that should cause  hairspring coil unlevel, though not enough to cause the hairspring rub on the cock.

[Nucejoe]

Sorry zippo or Ronson lighter fluid are not shellac friendly in ultrasonic, you are likely to have lost all shellac there and pallet or impulse jewel might have moved. 

[Nucejoe]

6 minutes ago, scarab said:

I did Zippo lighter fluid for the wheels, bridge, balance and fork and then followed with IPA for everything except balance and fork as I was concerned about shellac  It’s not about the wash as it was behaving exactly the same after I reassembled it for the first time, before I did the wash.

I see. So what is the end shake on balance staff.

[scarab]

Dang, I didn’t know that, I hope I haven’t ruined it. Then what is the best affordable cleaning solution for balance and pallet fork? 

 

Edited September 17, 2021 by scarab

[Nibbler]

can you take the balance bridge off, flip it upside down from the pictures here take a picture and post?

Matt

 

[scarab]

Here it is. Sorry, I don’t have a macro lens and had to improvise with my phone and a loupe.

 

[rodabod]

Are you by any chance trying to regulate using the fine regulator adjustment rather than move if the arm which carries the index pins directly?

[Nucejoe]

5 hours ago, scarab said:

Dang, I didn’t know that, I hope I haven’t ruined it. Then what is the best affordable cleaning solution for balance and pallet fork? 

 

Lighter fluid is OK if you are cleaning by hand, but not in ultrasonic. I discovered that the expensive way.

As for cleaning solutions there is a very very long thread right on this here forum, more helpful than I can possibly be in one post.

Regs

[Nucejoe]

Some balance pivots tend to vanish in ul1trasonic, some don't.

 

[scarab]

47 minutes ago, rodabod said:

Are you by any chance trying to regulate using the fine regulator adjustment rather than move if the arm which carries the index pins directly?

I tried both. I can go slower by regulating with the arm but not much faster than -120spd. 

[scarab]

3 minutes ago, Nucejoe said:

Some balance pivots tend to vanish in ul1trasonic, some don't.

 

Well, I hope I was lucky this time. I already let this watch run for a couple of days hoping the amplitude will get better. I haven’t noticed any improvement but at least it didn’t got any worse so maybe shellac is still in place. I will take your advice and do some more research. I was aware IPA is a no go for balance, just didn’t know about lighter fluid. 

[ifibrin]

2 hours ago, Nucejoe said:

Some balance pivots tend to vanish in ul1trasonic, some don't.

 

Wait what? Do you mean the pivots vibrate against the containers so fast due to the ultrasonic they snap off?

Edited September 18, 2021 by ifibrin

[ifibrin]

2 hours ago, scarab said:

Well, I hope I was lucky this time. I already let this watch run for a couple of days hoping the amplitude will get better. I haven’t noticed any improvement but at least it didn’t got any worse so maybe shellac is still in place. I will take your advice and do some more research. I was aware IPA is a no go for balance, just didn’t know about lighter fluid. 

Have you checked all the jewel holes for dirt, and pivots to see if they are fine? Since you only had the issue after disassembling, and reassembling before cleaning (and even after cleaning and re-lubrication) it doesn’t seem to be due to oiling. Maybe something got caught in the jewel hole, or one of the pivots got damaged?

[Nucejoe]

4 hours ago, ifibrin said:

Wait what? Do you mean the pivots vibrate against the containers so fast due to the ultrasonic they snap off?

The mere vibrations destroy pivot hanging in solution. No need to vibrate against anything.

Regs

[rodabod]

Can you check the end-shake of the balance? Let down the mainspring and then grab the rim carefully and lift/drop. 

I’ve seen jewel holes move when cleaning in the past. 

[rodabod]

when I said “jewel hole” above, I meant to say chaton as this is a shockproof setting.

Also, in your two timegrapher photos, is one dial-up and the other dial-down?

 

[ifibrin]

10 hours ago, rodabod said:

Can you check the end-shake of the balance? Let down the mainspring and then grab the rim carefully and lift/drop. 

I’ve seen jewel holes move when cleaning in the past. 

If you are test the end-shake of the balance in this way, wouldn't you only be able to see the (potential) movement of the jewel hole on the balance cock side? Seems quite difficult to manipulate the balance wheel if the dial side of the movement is facing up.