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Replacing 'case mount pin'?

ErichKeane
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So backstory: I have an Omega Bumper 2635-1 that has a 2810 RA PC (PRE 340!) in it that sadly has seen better days. The canon pinion and hour wheel were rusted, so someone tried to force time-set at one point, and snapped the minute wheel pin off the movement.

SO, I picked up a 343 in... mediocre condition that I'm going to try to make a good watch out of (plus some ebay ordered parts... sigh), currently disassembled and in the cleaner 馃榾

However, one thing I noticed is that the 343 is missing the 'pin' that is used to hold it into the case. This is one of those single-case-clamp movements, where hte other side just has a pin.

The 340 its there but rusty, the 343 is missing. It SEEMS like this is something I should be able to just loctite a piece of stock into place? Is there anything special about it that I need to know?
 
sheepdoll
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I am in the same situation. Ran some bumpers through Alum to remove broken screws.

I have a lathe and some small wire. Mostly I need motivation.

the 353 watch movement I got this week still has a good pin. So I can see what it should look like. Sometimes I see part of the pin ground away to clear the rotor.
 
ErichKeane
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I spent some time looking at this/trying to measure it. The hole itself is somewhere around 0.002"? So 0.50mm or so? Is there anywhere I can just buy a variety of rods that small? Perhaps some that will be touched by a file if need-be?

EDIT: NVM: It isn't something I can do with just stock, the hole in the movement is really tiny, but the pin itself expands to ~10x that. after getting out of the movement. Looks like i'm going to have to figure out how to get my 16" lathe to make it 馃榿
Edited:
 
Archer
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The part you need is called a plate fastener - 330.1022

It is the same part used across all the 330, 340, and 350 calibers. It is long discontinued as a part, but you might be able to find one using the part number on the open market.
 
sheepdoll
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Large lathes with good turnout make great small parts.

I sorted through my 33x/34x/35x stuff. Looks like one of the plates replaced the pin with a tiny screw, Like a small dial screw or hairspring set screw.

Got out the 2577 that needs this pin. I got the clamps, case tube and crown ages ago. Those parts wound up with the other blob of parts. Do have a number of lathes, as noted mostly lack motivation. Motivation for sharpening the tool. They always come out convex when I want them concave or hollow ground with a negative rake.

The new plate has a much better pin. Could try seeing if I can pull it out to swap in. Too bad I do not have a good spare balance (hairspring.)

A 2635-7 mid case is also on the wishlist.
 
ErichKeane
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Archer Archer
The part you need is called a plate fastener - 330.1022

It is the same part used across all the 330, 340, and 350 calibers. It is long discontinued as a part, but you might be able to find one using the part number on the open market.
Oh wow, thanks! I didn't even THINK this would be a a purchase-able part! Sadly none on ebay, but I can do some research!

sheepdoll sheepdoll
Large lathes with good turnout make great small parts.

I sorted through my 33x/34x/35x stuff. Looks like one of the plates replaced the pin with a tiny screw, Like a small dial screw or hairspring set screw.

Got out the 2577 that needs this pin. I got the clamps, case tube and crown ages ago. Those parts wound up with the other blob of parts. Do have a number of lathes, as noted mostly lack motivation. Motivation for sharpening the tool. They always come out convex when I want them concave or hollow ground with a negative rake.

The new plate has a much better pin. Could try seeing if I can pull it out to swap in. Too bad I do not have a good spare balance (hairspring.)

A 2635-7 mid case is also on the wishlist.

Making small parts means really really sharp tools and really really gentle cuts, and doesn't give you nearly as much warning when running 15 hp as a smaller lathe 馃榾 Also, a massive spinning chuck makes it that much scarier if you hand-cut.

Trying to find a junk-screw that might fit isn't a bad idea. I don't have any taps for these sizes, but maybe I could make something work.

I'll have to ruminate on this a bit, it would be great to find a replacement, but it would be a shame to have to do that for something this simple.
 
ErichKeane
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Actually... I HAVE one of these pins. Not in great shape, but in the other busted main plate. Does anyone have a clue how it is held in? It's a bit small to punch out, so I would love ideas how to remove it .
 
ErichKeane
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JimInOz JimInOz
You should be able to get a bundle of pivot wires from your local watch house.

https://www.esslinger.com/staff-and...8q0xqcl7zWGsBzom9_mWL6YdtbnlJMteoz6SR-jc7xqDj

They call it wire, but it's actually straight rods of many diameters

Many sizes you may never use, but they do come in handy.

Pivot wire.webp
I might just, that DOES sound like a useful set! Unfortunately this isn't just 'straight rod' as I'd hoped, it is a stepped size down to something ridiculous 馃榾 I was hoping to not have to learn watchmaking lathe work yet....
 
Archer
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ErichKeane ErichKeane
Actually... I HAVE one of these pins. Not in great shape, but in the other busted main plate. Does anyone have a clue how it is held in? It's a bit small to punch out, so I would love ideas how to remove it .
I believe it is just a press fit.
 
ErichKeane
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Archer Archer
I believe it is just a press fit.
I was afraid of that 馃榿 The end is something like 0.050mm as best I can tell, so something that CAN press that out is gonna be tough...

I'll give it a try when I figure out how to be brave enough. Thanks!
 
ErichKeane
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UPDATE! I snapped the end off of one of my Bergeon oilers that seemed to be made out of 'spring' steel (so it doesn't bend, it holds its shape).

I used some sandpaper to shrink it a little, but it was enough to get through the hole in the plate (confirmed on the new plate). It didn't take more than about 20 seconds to make this happen.

I then just used it as a punch and one light tap with a hammer and it popped out! I even lucked into it not joining the swiss space program and staying within view!

So I think I saved i! I might try some loctite purple to hold it into place on the plate when I re-assemble just to make sure it stays in place (since it is probably a 'looser' fit than factory now that I punched it out). BUT I think I'm unblocked on this, at least until I need some of the parts that haven't shown up yet.
 
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