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Posted (edited)

I have the opportunity to buy a lovely Longines watch but I'd like to know if this is an easy fix. Seller only says that a screw is missing from the oscillating weight and that that's why it's not installed on the movement.

I'm not sure how this one works and how it stays on the movement and I also feel like I see a screw on the weight in the picture. Could someone shed some light on this ? Should the weight have another component that goes into the slot or is just a screw necessary ?

There is a screw on the weight near the movement and I see it in the picture but I assume that's not what we're talking about...

Also, is this even a cal 291 or something else ?

Is the circle in the bag, around the weight, even part of all this ? Could it be some sort of a ring for the movement ? Doesn't seem like it...

20170923_094937.jpg

Edited by Chopin
Posted

It is a calibre 291 the rotor sits on a post at the centre of the movement and the screw on the rotor is used to secure it to the post. It is probably the rotor post that has broken, these are listed as obsolete on the cousins web site, it is a common problem with this movement I dont know if any other supplier would hold this particular part. The ring looks like a tension ring from a watch crystal and is not a part of the movement such as a movement spacer ring as this one is held in place with clamps

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Posted (edited)
9 minutes ago, wls1971 said:

It is a calibre 291 the rotor sits on a post at the centre of the movement and the screw on the rotor is used to secure it to the post. It is probably the rotor post that has broken, these are listed as obsolete on the cousins web site, it is a common problem with this movement I dont know if any other supplier would hold this particular part. The ring looks like a tension ring from a watch crystal and is not a part of the movement such as a movement spacer ring as this one is held in place with clamps

Is this post a separate part that gets screwed/attached onto the movement and then you attach the weight or is it attached to the weight itself ?

It's most likely hard to find so only solution would be a donor movement...

Edited by Chopin
Posted

Yes the post is a separate part that is secured with two screws from the under side of the bridge, why not ask for clarification from the seller as to what part is missing or broken if its just one of the screws that holds the rotor post in place it should be easy enough to find a suitable one to use but if it is the post that broken then you will have trouble finding one as you say the way to go would be a donor movement but that may start to make the good price look a little less appealing

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Posted (edited)

Seller doesn't seem knowledgeable. I got another picture from him. Is that the post ? Not the best picture sadly...

20170923_123831.jpg

I think I can see a screw and a missing one... Am I wrong ? Do you have to detach it from the weight to install it onto the movement ? I see no other way...

Edited by Chopin
Posted
1 hour ago, Chopin said:

I have the opportunity to buy a lovely Longines watch but I'd like to know if this is an easy fix. Seller only says that a screw is missing from the oscillating weight and that that's why it's not installed on the movement.

I'm not sure how this one works and how it stays on the movement and I also feel like I see a screw on the weight in the picture. Could someone shed some light on this ? Should the weight have another component that goes into the slot or is just a screw necessary ?

There is a screw on the weight near the movement and I see it in the picture but I assume that's not what we're talking about...

Also, is this even a cal 291 or something else ?

Is the circle in the bag, around the weight, even part of all this ? Could it be some sort of a ring for the movement ? Doesn't seem like it...

20170923_094937.jpg

It's a real pity because looking the movement it is in really good condition apart from the screw or post has been broken. The 291 is obsolete so its up for sale.

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Posted

No the post sits directly in the middle of the movement and is not part or the rotor itself. If the watch is very cheap I would take a punt and factor in the cost of a donor movement if its only slightly cheaper than a  runner walk away.

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Posted
1 minute ago, wls1971 said:

No the post sits directly in the middle of the movement and is not part or the rotor itself. If the watch is very cheap I would take a punt and factor in the cost of a donor movement if its only slightly cheaper than a  runner walk away.

If it is just the post it should be possible to make one,  if you have a lathe that is !!!

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Posted (edited)

So, basically, there should be another part between the movement and the rotor right ? I was hoping that the thing on the underside of the rotor might be it but I guess it's not... Wish I could find a schematic of the movement and see what that part looks like...

No lathe. Not that advanced I'm afraid...

Edited by Chopin
Posted

The axel has broken. The oscillating weight is held onto the axel by a clip, when pushed the weight is free to remove from the axel. The axel is fixed on a plate by two tiny screws underneath. You will need the whole plate.

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Posted

The part it needs is a cal 291 1496 rotor post it is a separate part to the  plate  it is listed on the cousins web site as obsolete

Inked20170923_094937_LI.jpg

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Posted (edited)

Is it this one below ? I keep finding it listed for other calibers so I guess it might be interchangeable... Very pricey sadly.

This part should replace the one marked axle by @wls1971 right ? I'm assuming you remove the top plate, install the new one, put the plate back and then screw it in place with those 2 screws and then the rotor... ?

image.thumb.png.063b2dddc4b7168151160c03f226d33a.png

I wonder if there's a chance that it might not be broken and it's just missing the screws...Only close up shot I have.

20170923_094947.jpg

Edited by Chopin
Posted

no that part is a calibre 505, 1496  and will not fit you need the one specific to the calibre 291

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Posted (edited)

Is the 290 post the same as the 291. I now where you can find one. Send me a PM and i can give you the contact. 

Edited by rogart63
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Posted
25 minutes ago, rogart63 said:

Is the 290 post the same as the 291. I now where you can find one. Send me a PM and i can give you the contact. 

Yes calibre 290 no date calibre 291 addition of date at either 12 o'clock or at 3 o'clock 

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Posted

Thanks guys. I haven't decided if I'll "take a punt".... The price isn't as high as a functional one but not as low as 50$...

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Posted

Even if the automatic winding is not working, it will make a decent enough watch as it can still be hand-wound. From what I recall the 290/291 is derived from the 280 handwinding movement.

Anilv

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