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Posted
  On 4/12/2024 at 6:36 AM, VWatchie said:

There's no need to be condescending Frank. All I am trying to convey is that there is no risk of the stake reaching the hole in the balance when using a Platax tool.

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But that is a different pair of shoes, I never talked of that. I assume that the tool will not reach the hole, no matter what you use. Easy with simple stake, too, if you keep the stake between your fingers while hammering.
When I push the staff out after removing the hub, I use a stake with cylindrical pivot, a bit smaller than the hole.  

As I said, no punching method or tool can protect the hole 
- from widening by the distorted staff
- from distorting hole and balance arm to a funnel-like shape if the rivet is too thick (happened to me decades ago).

I apologize if I seemed to be condescending, tried to say it friendly, but meanwhile I am tired of repeating the facts. But I know now, we had different issues in mind.

Regards, Frank 

 

 

  • Like 3
Posted
  On 4/12/2024 at 1:03 PM, praezis said:

I apologize if I seemed to be condescending, tried to say it friendly, but meanwhile I am tired of repeating the facts. But I know now, we had different issues in mind.

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No worries Frank! I see where you're coming from and thanks for clarifying! 🙂

I would really hope someone, @Jon(!?) would make a video of how to punch out a staff using a staking set without first removing the hub or the rivet. Yes, Frank, you have clearly demonstrated that it is destructive, but for those of us who have no other option and are willing to risk it.

I haven't tried it but one dear WRT member whom we haven't seen in a long time, @HSL (anyone in touch with him?), recommended I try to remove as much as possible of the rivet before punching it out by using a razor-sharpened stake. Yes, I know, it is the hub that you must remove using a lathe, but at least I would think/hope that removing the rivet would be a step in the right direction.

  • Like 1
  • 2 weeks later...
Posted (edited)

Picking up this side-tracked post again as I just removed a balance staff of a 1920's Omega (35,5L-T1)

I was impressed by the way @Delgetti had his setup when he had to change out a balance-staff (https://www.watchrepairtalk.com/topic/28854-new-balance-staff-not-riveting-to-balance/page/2/#comment-244054

Not only that, but also the idea of removing the seat first before punching the staff out from the seat-side, avoiding the whole discussion of the rivet yes/no enlarging the hole.

I didn't have the fancy clamps & tools Delgetti has, so I used my screw-head polishing tool.

IMG_3814.thumb.jpeg.c6222840640ef04ee8901727bc98445c.jpeg

IMG_3815.thumb.jpeg.fcfc017c92a02c04cb9a2542a1bcdf19.jpeg

Initially I used #1500 grit diamond paste on the steel wheel, which kinda worked, but very slow. I changed to #800 grit diamond paste, which worked better, but still slow.

Then I glued #240 sanding paper to the steel disk;

IMG_3817.thumb.jpeg.5a425ea4918613f1710216cbab23a83f.jpeg

IMG_3820.thumb.jpeg.3f6c0f66987245f9b6251c841159ea6e.jpeg

That worked and the disk was hand-driven.

Once close to the balance wheel, I took the sanding paper off and continued with #800 diamond paste.

One can only do this when the balance wheel sits true on the staff and has no "wobble".

I went on grinding until I saw some diamond paste on the rim of the balance wheel. This was as far as I could grind and it seemed that at that point there wasn't much left of the seat.

IMG_3823.thumb.jpeg.e49e98c997352fa5d78490c90b819c85.jpeg

Carefully, with my staking set, I knocked the staff from the seat-side out.

Turns out that the thickness of the seat left, now a small ring, was only 0.1mm.

The balance wheel hole is in perfect shape and no damage done to the wheel at all.

IMG_3824.thumb.jpeg.158d8afa9f92e2224b0fb5e0587bbe3a.jpeg

Of course, if the wheel has a "wobble" or isn't seated true on the balance staff, you can't get as close and there will be more left of the seat.

In my case, it worked perfect 🙂

I'm very happy how this method worked out ! 😊

 

Edited by Endeavor
  • Like 5
Posted

This way is dangerous. The problem is that the collet is not expected to be perfect in this tool and the wheel used for the grinding is big and easy can touch the balance wheel. Can You show the bottom side of the balance wheel?

Posted
  On 4/27/2024 at 7:06 PM, nevenbekriev said:

The problem is that the collet is not expected to be perfect in this tool and the wheel used for the grinding is big and easy can touch the balance wheel

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The whole process and the progress are closely observed, it's hand-driven and very controlled. I can't see the "danger", unless you are watching the TV while doing it.

As you could have read,

  On 4/27/2024 at 6:01 PM, Endeavor said:

no damage done to the wheel at all.

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and in this quote "wheel" is the balance-wheel.

  • Like 1
Posted

I also see a bit of danger for the wheel, at least you have to keep away from it and may get a too thick rest ring. My rest rings are about 0.05 mm.

Better way would be a grinding wheel touching the staff with its circumference.

Frank

  • Like 1
Posted (edited)
  On 4/27/2024 at 6:01 PM, Endeavor said:

Of course, if the wheel has a "wobble" or isn't seated true on the balance staff, you can't get as close and there will be more left of the seat.

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Not having all the fancy equipment, this is a way I came up with. I never said it was the best, the most ideal or the safest way.

Working on balances is always a delicate task whereby full concentration & common sense should prevail.

I was well aware of the "dangers" / short comings involved, hence my "warnings", as quoted above.

The balance wheel of the Omega was nice true, flat and one could clearly see how much gap there was left before the grinding wheel would touch the balance wheel. I stopped when the generously applied diamond paste started to touch the rim of the balance wheel, which turned out to be with a seat thickness left of 0.1mm. Tapping the remainder of the staff out went easy and flawless.

My idea of penning this article was to show/share a way which, in my case, succeeded perfectly. If deemed to risky, or if the balance wheel is not true or has a wobble, other methods have to be followed (which BTW, as you can read in this thread, are rife with "dangers" as well)

Edited by Endeavor
  • Like 1
  • 4 months later...
Posted
  On 3/5/2024 at 6:00 PM, VWatchie said:

I watched the entire video again and I can't recall him mentioning that, but he does state that the Platax "breaks the rivet without damaging the balance wheel". Also, I think it is worth noting that there is a significant difference between punching out a staff using a staking set and using a Platax tool. When using a Platax there's zero risk that the punch reaches down to the hole in the balance as the punch is hindered from reaching that far. It is the very idea behind the Platax. I think the risk of enlarging the hole in the balance is minimal when using a Platax and no greater or even less than when riveting the new staff. Also, as I understand it, using a lathe to remove the rivet isn't foolproof either.

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If you look closely at the end result you will see that the staff is not centred. You can see side to side movement on the balance rim as it rotates. I think the hole in the balance wheel has got enlarged over the years as it's an old watch and has probably seen numerous staffs in its lifetime. Going through the same drama myself right now with an old watch and the slightly off centre hole has played havoc with the poise. Going to make it the best as I can by moving the rim weights to compensate.

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