Good amplitude, Near zero beat error, -195 s/d. What could be wrong?

[ColinC]

I am working on a watch with an ETA 2452 movement I bought on eBay.  When I got it the crown was stiff and it would only run for a couple of seconds after a good shake.

I have disassembled, inspected, cleaned, reassembled, lubricated, demagnetised.  It runs and I can regulate away any beat error but even with the regulator arm all the way across I can't get the watch to run fast enough.  It has a respectable amplitude and gives similar results in all 6 positions (slightly lower amplitude when not dial up or down).

 

The hairspring looks in great condition to me



Any ideas?

My only guess is that the balance is not the original?

Here is a slow motion video of it running (not sure this helps....)
 

 

[nickelsilver]

First thing I'd check is if the hairspring is correctly placed between the "boot" and regulator pin. Also if the regulator pin is possibly missing.

[Marc]

Assuming that you have carried out the checks outlined above by @nickelsilver one thing to note on these ETA's (and others) is that the regulator offers both coarse and fine adjustment.

The end with the graduations is the fine adjustment, but you will find that the other (boot) end can be moved independently.

I would center the fine adjustment end and then gently nudge the boot end until I got it as close to where I wanted it to be on the timgrapher, then fine tune with the graduated end.

[ColinC]

33 minutes ago, Marc said:

Assuming that you have carried out the checks outlined above by @nickelsilver one thing to note on these ETA's (and others) is that the regulator offers both coarse and fine adjustment.

The end with the graduations is the fine adjustment, but you will find that the other (boot) end can be moved independently.

I would center the fine adjustment end and then gently nudge the boot end until I got it as close to where I wanted it to be on the timgrapher, then fine tune with the graduated end.

I have checked and the hairspring passes nicely through the gap between the boot and the pin
And yes I have seen  movements where you can do that (the ST36 I bought to learn on for example) - but this isn't one of them. On this movement the boot end is on the same piece of metal as the pointer to the graduations.

I have done a little googling and found  some variety in the balance between different ETA 2452 movements - some have wheels with adjustable weights some have corse and fine tuning while mine seems to be very simple...

[nickelsilver]

1 hour ago, ColinC said:

I have checked and the hairspring passes nicely through the gap between the boot and the pin
And yes I have seen  movements where you can do that (the ST36 I bought to learn on for example) - but this isn't one of them. On this movement the boot end is on the same piece of metal as the pointer to the graduations.

I have done a little googling and found  some variety in the balance between different ETA 2452 movements - some have wheels with adjustable weights some have corse and fine tuning while mine seems to be very simple...

How big is the gap between the boot and pin? Should be just a little over the hairspring thickness.

[ColinC]

22 minutes ago, nickelsilver said:

How big is the gap between the boot and pin? Should be just a little over the hairspring thickness.

Pretty small - here is a photo (very hard to show!). But I don't think this is the problem as I can make the watch much slower by moving the regulator in the other direction

[Nucejoe]

1 hour ago, ColinC said:

But I don't think this is the problem as I can make the watch much slower by moving the regulator in the other direction

So its likely to be what you said, balance and hairspring aren't matched, which if is the case,

Unpin the hairspring from the stud.

Thread  about the length of the  current terminal curve through the stud.

Repin.

Turn the H/S collet to bring the balance complete in beat.

Regulate.

Do not cut the extra length of hairspring just yet.

Regulator slot looks good .

Good luck

Edited September 6, 2023 by Nucejoe

[Neverenoughwatches]

32 minutes ago, Nucejoe said:

So its likely to be what you said, balance and hairspring aren't matched, which if is the case,

Unpin the hairspring from the stud.

Thread  about the length of the  current terminal curve through the stud.

Repin.

Turn the H/S collet to bring the balance complete in beat.

Regulate.

Do not cut the extra length of hairspring just yet.

Regulator slot looks good .

Good luck

I'm interested in this, had the same problem a month back. Was convinced the hs wasn't matched up as everything else seemed ok so vibrated it to check and it was perfect. Reinstalled the balance to carry on investigating and then broke the new staff that i had just fitted. 

[ColinC]

Thanks - Though this might be the route I would need to take.

I don't own a staking set yet but have had some success with hand levers and hand pressing tools when experimenting with hairsprings (not sure I am ready to risk this watch yet)

Also not sure how to apply pressure without the risk of slipping to remove the existing pin

[Neverenoughwatches]

20 minutes ago, ColinC said:

Thanks - Though this might be the route I would need to take.

I don't own a staking set yet but have had some success with hand levers and hand pressing tools when experimenting with hairsprings (not sure I am ready to risk this watch yet)

Also not sure how to apply pressure without the risk of slipping to remove the existing pin

A handful of cheap watches to  practice with first colin, you'll be  removing and tweeking hairsprings in no time.

[Nucejoe]

2 hours ago, ColinC said:

Also not sure how to apply pressure without the risk of slipping to remove the existing pin

How about this, to remove the pin with,  $4.95 on ebay, have seen better items/ deals on  domestic portals in your part of the globe .

https://www.ebay.ca/itm/Mini-Small-Pliers-Precision-Jewellery-Craft-Long-Nose-Needle-Reach-Watch-Repair/142872771669?pageci=0aab0de0-c0c6-4f71-88bc-53be5b60d94f&redirect=mobile

 

 Need to say this as member  Franks being the knowledgable master watchmaker he is, settles for no less than perfect watch repair.

Going by the  prceedure I listed above, you can regulate to good degree of accuracy, but there is a bit more to this,  you can find articles on  CASPARI EFFECT which  has to do with isochronism,  I believe, there you are aiming at percision as well. 

Where for repining the stud do you think you need a staking set? 

Rgds

[Nucejoe]

Heres a pic of boot and pin.

Turn the boot to align with the pin so  hairspring can't jump out as it breaths.

Edited September 7, 2023 by Nucejoe

[Neverenoughwatches]

5 hours ago, Nucejoe said:

Heres a pic of boot and pin.

Turn the boot to align with the pin so  hairspring can't jump out as it breaths.

What a beautifully clean hs and regulator, why dont mine look like this when I've finished . Oh i know because nothing i have is less than 60 years old . I think Colin is worried about removing the brass stud pin to release the hs to shorten the length. Tricky little buggers they is, a pair of offset length leg tweezers to fit around the back of the stud and carefully tease the fixing pin out. Store it safe in a tiny white bottomed container like a contact lens case, unless you fancy making another one.

[Waggy]

I have had the opposite problem, I cant get the rate below +300 s/d . I guess I would need to lengthen the hs if there is any there to lengthen, else its a new balance?

Edited September 7, 2023 by Waggy

[ColinC]

2 hours ago, Waggy said:

I have had the opposite problem, I cant get the rate below +300 s/d . I guess I would need to lengthen the hs if there is any there to lengthen, else its a new balance?

My research has shown that this can be down to the hairspring effectively being too short due to magnetism or the coils touching as the hairspring breathes. 
Try a demagnetiser and check to see the hair spring is even and flat

[rehajm]

2 hours ago, Waggy said:

I have had the opposite problem, I cant get the rate below +300 s/d . I guess I would need to lengthen the hs if there is any there to lengthen, else its a new balance?

I have a Wittnauer 10T in one of the wife's watches with the same issue. Regulator moved all the way to R and I can see no no more hairspring left to re-pin the stud. How the hairspring stays in the stud I don't really know...

5 hours ago, Neverenoughwatches said:

What a beautifully clean hs and regulator, why dont mine look like this when I've finished . Oh i know because nothing i have is less than 60 years old

Ha- I haven't been using the ultrasonic for movement parts but tried it out the other day with a balance cock from an old movement I needed to re-clean. It looked brand new- those spots you get inside the screw holes I always assumed were exposed brass from the plating being worn off by the screws? Turns out it can be old...stuff. 

...I suspect the ultrasonic even cleaned the stud screw to like new condition. If I ever locate the screw I'll let you know...

Edited September 7, 2023 by rehajm

[ColinC]

Small update...

I managed to get the pin out but there was no way it was going back in again (too short to grasp and push back in).

Tried to make my own pin by rolling a some solid copper cable on a sharpening stone until it was the right size.  That nearly worked - enough at least for me to try once.

I managed to get the watch running again, this time much to fast.

Now waiting for some new pins I just ordered

[Nucejoe]

5 hours ago, ColinC said:

I managed to get the watch running again, this time much to fast.

How much of the effective length did you shorten? 

 Generally running too fast should be due to shortening too much of  the effective length of hairspring , however,  if you shortened about the length of terminal curve but runs much too fast,  there might be more than one issue invovled. Nevertheless, I try again this time shorten half the length you tried before. 

Good luck

 

[Drclock]

your timer - indicated 18000 bph

ETA 2412 actually runs at 21,600 - do not trust the auto settings 

[HectorLooi]

12 hours ago, Drclock said:

your timer - indicated 18000 bph

ETA 2412 actually runs at 21,600 - do not trust the auto settings 

I'm confused....

Yes, the ETA 2412 does run at 21600...

But aren't we talking about the ETA 2452 here?