Going out of mind here with low amplitude on a 7s26 and can't fathom why. ANY suggestions for fault finding would be great. I'm ready to throw in the towel.

[Birbdad]

So this is like my...8th service on a 7s26. These usually take me three hours, i get great deltas, 270 amp, i can do these in my sleep. 
My favorite dive watch was long overdue for a service. The only thing different here was I was going to try a generic mainspring for the first time and service a barrel for the second time. The mainspring i used is a general resortes 2377X which according to many here is correct for this movement and should have no problem getting me to 270 amp. Here's what i've tried and here were my results. 

1. Lubed it and put it together, was only getting 220 amp but clearly getting premature bridle slipping. 
2. Cleaned and relubed, reserviced the barrel, used less braking grease. Gained about 10 degrees of amp. 

3. Cleaned and relubed, reserviced the barrel, used more braking grease but spread it about in a ring. Got me up to 250 and even 260 at one point, almost there, and i can stop fretting whether that mainspring has enough juice. 

4. Took apart, noticed my balance and pallet fork rusted to crap due to likely moisture ingress into my bench solvent. Sucks, but i got spares and hey now it should all be working right? Surely a rusty pallet fork/balance staff (REAL RUSTY) is gonna drag my amp down.

5. Today, took apart, cleaned put in new pallet fork and balance and swapped the escape wheel for a brand new one, METICULOUSLY lubricated under the scope so i could be sure it was perfect so i wouldn't have to do it again. I just finished and put it on the grapher....somehow replacing a rusty pallet fork and balance LOST me 70 degrees of amplitude and i'm barely hitting 170. 

This is a borderline brand new looking movement. It worked GREAT when i took it apart. I had no mishaps, everything seems perfect under inspection. Pros in here. where on earth would you start fault finding here? one thing I've never gotten on these seiko movements is back lash. Put the power train in, spin the barrel, the wheels should spin and then be pushed the opposite direction a bit. I've never really gotten that even on services that turned out perfect but maybe it's an indicator something's wrong this time. The balance wiggles and moves totally freely with no wind, it does not feel like something is obstructing the power train at all. 

 

ANy ideas of where to start with this? I'm just losing it here

[AndyGSi]

Is it an A, B or C?

How does the balance operate without the pallet fork?

Have you got another complete barrel with spring to try?

I think the GR2378X is a nearer match for the mainspring but isn't that much different to the GR2377X

[Birbdad]

15 minutes ago, AndyGSi said:

Is it an A, B or C?

How does the balance operate without the pallet fork?

Have you got another complete barrel with spring to try?

I think the GR2378X is a nearer match for the mainspring but isn't that much different to the GR2377X

It's a B. Which always seem to be the most problematic
And what do you mean how does the balance operate without it? As in does it spin freely? If thats' what you mean then yes.

And i do not have another complete barrel. I swapped all the barrel parts to troubleshoot that earlier. this one is pristine.

EDIT: Okay. i probably figured out what's going on but i'm utterly baffled as to how it got there. The moisture ingress that caused my old pallet fork to rust...i think it corrupted my bench solvent (perchloroethylene) and has caused some reaction with it that it deposited an invisible waxy substance all over my balance. It's invisible but i just scraped it with a piece of pegwood and it's thick and is not desolving in more perc nor did it desolve in a precleaning of naphtha with a q tip. 

That substance is probably on my pallet fork AND my balance cock....I have no idea what it is or why the bench solvent i've used for years is suddenly depositing it. 

I'm gonna try cleaning everything AGAIN, and this time put my balance on the mainplate and my pallet fork through my normal wash procedure. I

I'll report back. Can water cause a weird reaction with these solvents?!

Edited August 6, 2024 by Birbdad

[AndyGSi]

13 minutes ago, Birbdad said:

And what do you mean how does the balance operate without it? As in does it spin freely? If thats' what you mean then yes.

The main question here is how long does it spin freely? Is it just a couple of oscillations?

As you've already found you're potential problem I'll leave it with you.

[Birbdad]

2 minutes ago, AndyGSi said:

The main question here is how long does it spin freely? Is it just a couple of oscillations?

As you've already found you're potential problem I'll leave it with you.

It's possible, i've had so many strange problems pop up i got a feeling this isn't gonna solve it entirely. 

For starters my rate with a brand new balance spring with the time regulator in dead center is somehow 180 seconds a day...a waxy film can't account for that. I have no clue what is going on. I'll leave the thread up just so i can go back to it or maybe just say all the lessons i've learned with this disaster of a service.

[Neverenoughwatches]

40 minutes ago, Birbdad said:

It's possible, i've had so many strange problems pop up i got a feeling this isn't gonna solve it entirely. 

For starters my rate with a brand new balance spring with the time regulator in dead center is somehow 180 seconds a day...a waxy film can't account for that. I have no clue what is going on. I'll leave the thread up just so i can go back to it or maybe just say all the lessons i've learned with this disaster of a service.

Personally i would go right back to basics. Check and change solutions,  clean the movement and parts throughly . Test the function groups seperately and then interactively working towards the escapement. 

[Birbdad]

3 hours ago, Neverenoughwatches said:

Personally i would go right back to basics. Check and change solutions,  clean the movement and parts throughly . Test the function groups seperately and then interactively working towards the escapement. 

I'm on round 4 of that haha. But this weird residue, this has to be it this time and this has exposed a hazard in my cleaning routine. I'm going to stop cleaning shellacked parts in perc, use ipa as my bench solvent just for jewels and clean my balance and pallet fork in my normal wash. 

Also gonna test the shellac vs ipa thing with a busted pallet fork i got and i'll share my results in another thread. I got all the people here saying yes, ipa destroys the stuff. All the people at my other place saying absolutely it doesn't destroy shellac unless you soak it in it for several days or basically boil the ipa. 

Now i'm curious.

[Jon]

15 minutes ago, Birbdad said:

Also gonna test the shellac vs ipa thing with a busted pallet fork

Try IPA and compare it to denatured alcohol, or what we call methylated spirits. Methylated spirit is what i use to dissolve shellac, as it is mainly ethanol with about 10% methanol, IPA will dissolve shellac, but at a slower rate to meths.

I'd be interested in the results of your experiment

[Neverenoughwatches]

4 minutes ago, Birbdad said:

I'm on round 4 of that haha. But this weird residue, this has to be it this time and this has exposed a hazard in my cleaning routine. I'm going to stop cleaning shellacked parts in perc, use ipa as my bench solvent just for jewels and clean my balance and pallet fork in my normal wash. 

Also gonna test the shellac vs ipa thing with a busted pallet fork i got and i'll share my results in another thread. I got all the people here saying yes, ipa destroys the stuff. All the people at my other place saying absolutely it doesn't destroy shellac unless you soak it in it for several days or basically boil the ipa. 

Now i'm curious.

I also used perc but stopped for some reason, might have been this residue thing you're experiencing Col. or maybe it just didn't degrease very well, cant remember. Still variables to consider with the IPA , what sort of machine are different people using ? Alex Hamilton experimented with using an ultrasonic to clean pallet forks , his results were pretty conclusive that the cavitation bubbles removed the shellac from them and in most cases dislodged the pallet stones. Pallet fork and balance I've cleaned manually for ages now, this means i have more control over what happens to them. If the hairspring needs cleaning more so then i use a very simple vibrating macine that doesn't produce cavitation bubbles in the water it contains. If that isn't enough then i would pull the hairspring and clean it by itself in a small us machine .

3 minutes ago, Jon said:

Try IPA and compare it to denatured alcohol, or what we call methylated spirits. Methylated spirit is what i use to dissolve shellac, as it is mainly ethanol with about 10% methanol, IPA will dissolve shellac, but at a slower rate to meths.

I'd be interested in the results of your experiment

Same experience here exacly Jon.

[Birbdad]

21 hours ago, Jon said:

Try IPA and compare it to denatured alcohol, or what we call methylated spirits. Methylated spirit is what i use to dissolve shellac, as it is mainly ethanol with about 10% methanol, IPA will dissolve shellac, but at a slower rate to meths.

I'd be interested in the results of your experiment

Yeah, there's this discrepency. The people at my other watchmaking space which has a lot of active pros too, not one of them says ipa will damage your shellac unless you basically boil it, and here which also has active professionals not one of them say it doesn't damage it. 

All agree denatured alchol is bad news for it though. 

Interestingly, i did a very poor attempt of gluing an arbor to my bench block the other day with shellac and burned the shellac turning it almost black. It was all over my arbor. I threw it in denatured alcohol for 3 days and not a single micron of it dissolved in it.

[AndyGSi]

13 minutes ago, Birbdad said:

Yeah, there's this discrepency. The people at my other watchmaking space which has a lot of active pros too, not one of them says ipa will damage your shellac unless you basically boil it, and here which also has active professionals not one of them say it doesn't damage it. 

All agree denatured alchol is bad news for it though. 

Interestingly, i did a very poor attempt of gluing an arbor to my bench block the other day with shellac and burned the shellac turning it almost black. It was all over my arbor. I threw it in denatured alcohol for 3 days and not a single micron of it dissolved in it.

So if IPA doesn't dissolve Shellac, how come they make French Polish with IPA & Shellac?

[Birbdad]

4 minutes ago, AndyGSi said:

So if IPA doesn't dissolve Shellac, how come they make French Polish with IPA & Shellac?

Hell if i know haha. I don't know what to believe at this point. Hence why i'm gonna science it up with a pallet fork that's already busted. Apparently ALL fo them and their professional workplaces and schools almost have ipa for at least one stage of their rinse cycle.

 

[caseback]

On 8/6/2024 at 6:03 PM, Birbdad said:

Also gonna test the shellac vs ipa thing with a busted pallet fork i got and i'll share my results in another thread. I got all the people here saying yes, ipa destroys the stuff. All the people at my other place saying absolutely it doesn't destroy shellac unless you soak it in it for several days or basically boil the ipa. 

Now i'm curious.

IPA does dissolve shellac, but it takes a while. You use it to make a liquid shellac, which can sometimes be easier to use if you're not in a hurry. 

[Birbdad]

Okay, looking for ANY fault finding suggestions. I don't want to give up on a watch but i'm getting pretty damn close here.

Recleaned, re-oiled for the FIFTH time, took my time with it, extra careful. I cleaned the jewels and balance and pallet fork with my normal cleaning routine, THEN cleaned them with acetone to make sure whatever that residue my solvent put on them was gone, it appears to be, then ran them through my cleaning procedure again. It's all spotless i really took my time. Mainspring appears to get a full wind 

Can't break 200 amp in dial positions. 

ANy suggestions where to start fault finding? I can post graph pics when it settles in.

[AndyGSi]

If you're confident about it being clean and assembled correctly then I'd look back at what spring you got.

[Birbdad]

17 minutes ago, AndyGSi said:

If you're confident about it being clean and assembled correctly then I'd look back at what spring you got.

So at one point in this debacle i was running the thing with a pallet fork and balance tha twas COMPLETELY rusted with the same spring and that dragged my amp down to only 255 to 260. 

WHere i'm at now is i swapped the pallet fork out for another that looks basically brand new  and put a new balance in and that dropped the amp a full 80 degrees. 

I'm pretty sure i've troubleshot the barrel service and the spring at thisi point.

[AndyGSi]

So if you're confident that the spring you've fitted is correct then what about the pallet and balance.

Where are these from?

[Neverenoughwatches]

22 minutes ago, Birbdad said:

So at one point in this debacle i was running the thing with a pallet fork and balance tha twas COMPLETELY rusted with the same spring and that dragged my amp down to only 255 to 260. 

WHere i'm at now is i swapped the pallet fork out for another that looks basically brand new  and put a new balance in and that dropped the amp a full 80 degrees. 

I'm pretty sure i've troubleshot the barrel service and the spring at thisi point.

Theres been a lot of swapping of pallet forks and balances. I'd be looking at their interaction with each other, too much depth of lock can kill amplitude. 

[Birbdad]

20 minutes ago, Neverenoughwatches said:

Theres been a lot of swapping of pallet forks and balances. I'd be looking at their interaction with each other, too much depth of lock can kill amplitude. 

Yeah my other group says the same. I'd be surprised if this was the case as i've not only swapped out all those parts in the past but have entire watches cobbled together from just spare 7s26 parts but i got some junk movements  i can pull spares of dubious condition out of to test and see if there's any change in behavior.

I know that all three versions of this movement use the same pallet fork so there shouldn't be any issues but ya never know.

[AndyGSi]

Pallet fork are interchangeable but balances aren't.

[Neverenoughwatches]

39 minutes ago, Birbdad said:

Yeah my other group says the same. I'd be surprised if this was the case as i've not only swapped out all those parts in the past but have entire watches cobbled together from just spare 7s26 parts but i got some junk movements  i can pull spares of dubious condition out of to test and see if there's any change in behavior.

I know that all three versions of this movement use the same pallet fork so there shouldn't be any issues but ya never know.

Maybe its worth just posting a photo of the depth of lock on both stones.

[Birbdad]

8 hours ago, Neverenoughwatches said:

Maybe its worth just posting a photo of the depth of lock on both stones.

I can do that. Also had a weird development that hasn't happened yet. Woke up and the thing was stopped after running for only 10 hours. 

Gave the balance a puff and it started right up again. Something between the barrel and the balance is REALLY dragging this thing down.

[Birbdad]

@Neverenoughwatches

[Neverenoughwatches]

30 minutes ago, Birbdad said:

@Neverenoughwatches

To my untrained eye ,especially on Seiko would say it looks too deep, a good third. I couldn’t say how much amplitude this would rob or if its enough to stop a watch before the power reserve ran out . A comparison with a known good amplitude watch might indicate.  Still think function group testing will zero you in on the fault.

[rjenkinsgb]

Are you lubricating the pallet fork pivots as part of your rebuild? That may reduce amplitude?

And the impulse jewel faces? That may also affect it, but better if done.