various disassembly issues

Quinn

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I am working to disassemble a Swiss pin set pocket watch, 0s. This watch had a surprise in that the movement cover is glass, quite cool - except that currently a rather rusted movement.

I came across several issues (newbie here):
1. I lost the nail set pin much to my devastation, I did not realize it could be removed and it must have fallen down the sink when I cleaned the case. Can these be replaced?
2. I am having trouble removing the cannon pinion. It's in a recessed location. I do not have the bergeon cannon pinion tool, wondering if that is worthwhile getting and if so my question is are there various sizes and what might work of this 0s; they are quite expensive.
3. The barrel is connected to the bridge and wheel underneath and the arbor does not seem to release easily. I'm not sure on this construction and wanted to make sure it can be released.

Thank you so much for your help.

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darrahg

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I don't know about replacement parts but here are a couple comments about disassembly that might help.
I believe the canon pinion is friction fit. Tap it lightly at the top where the center wheel arbor protrudes and it should free up the canon pinion. Do this carefully.
The disks with two holes are threaded. Get a cheap screw driver of appropriate size and file down the center of the tip so you have the edges protruding. The protruding edges will then go into the holes and you can loosen them. Some use tweezers if they are not on tight. Good luck.
 
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Chris Radek

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The case part you will probably have to make. I can't tell what its shape is exactly, but you will be able to by examining the case and the way it interacts with the movement. It shouldn't be hard (just time consuming) to file one to fit, out of a piece of brass, or silver if appropriate. Leave your piece attached to the larger stock until the very end, so you have a handle to hold it. If the pin is just round (with a shoulder to hold it in the case) a lathe would help, but I think you can still do it by just filing if you don't have one.
 

gmorse

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Hi Quinn,

The centre arbor is probably hollow with a pin running through it. The cannon pinion is a tight fit on this, and the necessary friction to set the hands is provided by the pin rotating in the entre arbor. The washer is to avoid damage to the bridge by the square on the pin.

IMG_0910.JPG IMG_0912.JPG

The hanging barrel is held in place in the bridge by the plate with two holes which is threaded onto the barrel arbor. This picture is of a similar layout, but here the barrel arbor with its integral ratchet wheel screws into the snail inside the barrel. These threads are right-handed as a rule.

IMG_0923.JPG

Put the screws back in the centre wheel bridge before you do anything else.

The hand setting pin should have a flange on the inner end to stop it falling out of the case.

Hope this helps.

Regards,

Graham
 

Skutt50

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1 - Have a look in the air lock under the sink. The missing part may actually be laying there just waiting for you to find it. I have taped a strong magnet on one of the tubes and it is great in catching any ferrous material. It was a long time since I needed it but I have found a screw or two over the years. Once I even lost a jewel in a brass setting. As a last resort I opened the air lock and there it was.

2 - When I punch out the center pin I put the square end in a suitable hole it my staking set. That way I get straight punches and no risk in bending the pin.

3 - I hope you kept track of which screw that goes where. These movements often have different sizes in different places and without tracking, the assembly will be more difficult. Two screws may look identical but will not be interchangeable.(My guess is that it comes from the cottage industri assembly where different parts of the movement was made by different persons.) There are actually some holders with holes for each screw. Old stuff but I use mine all the time.
 
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Quinn

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Thank you guys for all your feedback.

So far no luck on dislodging the canon pinion or the barrel but I will try again tomorrow with a fresh mind. I appreciate all the pictures Graham.

On the nailset pin, I washed two watches right after each other and ironically found 1 of the pins next to the sink. It fits both cases. The head keeps it from falling out to the exterior, but once you remove the movement with a small push it falls out into the case. It was a newbie mistake not to do that and collect it. I don't think I'll be able to fashion one myself but maybe I can find someone to make one for me, since I have the dimensions of the other one.

Skutts, what a great idea to strap a magnet to the pipe, I can do that. I could check the S curve but that little piece is so light it's likely at the bottom of my septic :(. I use that sink a lot.

I do mark where the screws go, I have many containers and tend to keep parts together with their screws given that I'm still learning, especially if screws look similar. I take pictures as remove each piece. One of the cases has 3 bridge screws and one is slightly shorter. So in those circumstances I do keep track especially.
 

gmorse

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Hi Quinn,

So far no luck on dislodging the canon pinion or the barrel but I will try again tomorrow with a fresh mind.
The cannon pinion is often quite tight on that centre pin, not having been dismantled for many years, so a staking set or at least some ingenuity is needed to shift it. If you're going to tap it, make sure that the top plate is properly supported, as Skutt suggests.

There are actually some holders with holes for each screw. Old stuff but I use mine all the time.
I use small 10-compartment fishing tackle boxes to keep associated parts grouped together.

DSCF5480.JPG

Regards,

Graham
 

Skutt50

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I can't find a picture right now and I am not close to my "workshop" but:

The holder I was refering to is a round steel/aluminium piece with the contours of the watch bridges/cocks and several holes drilled. When I remove a screw i fit it in the corresponding hole in the tool. I can even clean the screws while in the tool by submerging it.

I only use it on these movements with several bridges. In my experience even the screws holding a bridge can be different. If not the thread, or length then the head can be slightly different.

This tool is of course no necessity but it is a great help when dealing with this type of movements.
 

Quinn

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The cannon pinion is often quite tight on that centre pin, not having been dismantled for many years, so a staking set or at least some ingenuity is needed to shift it. If you're going to tap it, make sure that the top plate is properly supported, as Skutt suggests.
I was successful with the other two watches carefully prying the pinion up - the problem with this one is its recessed location so I can't get any pry tool underneath (I have that manual remover tool with the two teeth if you will). I will try the poundin method, I'll use a rodico contruction to support it. I am sure though my cheapo hammer will fall apart. I did clean the plate in the hope it would losen gunk. The L&R arrived, by jove what a difference! Parts come out sparkly! (FYI the evaporust also turns everything black but it can be easily removed with a good scrub, leaving a rather dull finish so I'd only do it for watches beyond hope).

I love the fish tackle box! My problem is though that I'd have it open, bump into it, and all the parts will go flying. I use tiny individual boxes so I can close them. Of course that's also because I'm quite slow, so it takes longer, more chance for disaster, distraction and dust. And I am only disassembling at this point for multiple watches at the same time. I do have that compartment thing on order from esslinger (along with the oils and everything else needed for assembly)

The holder I was refering to is a round steel/aluminium piece with the contours of the watch bridges/cocks and several holes drilled. When I remove a screw i fit it in the corresponding hole in the tool. I can even clean the screws while in the tool by submerging it.
Now this I have to see! Another tool to buy? Oh no!

A pic of my little boxes and also the nailset pin that I found, which does fit ironically both the watches I worked on - and one of which I lost (checked the pipes, no dice). It's 4.71mm long, 1.40 wide, with the head being 1.69 wide. The head is to depress the mechanism, and the other narrow end is stamped with a pattern and is depressed by the nail. But I'm sure you knew all that ;).

Thanks for your help everyone.

2021-03-03 07.25.11.jpg PICA0000.jpg PICA0001.jpg PICA0002.jpg
 

gmorse

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Hi Quinn,

I'll use a rodico contruction to support it.
It will need to be more solid than that; the stuff is like putty and will deform very easily! A solid metal block that will support the plate but allow the end of the pin to pass freely through a suitable hole will be better; this is effectively what a staking set is after all.

Regards,

Graham
 

Jerry Treiman

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3 - I hope you kept track of which screw that goes where. These movements often have different sizes in different places and without tracking, the assembly will be more difficult. Two screws may look identical but will not be interchangeable.(My guess is that it comes from the cottage industri assembly where different parts of the movement was made by different persons.) There are actually some holders with holes for each screw. Old stuff but I use mine all the time.
The holder I was refering to is a round steel/aluminium piece with the contours of the watch bridges/cocks and several holes drilled. When I remove a screw i fit it in the corresponding hole in the tool.
I think this is what Skutt50 is referring to --
screw holder.jpg
It is not really needed for most American movements where there was a lot more uniformity.
 

Skutt50

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Thanks... Thats it.

This is not intended for US movements but rather old Swiss movements with the typical bridge design... (Le Paine??)
 

Quinn

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That is a fantastic tool, thanks for sharing that! Mmm. I'll have to keep an eye out for one of those. I'm quite partial to some of the French silver pocket watch cases, all of which seem to come with the fiddly Swiss movements.

OK so no rodico, I didn't think I'd be hitting it that hard, yikes. Should I just get the cannon pinion remover tool or would that not work.

On the nailset pin, I'm a bit in the boonies in the desert ... but if someone here wants to make me one I'd reward handsomely :). I might see if I can buy a junker to harvest a pin off of but they do vary in size, one of my other swiss' has a huge (relatively) clunker.

Thanks again everyone for your help!!
 

Skutt50

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Should I just get the cannon pinion remover tool or would that not work.
You need to support the bridge over a small hole. If nothing else a piece of hard wood with a 2-3 mm drilled hole would do. Then just hit the other end of the pin untill it is flush with the top of the canon pinion. After that you should be able to just pull it out.....

The nailset pin would probably vary from one case to another. Could you possibly fit a screw in a hand drill and cut it down with a file? (A hand drill was my first "lathe" before I started to learn more about watchaking......lol.)
 
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Quinn

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Ah wood and a drill, now you're talking! That I can do. I suppose though using my framing hammer is out of the question :).

This size pin actually works for the case I lost it from, go figure. Filing a screw is not a bad idea either.

Thanks!!
 

Skutt50

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I suppose though using my framing hammer is out of the question
Depends on how hard you hit.....But I would suggest a much smaller hammer.

Before you hit it make sure the back of the pin is above the hole in the wood.
 

gmorse

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Hi Quinn,

Depends on how hard you hit.....But I would suggest a much smaller hammer.
Yes indeed, even a 4 oz hammer is on the large side, but whatever you use, just gentle taps until you see the pin start to move! You can pick up watchmaker's brass-headed hammers fairly cheaply.

Regards,

Graham
 
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Bohemian Bill

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Hi Quinn,



Yes indeed, even a 4 oz hammer is on the large side, but whatever you use, just gentle taps until you see the pin start to move! You can pick up watchmaker's brass-headed hammers fairly cheaply.

Regards,

Graham
Hi All..I made a small/tiny hammer from a 1/2 inch dia x 2 inch long copper bolt that I pick up/found somewhere, I turned all the threads off and drilled for handle. You could make one out of a brass bolt and drill the bolt for a 1/4 inch steel handle shaft and put some electrical rubber heat shrink for a grip. It fits nicely in my staking set for staking staffs. It works great with the large head on one end. My whole hammer weighs only about 2.5 oz
 
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Quinn

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Thank you all for the advice - I was off for a bit, have not tried to remove the cannon pinion yet. I have a little nylon hammer that I may try first that came with my cheapo watchmaker's kit. If that doesn't work I'll have to wait for the esslinger order.

I did disassemble another Swiss watch today and the cannon pinion came off so easily!

If it's OK I have a few questions about this new pocket watch. It's a Swiss Galonne case, 0,08 with a grouse, nail pin set (managed not to lose it this time!). The barrel was caked in a light oil, as if someone had just squirted it in. The main spring was set. While cleaning parts of this movement the L&R 566 turned blue. Is this an indication it needs to be changed? Is it a reaction to something?

Also I wondered if that solution is safe for the silver/gold case. I have not used it. If not, do I need to get the L&R jewelry solution?

In measuring springs, Graham, you mentioned the micrometer, which I have on order. I used my digital calipers, they seem pretty precise actually - but I noticed to measure strength I got 0.18 - 0.20 depending on how hard I pushed the calipers closed. Maybe this is why a micrometer is better?

The end of the spring befuddled me a bit, it seemed cut? Not sure what I'm looking at, any input appreciated.

The main plate jewel for the pallet fork appears shot to me. It looks OK from the other side, but it seems hollowed out where to pivot goes. The pivot on the fork is in good shape.

Thanks for all your help.

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Skutt50

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I got 0.18 - 0.20 depending on how hard I pushed the calipers closed
I assume you have a digital caliper. How har do you push when you zero it? Use the same strength when you measure.

The end of the spring befuddled me a bit, it seemed cut?
It looks like the end of the spring (that catche the barrel hook) has been broken off. The watch should still wind but before fully wound the mainspring will slip and the watch will not run for very long.

The main plate jewel for the pallet fork appears shot to me.
One can't tell before it has been cleaned. It may look suspisious now, but a thorough cleaning may reveal a perfectly good jewel..........
 

gmorse

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Hi Quinn,

While cleaning parts of this movement the L&R 566 turned blue. Is this an indication it needs to be changed? Is it a reaction to something?
It should be changed, the colour is probably the result of the old oil and dirt, plus a contribution from the brass. When working on a very dirty movement, it's a good idea to do a pre-wash in naphtha to remove the worst soiling and save your expensive L&R solutions.

'Galonne' is gold-plated silver, and if the gold is thin or appears worn through in places, I should just clean it in dish soap and warm water to start with which is probably enough.

The point about micrometers, apart from their inherently greater accuracy, is that the thimble has a ratchet mechanism, (the small knurled knob on the end), which helps in achieving repeatable readings, although for very small parts you still need to develop the 'feel'.

The jewel is indeed filthy, but it should have a depression in the centre, which is the oil sink; as Skutt says, have a close look after it's clean.

Regards,

Graham
 

Quinn

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Thank you my learned friends :)

I assume you have a digital caliper. How har do you push when you zero it? Use the same strength when you measure.
Yes I have digital calipers, decent quality. It's 0.20 just pushing the caliper on the knob and then releasing the knob. It's 0.18 if I then push the knob a little further (not pressing super hard). I'm unversed in the strength and what it would mean to go higher or lower.

It looks like the end of the spring (that catche the barrel hook) has been broken off. The watch should still wind but before fully wound the mainspring will slip and the watch will not run for very long.
This was precisely the note from the seller, mainspring slips. So that opens up another can of worms, is it possible the spring broke and the remaining piece was put back in. That leaves me to want to calculate the main spring size - barrel is 16.91 and the height appears 3.34 with bottom which is 1.00 so 2.24? I'll have to check how you measure the height. This spring is 2.31 H, 0.19 S, 49.5 L.

On the jewel, here is the cleaned pic, lesson learned, I added the before because it seemed a better pic ... Let me know your thoughts. It's possible it's still not clean, there was so much oil around the barrel.
It should be changed, the colour is probably the result of the old oil and dirt, plus a contribution from the brass. When working on a very dirty movement, it's a good idea to do a pre-wash in naphtha to remove the worst soiling and save your expensive L&R solutions.
Thank you Graham, that is a very useful tip. On amazon I see Kleanstrip VM&P Naphtha, would that do? I had a feeling it was the brass (and the dirt) - the baskets I have are brass too and I noticed they're changing color. The other movements I had so far were largely nickel.

Thank you for the note on the cleaning of Galonne, I had read it was an inferior gold plating. I tried to find the hallmarks with little luck, I see the grouse, crescent and crown, but I could not find the JW or the Y. I have put cases in dish soap and water in the US before but I worry the metal plate inside the case to push the front off might rust. The case is silver with a seemingly rose gold edge, it's quite beautiful (I'm partial to silver). The pic has too much reflection I'll have to try one in daylight. And do you see my latest acquisition in the background? The vintage K&D...

That is a good explanation on the micrometer, thank you. I will wait to order the main springs until it comes in and remeasure them.

Oil sink!! That I did not know, fascinating. Thank you both for your time in helping me, much appreciated.

jewel-palletfork-bottom-clean.jpg 2021-03-07 06.23.18.jpg 2021-03-06 07.16.30.jpg
 
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gmorse

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Hi Quinn,

I'll have to check how you measure the height.
If you mean the internal height of the barrel, measure the external height and the thicknesses of the barrel base and lid and subtract those two from the external height. You'll find it easier to measure the barrel base with a micrometer, although a method if you can't access the base properly, is to use a small ball bearing and measure that by itself and then inside the barrel. The base thickness is then the difference. Make sure you measure the thicknesses where the spring actually sits and not the thicker bosses around the centre holes.

I have put cases in dish soap and water in the US before but I worry the metal plate inside the case to push the front off might rust
The steel springs which lift the front lid, (the fly spring), and lock it, (the locking head), will rust if left wet, but the same applies to these as for any other steel parts; if necessary dunk them in alcohol and blow dry. The alcohol, (ethanol or isopropyl are probably easiest to obtain), will absorb the water.

On amazon I see Kleanstrip VM&P Naphtha, would that do?
I suspect that this stuff is more akin to mineral spirits, meant for use as a paint thinner. I was intending Ronsonol or Zippo lighter fuels, which leave little or no residue, but for this purpose that doesn't matter since you'll be putting them through the ultrasonic afterwards. I don't recommend using any of these in the ultrasonic, however, just use the L&R in that.

Some records for Swiss and French case makers do exist, but they're nowhere near as comprehensive as the UK hallmarking records.

Regards,

Graham
 

Skutt50

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If you push the caliper to its closing position, does it show 0.00 when you let go of the knob?
What if you now put some preassure on it?

I would expect the pallet fork jewel to have a hole for the pivot. This looks more like a scratched end stone. Are you sure it is clean? Did you try some pegwood to clean the hole? (A sharpened toothpick will do.)
 

gmorse

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Hi Quinn,

I think your picture of the lever pivot jewel shows that there's still some oil or other liquid on it, so I do agree with Skutt that it's still dirty but I don't believe that this is an endstone; it's rubbed into the plate.

The case in your latest picture doesn't need anything more doing to it, it's come up quite well.

Regards,

Graham
 

Quinn

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Thank you guys again for your replies.

Graham - Thank you on the barrel measuring info. The calipers were able to measure the base - I forgot about the lid. What I do see is that already without the lid subtracted the barrel height seems smaller (3.34-1.00=2.24) than the height of the current spring 2.31. It did seem in there quite tight - or an indication my measurements need checking.

fly spring! Excellent, another term. Yes, I do dip in alcohol profusely now.

On the naphtha, I will search for zippo fluid I'm sure it's gettable.

On the hallmarks, there are a few specialized forums, I might try them, it's always fun to know.

Skutts: I do zero out the calipers when closed and so they read 0.00 when I close them again, but it's a good thing to double check, thank you.

I am a dufus. The jewel is on the dial side of the main plate. To the best of my recollection the other side where the pivot sites looks fine (not at my microscope right now but will check). I will try the toothpick, the pegwood will come with the large esslinger order.

I wanted to ask, before I pull the trigger on that order if I have all the oils I need. I got:
9010
941
8200
9104
8203

2021-03-06 13.55.02-2.jpg
 

gmorse

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Hi Quinn,

I wanted to ask, before I pull the trigger on that order if I have all the oils I need. I got:
9010 Yes, might add 9020 or 9101 (Synt-HP 500) for trains in larger movements
941 Yes, but I think 9415 is better, since it stays put
8200 Yes, good basic grease, or 8300 if you need something thicker
9104 Yes, aka Synt-HP 1300, good high-pressure oil for barrel and centre arbors
8203 Not sure why you'd need this if you have 8300
I'd add KT22 (Bergeon 2588) for keyless work, it's water-resistant and won't dry out.

What I do see is that already without the lid subtracted the barrel height seems smaller (3.34-1.00=2.24) than the height of the current spring 2.31. It did seem in there quite tight - or an indication my measurements need checking.
1mm seems rather thick for a barrel lid; are you measuring the centre boss or the part where the spring sits? If the spring is too high the lid won't close properly. Are you measuring the barrel base with the tail-end of your vernier calipers?

Regards,

Graham
 
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Quinn

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Thanks Graham for all the helpful notes on the oils, and good catch on the 8203. I'll just get 8200 and 8300 and fix the other ones, and add KT22. I'm glad I asked!

1mm is for the barrel bottom - yes the lid is much thinner, did not measure yet. I did measure the barrel bottom with the tail end of the venier calipers (it's about all that fits). So barrel total height 3.24 - barrel bottom 1mm = 2.24; then I still have to subtract the lid. I will try the ball bearing method and remeasure the spring width. Why has some engineer not made a measuring tool for the barrel :).

Another question, how do I know which tail end to buy for the spring? Is there any indication inside the barrel? Thank you!
 

Skutt50

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If you take a close up photo of the barrel interior where the "hook" or similar is visable we can tell you about the spring end.

From the remains of the old spring it looks like a spring with a "Normal Bridle" i.e. a flap that catches a hook. It can be either a small flap/piece that is rivited on the end of the spring or a fold of the spring. Another version is where a small fold on the mainspring is used to hold a small flap often made of a few mm mainspring that was broken off.
 

Quinn

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Thanks Skutt - to me from the microscope pictures it looks like there is no flap or rivit, it just stops. (I posted those earlier, not sure if you saw them).

Here's a pic of the barrel, I hope that helps. The giant scratches were not me.

Graham, I measured the barrel lid, it's 0.55 on the outside; there is a raised circle in the middle that would make it 0.92. I did find in remeasuring the barrel I'm getting a lot of variance from 3.31 to 3.39 even depending on how I hold the tail end of the calipers. I noticed this with the spring as well. So better to remeasure once the micrometer arrives.

thanks again for all your help!

2021-03-07 13.19.32.jpg
 
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gmorse

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Hi Quinn,

With all measuring instruments, the accuracy depends to a greater or lesser extent on the skill of the operator, irrespective of their inherent quality of construction. Vernier calipers can give varying readings if the jaws aren't quite flat on the surface being measured, because they have a finite thickness, and this is especially true when using the 'tail end' of the instrument to measure depths. Micrometers can also vary, even though the ratchet on the thimble is intended to reduce the variability of hand pressure. They're also susceptible to dust on the jaws, especially on the types which measure to 0.001 mm.

The jaws of most general purpose micrometers are around 0.25" (6.35mm), in diameter, which may be too big to fit in the barrel, hence my suggestion of a ball bearing.

Regards,

Graham
 

Quinn

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Thank you Skutt that's very helpful. I will do some reading on sizing main springs which is a bit of a pill. And I have a book on watch repair I'm working through. Disassembly and cleaning is one thing; the real work is putting it together right, which takes a "bit" more education. Thank you and Graham so much for helping me through this process.
 

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