Is it possible to straighten this pivot?

[Bill2024]

The pivot on this fourth wheel is bent and I was wondering if there is any way to straighten it?

Full disclosure - I think I did this taking it apart when I caught it on the movement holder when turning the movement over  

The movement does run, and it is possible to fit the seconds hand, but I imagine this is going to create all kinds of friction in the movement.

The fourth wheel is not jewelled on this movement. 

[AndyGSi]

First question would be could you get a replacement if it snapped?

Yes you should be able to straighten it but need to be careful.

I've found the best way is with a long piece of tube having a similar I/D to the O/D of the pivot.

[Bill2024]

1 hour ago, AndyGSi said:

 

First question would be could you get a replacement if it snapped?

 

Probably - the movement is an old Oris 581 kif, so not rare or valuable, but I must say don’t see many of these on eBay. I see lots of other vintage oris calibres but I don’t know if any of the parts would be compatible.

Is it possible to look up which Oris movements might have a compatible fourth wheel anywhere?

1 hour ago, AndyGSi said:

Yes you should be able to straighten it but need to be careful.

I've found the best way is with a long piece of tube having a similar I/D to the O/D of the pivot.

Thanks I think it’s worth a try. Can you suggest what type of tube might be useful for doing this?  I thought about trying a pin vice but that seems a bit clumsy. 

[VWatchie]

17 minutes ago, Bill2024 said:

Is it possible to look up which Oris movements might have a compatible fourth wheel anywhere?

I just had a look w/o luck...

Here's a decent database too: https://www.emmywatch.com/db/movement/oris--581/

Edited Saturday at 06:43 PM by VWatchie

[Mark]

Its risky but sometimes do-able.

I showed a technique in one of my old videos...

Go to 0:46 (46 seconds in)..

Be very careful

Hope that helps.

[AndyGSi]

They're available from Cousins but appear to be a one movement only part.

I've got a selection of stainless steel tube.

You'll also need to support the other part of the shaft to make sure you're only bending the pinion.

[Bill2024]

2 hours ago, Mark said:

Its risky but sometimes do-able.

I showed a technique in one of my old videos...

Go to 0:46 (46 seconds in)..

Be very careful

Hope that helps.

Thanks @Mark I think the pin vice to hold the wheel and rolling the pivot in the staking block could work if I take it steady. Will give it a go  

2 hours ago, AndyGSi said:

They're available from Cousins but appear to be a one movement only part.

I've got a selection of stainless steel tube.

You'll also need to support the other part of the shaft to make sure you're only bending the pinion.

That’s great thanks very much. 

2 hours ago, VWatchie said:

I just had a look w/o luck...

Here's a decent database too: https://www.emmywatch.com/db/movement/oris--581/

Thanks for the links. It’s always good for me to add to my growing list of resources. 

[nickelsilver]

I straighten pivots like this routinely. Get the part running true in the lathe, not counting the pivot. Heat brass or nickel tweezers in alcohol lamp until you can barely hold them, and use them to coax into alignment.

[HectorLooi]

16 minutes ago, nickelsilver said:

Heat brass or nickel tweezers in alcohol lamp until you can barely hold them

That is around 60-70°C, depending on how thick-skinned your fingertips are.

I've always wondered if that really helps. It isn't hot enough to temper steel.

Is it only to allay our fears of breaking of the pivot? And if the pivot breaks, we can console ourselves that we had tried our best.

I normally put my soldering iron tip, set to 250°C, at the point where I wish to bend the pivot and heat it for about 30 seconds.

Does that work? Honestly, I don't know. But at least that is at tempering temperature range. 

Have I broken any pivots trying to straighten them? Sure! But at least I've tried my best. 

[nickelsilver]

7 hours ago, HectorLooi said:

That is around 60-70°C, depending on how thick-skinned your fingertips are.

I've always wondered if that really helps. It isn't hot enough to temper steel.

Is it only to allay our fears of breaking of the pivot? And if the pivot breaks, we can console ourselves that we had tried our best.

I normally put my soldering iron tip, set to 250°C, at the point where I wish to bend the pivot and heat it for about 30 seconds.

Does that work? Honestly, I don't know. But at least that is at tempering temperature range. 

Have I broken any pivots trying to straighten them? Sure! But at least I've tried my best. 

It's a good question.

 

I was taught by old dudes to heat the living sh!t on my tweezers. The go-to were Dumont #8, and they are listed for exactly this use.

 

They work great (heated) for larger pivots like extended 4th wheel pivots.

 

For something like a balance pivot the #8 will pretty assuredly make some marks or flats. I do use them, but most of the time stick to brass/nickel  with stout tips. I've tried going without heat, and broken more pivots. It isn't anywhere near tempering temperature, but it really does make a huge difference.

[nevenbekriev]

I can for sure say that heat, transferred to the pivot is much less than the heat temperature of the tool. for example, soldering (heating) of steel with soldering iron, heated to 300 degr., doesn't make the steel part change it's color. This means the part doesn't heat even to 200 degr. Soldering doesn't temper the hardened steel parts. But yes, the heating, even without tempering, helps.

The pivot on the picture will get straighten without heating, at least with 90% probablity. But I don't care if it breaks as repivoting takes 10-15 min

[Curare]

On 5/11/2025 at 3:03 AM, Bill2024 said:

Full disclosure - I think I did this taking it apart when I caught it on the movement holder when turning the movement over

On a side note, I always leave the canon pinion on to help protect the seconds hand pinion, it is generally the last part I remove when dismantling a movement 

[rehajm]

2 hours ago, nevenbekriev said:

But I don't care if it breaks as repivoting takes 10-15 min

[mbwatch]

3 hours ago, nevenbekriev said:

But I don't care if it breaks as repivoting takes 10-15 min

What do you use as pivot drills @nevenbekriev?

[nevenbekriev]

5 hours ago, mbwatch said:

What do you use as pivot drills @nevenbekriev?

Search 'PCB carbide drill bits'. They come in sets of 10 or 50 and have 3.175mm tail. They are cheap rather than affordable. Using this drill bits has been discussed here many times - they are longer than needed and easy to break, so it is useful to practice sharpening hem and drilling some useless parts to gather some experience before real work.

[Neverenoughwatches]

I buy these from AliExpress now, if in the UK they are extremely cheap. I shorten them first by breaking them to half length or less, and then re-sharpen them, as Nev said they are much too long for re- pivot work and can break easily.