Some Longines Repair Questions

[Skutt50]

That said, I don't know why else they would put the slot on there unless that was the intention.

I use the slot for fine tuning the direction of the hairspring meaning turning the hairspring so the hairspring moves correctly between the regulator pins.....

 

[John Hinkey]

I use the slot for fine tuning the direction of the hairspring meaning turning the hairspring so the hairspring moves correctly between the regulator pins.....

Well there you go - someone smarter than us knows the likely reason for this slot!

 

[MrRoundel]

I'm assuming they put a slit in there to help push the pin in using a screwdriver?

That does makes sense. Better thinking.

 

[MrRoundel]

Well there you go - someone smarter than us knows the likely reason for this slot!

Well, at least in my case, searching for someone smarter may have been the world's briefest search.

 

[gmorse]

Hi John,

I did mention the reason for that slot earlier. With the correctly fitting screwdriver, you don't need to press down, it's a matter of developing the delicate feel.

Pliers with serrated jaws have no place on a watchmaking bench!

Regards,

Graham

 

[John Hinkey]

Hi John,

I did mention the reason for that slot earlier. With the correctly fitting screwdriver, you don't need to press down, it's a matter of developing the delicate feel.

Pliers with serrated jaws have no place on a watchmaking bench!

Regards,

Graham

Aw now, these are 1mm wide micro needle nose pliers and they certainly have come in handy trying to grip tiny pins and whatnot that tweezers won't even begin to grab onto. Rarely used, but useful when they are the last resort.

 

[gmorse]

Hi John,

I'll give you 'last resort' then, seeing how tiny they are!

Regards,

Graham

 

[roughbarked]

Oh, and my vote is for less caffeine, not more. Kalle from chronoglide (youtube) recommends being completely relaxed, "zen", before doing any work on hairsprings. While this tip applied to straightening distorted hairsprings, it might apply to relative newbies removing and installing them as well. I know that I have to walk away sometimes and get "re-centered" when dealing with them. Cheers.

More caffeine = more handshake.

The pin is pushed out rather than pulled.
I cut the end off one side of the tweezers and bend the other side tip at right angle. Do it so the bent end passes closely to the cut end. This makes a useful tool for pushing hairspring stud pins out.

 

[John Hinkey]

More caffeine, more handshake.

Oh, for those fully caffeinated on a regular basis I'm not so sure

 

[roughbarked]

One may develop a stronger tolerance over many years.

 

[John Hinkey]

Ok, back to work. Strange things I see in the main plate balance cap jewel:

so there appears to be black specks INSIDE the jewel.
This has been cleaned in Naptha & alcohol and rubbed with pegwood.
The flat side of the jewel has a divot in it, but not where the end of the pivot touches, which looks pretty good.
I'm pretty certain all the built up old oils have been removed and what you are looking at in the last image is the flat face of the jewel.
So this looks OK to me (meaning functional) despite the surface flaws. The jewel in the main plate looks good (i.e, not cracked).

Thoughts?

- John

 

[svenedin]

If it’s actually inside the jewel then possibly it’s a natural jewel and these are inclusions of some sort.

 

[gmorse]

Hi John,

so there appears to be black specks INSIDE the jewel.
This has been cleaned in Naptha & alcohol and rubbed with pegwood.
The flat side of the jewel has a divot in it, but not where the end of the pivot touches, which looks pretty good.
I'm pretty certain all the built up old oils have been removed and what you are looking at in the last image is the flat face of the jewel.

Stephen is quite right, these are inclusions. Many older jewels were effectively rejects, not cosmetically good enough for jewellery, but perfectly adequate for watch bearings. Before the widespread availability of synthetic jewels at the beginning of the 20th century, these would have been low grade natural stones, and not necessarily all corundum, (ruby and sapphire, not quite as hard as diamond). Garnet, rock crystal (quartz), beryl, and many other minerals were used, especially in the lower grades.

Regards,

Graham

 

[John Hinkey]

One last sanity check before I attempt to open up the mainspring barrel:

I assume I just put this on my anvil surface and push downward around the periphery of the barrel so that the arbor pops out along with the barrel cover?
Thanks -

John

 

[roughbarked]

One last sanity check before I attempt to open up the mainspring barrel:
View attachment 704893
View attachment 704894
I assume I just put this on my anvil surface and push downward around the periphery of the barrel so that the arbor pops out along with the barrel cover?
Thanks -

John

Yes. But keep a finger loosely holding the cap so that it doesn't fly off with the mainspring too. It may help to remove the ratchet wheel first.

 

[John Hinkey]

Yes. But keep a finger loosely holding the cap so that it doesn't fly off with the mainspring too. It may help to remove the ratchet wheel first.

I want to remove the ratchet wheel, but I don't know how it's attached to the arbor - seems it is one piece - that can't be right - right?
I'll see if I can get it to come off nicely w/o damaging the cover.
I cannot find any pictures or video of taking apart a barrel like this one with the integrated ratchet wheel.

- John

 

[roughbarked]

Normally, one doesn

I want to remove the ratchet wheel, but I don't know how it's attached to the arbor - seems it is one piece - that can't be right - right?
I'll see if I can get it to come off nicely w/o damaging the cover.
I cannot find any pictures or video of taking apart a barrel like this one with the integrated ratchet wheel.

- John

Normally one doesn't wish to remove the arbor with the lid because this can cause the whole mainspring to come adrift, which it does in a big way when released.
The ratchet wheel should in most instances come off.

 

[John Hinkey]

OK, figured out that the ratchet wheel was just held on by a friction fit square shoulder/socket and some light prying around underneath the wheel loosened it up and it fell off. Barrel cover off and spring out. No surprise that the spring is set and the barrel has lots of gummy stuff inside:

time to take some spring and barrel measurements and find a new mainspring with a T end.

 

[John Hinkey]

Also took some back-lit images and close-up images of all the main plate and bridge jewels and confirmed that only one is cracked. These are post initial naptha bath and pegging:

one of these jewels on the main bridge is clearly cracked:

main plate jewels need some more cleaning, but look OK:

this last one above is the balance jewel in the main plate. It has some marks across it, but there are no cracks.

I now need to do another cleaning with the L&R111 that's coming at the end of the week.

Now on to the balance spring removal . . . ugh.

Thanks for all your help and encouragement!

- John

 

[gmorse]

Hi John,

Now on to the balance spring removal . . . ugh.

Take it gently, the studs mostly do come out quite easily after some initial reluctance. When you lift out the balance cock complete with the balance, be careful that the wheel doesn't get caught under the centre wheel and don't worry about the wheel hanging from its balance spring, just ease it out and lay it down on the bench. You can then carefully turn it over and attend to the the regulator boot if there is one, before popping the stud out.

Congratulations on your excellent pictures by the way, I wish more enquirers here took as much trouble!

Regards,

Graham

 

[John Hinkey]

Hi John,


Take it gently, the studs mostly do come out quite easily after some initial reluctance. When you lift out the balance cock complete with the balance, be careful that the wheel doesn't get caught under the centre wheel and don't worry about the wheel hanging from its balance spring, just ease it out and lay it down on the bench. You can then carefully turn it over and attend to the the regulator boot if there is one, before popping the stud out.

Congratulations on your excellent pictures by the way, I wish more enquirers here took as much trouble!

Regards,

Graham

Thanks Graham, I think I'm well past the "be careful taking the balance out" stage of things :

thanks for the complement on the pictures. I'm an engineer and amateur photographer that has done a fair amount of work taking pics of small engineering components. I have the luxury of having some nice camera gear and video/computer equipment which helps a lot. I'm also quite near-sighted which is also a plus!

 

[John Hinkey]

Here's the mainspring measurements that I'll use to figure out a replacement:
Width: 2.61mm +/-0.01mm
Thick: 0.20-0.21mm +/-0.01mm
Barrel ID: 15.29mm +/-0.01mm
Barrel Depth: 2.70mm +/-~0.05mm (this takes into account the cover thickness, so a 2.6mm spring is as wide as it will take).
Arbor Diameter: 5.10mm

I'll clean up the parts and re-measure, but those are the basics. I'll propose some springs based on the well know spring calculate web site that I used for my Tavannes spring selection.

Edit: Some calculations from the on-line mainspring calculators of Watch Mainsprings
Length From Thickness Calculator:
0.20mm thickness -> 408mm length -> 6 turns
0.21mm thickness -> 389mm length -> 5.7 turns
which indicates my spring is too thick as the turns are less than 6.5 or so

Required Turns Calculator:
spring thickness = 0.185, length = 441mm
which indicates my spring thickness should be 0.185mm to get 6.5 turns

Length From Weight Calculator:
carbon steel spring = 485mm

So this calculator is suggesting my current spring is too thick and suggests a 0.18 to 0.19mm thick 441mm to 485mm length.

Time to start searching CousinsUK and Ofrei to find something with a T-end.

Should I stick with a 0.21mm thick spring with fewer turns/shorter length or go for 0.18-0.19mm thick and more turns/length?
I know that the spring torque/force is strongly a function of thickness and to err on that side if possible.

Thoughts?

 

[John Hinkey]

Can't find anything on Ofrei with a T-end that's even close, but CousinsUK has this:

2.60 x .195 x 540 x 16.5 T- End
which is long and I'd have to hand wind it since the 16.5 diameter is too big to just push in directly.

I could go 2.50mm width:
2.50 x .19 x 500 x 15.5 T- End
but that gives me a weaker, shorter spring that the T-end might not fit and I still need to hand wind it.

Any other mainspring places besides CousinsUK or Ofrei to buy a replacement spring from?

- John

 

[gmorse]

Hi John,

I haven't found anyone other than Cousins in the UK selling a reasonable range of springs, although Gleave & Co. carry a few, they're mostly in the smaller sizes for wrist watches. Have you tried Daves watch parts?

Regards,

Graham

 

[John Hinkey]

Hi John,

I haven't found anyone other than Cousins in the UK selling a reasonable range of springs, although Gleave & Co. carry a few, they're mostly in the smaller sizes for wrist watches. Have you tried Daves watch parts?

Regards,

Graham

Gleave & Co. has nothing in this range. I've sent an email into Dave to see if he has anything.
This mainspring might not be original. I need to open up one of the other movements that I have to see what spring is in there.

 

[roughbarked]

A T end mainspring should have a slot for the T in the barrel as well as the lid.

 

[John Hinkey]

A T end mainspring should have a slot for the T in the barrel as well as the lid.

Yes, there is a hole (not a slot) in both halves of the barrel:

 

[svenedin]

You just need a mainspring with an ordinary bridle. The bridle will catch the hook on the barrel. The other end has a hole which engages with the pin on the arbor. The bridle looks like a short extra piece of spring at one end -see your spring.

 

[John Hinkey]

You just need a mainspring with an ordinary bridle. The bridle will catch the hook on the barrel. The other end has a hole which engages with the pin on the arbor. The bridle looks like a short extra piece of spring at one end -see your spring.

Incorrect
There is no hook in the barrel for anything to catch on - it is completely smooth inside. This requires a "T" or a "Longines T" end to the mainspring:

 

[svenedin]

Fair enough I couldn’t really see from the pictures of the barrel, cap and spring.

 

[John Hinkey]

Fair enough I couldn’t really see from the pictures of the barrel, cap and spring.

Sorry for the abruptness - didn't quite have my morning coffee yet

 

[svenedin]

Sorry for the abruptness - didn't quite have my morning coffee yet

For me it’s early evening but I haven’t had a sundowner yet!

 

[John Hinkey]

Here's a close-up of the end of the spring that I pulled out:

The end is riveted on and doesn't look too home-made. Maybe they came from the factory like this back in the day.

- J

 

[John Hinkey]

Can't find anything on Ofrei with a T-end that's even close, but CousinsUK has this:

2.60 x .195 x 540 x 16.5 T- End
which is long and I'd have to hand wind it since the 16.5 diameter is too big to just push in directly.

I could go 2.50mm width:
2.50 x .19 x 500 x 15.5 T- End
but that gives me a weaker, shorter spring that the T-end might not fit and I still need to hand wind it.

Any other mainspring places besides CousinsUK or Ofrei to buy a replacement spring from?

- John

So, should I just order the top one since it's the closest in width, thickness to what I pulled out (though significantly longer) and just have to hand wind it in?
Been thinking of making my own winder specifically for this barrel internal diameter and mainspring end type.

 

[John Hinkey]

Here's a close-up of the end of the spring that I pulled out:
View attachment 705163
The end is riveted on and doesn't look too home-made. Maybe they came from the factory like this back in the day.

- J

I opened up a nearly identical donor movement to look at the mainspring and it appears identical to this one. So this is likely the original that came with the movement over 100 years ago.

 

[John Hinkey]

Went ahead and ordered the 2.60 x .195 x 540 x 16.5 T- End from CousinsUK.

Dave at Dave's Watch Parts had something similar, but I placed the Cousins order just before Dave got back to me.

 

[John Hinkey]

Just got delivery of the L&R 111 cleaner - OMG! This stuff is magic for brass parts. 3 minutes in a small jar with some manual swirling and parts come out way squeaky clean. A bit nasty if you get a sniff, but it does seem to work magic. Does need a rinse (I used alcohol or naptha) to get any residual off, but that's a small price to pay. Parts way cleaner and certainly hugely brighter with L&R111 vs. naptha or alcohol.
The magic of chemistry!

 

[svenedin]

Just got delivery of the L&R 111 cleaner - OMG! This stuff is magic for brass parts. 3 minutes in a small jar with some manual swirling and parts come out way squeaky clean. A bit nasty if you get a sniff, but it does seem to work magic. Does need a rinse (I used alcohol or naptha) to get any residual off, but that's a small price to pay. Parts way cleaner and certainly hugely brighter with L&R111 vs. naptha or alcohol.
The magic of chemistry!

I use something similar and then the manufacturer’s rinse in the ultrasonic. Yes it does absolute wonders to get the dirt and surface oxidation off. The offensive bit is ammonia so do use it where you have good ventilation. I reuse the cleaning solution until it’s fairly grotty and use the dirty solution for cleaning the watch case which is usually filthy and it isn’t critical to get it spotless like the movement.

 

[John Hinkey]

I use something similar and then the manufacturer’s rinse in the ultrasonic. Yes it does absolute wonders to get the dirt and surface oxidation off. The offensive bit is ammonia so do use it where you have good ventilation. I reuse the cleaning solution until it’s fairly grotty and use the dirty solution for cleaning the watch case which is usually filthy and it isn’t critical to get it spotless like the movement.

Unfortunately no ultrasonic for me, just manual cleaning in naptha, then rinse in L&R it seems with a done of IPA for parts that don't have pallet or roller table jewels.
I've been waiting for the L&R to clean my Tavannes watch that is still heavily stained after Naptha and IPA cleaning.

Now onto the cleaning of the balance spring and jewel . . .

 

[svenedin]

Unfortunately no ultrasonic for me, just manual cleaning in naptha, then rinse in L&R it seems with a done of IPA for parts that don't have pallet or roller table jewels.
I've been waiting for the L&R to clean my Tavannes watch that is still heavily stained after Naptha and IPA cleaning.

Now onto the cleaning of the balance spring and jewel . . .

Do you have Essence Of Renata for that? Just a quick dip and a gentle swish and out. It's very volatile so keep in a small jar with a tight fitting lid. I use one of the individual serving glass jam jars from some posh hotel or other.

 

[John Hinkey]

Do you have Essence Of Renata for that? Just a quick dip and a gentle swish and out. It's very volatile so keep in a small jar with a tight fitting lid. I use one of the individual serving glass jam jars from some posh hotel or other.

Unfortunately no, I have not been able to find any in the USA, though I just see that CousinsUK sells it in 250mL sizes.
I still need to separate the balance spring from the cock so I can clean the jewels on the balance cock.

EDIT - I see that CousinsUK will not ship this stuff to the US. Where in the US can you get this?

 

[John Hinkey]

Well, I manned up and removed the balance spring from the balance cock. Sorry Graham I used my micro-needle nose pliers to grab onto the hairspring stud and gently pivoted it back and forth until it gently came out. No special setup needed to push it out from above.

Now I've cleaned out the balance cock jewels and just need to clean the balance spring, which is pretty darned clean as it is.
Clearly some of these small screws have been unscrewed for servicing before - that or the factory did a poor job installing them. Who knows.
Pics below.

dirty balance cock jewel

jewel inclusions visible through the top:

all apart:

after a couple of LR111 and Naptha cleaning cycles:

this jewel might have a slight chip in the pivot hole, but it's not too bad. I'll see what the donor movement jewel looks like.
May just leave things alone and put it back together once the new mainspring arrives and call it good.

- John

 

[svenedin]

Well done. The risk of wiggling the stud back and forth rather than pushing it out is that you could bend the delicate hairspring. You were obviously careful and all seems well. Those balance endstone jewel screws are often mangled but at least it shows the watch has been serviced in its long life.

 

[John Hinkey]

Well done. The risk of wiggling the stud back and forth rather than pushing it out is that you could bend the delicate hairspring. You were obviously careful and all seems well. Those balance endstone jewel screws are often mangled but at least it shows the watch has been serviced in its long life.

Yes, I wiggled it very very slightly back and forth, well within the flexibility of the spring, with very little upward force as I didn't want to have the needle nose pliers go flying when the stud came out. Apparently I'd had enough caffeine for the day as my hands were steady enough.

Now have to put it all back together . . .

 

[gmorse]

Hi John,

Clearly some of these small screws have been unscrewed for servicing before - that or the factory did a poor job installing them. Who knows.

Those damaged screw heads are certainly the result of careless handling of possibly the wrong sized screwdriver, and very commonly seen. You'll have to put it back together upside down, so I should practice that without lubrication a few times before oiling the endstone and doing it for the last time.

Those chips in the hole jewel aren't unexpected in view of the rest of the jewels, and if the watch runs adequately now it's clean, I wouldn't worry too much about that. The pivot shoulder should never touch that area anyway if the tip is running on the endstone as it should.

Really excellent pictures again!

Regards,

Graham

 

[John Hinkey]

Hi John,


Those damaged screw heads are certainly the result of careless handling of possibly the wrong sized screwdriver, and very commonly seen. You'll have to put it back together upside down, so I should practice that without lubrication a few times before oiling the endstone and doing it for the last time.

Those chips in the hole jewel aren't unexpected in view of the rest of the jewels, and if the watch runs adequately now it's clean, I wouldn't worry too much about that. The pivot shoulder should never touch that area anyway if the tip is running on the endstone as it should.

Really excellent pictures again!

Regards,

Graham

So you think it's OK if I put it together with this very cracked jewel:

and if it runs OK leave it as is? I have a couple of donor movements that I can get a replacement jewel from (I'd have someone else replace the jewel as it's beyond my current capabilities). It takes very little time to pull the bridge off to get it repaired.

I suppose there is victory in getting a new mainspring installed, movement back together and running well as the sterling silver case needs a new crystal, cleaning and dents taken out plus cleaning the dial and straightening the bent minute hand. Plenty more on this watch to do.

Thanks for the complement on the pics - I should take a pic of my work setup sometime soon.

- John

 

[gmorse]

Hi John,

...and if it runs OK leave it as is? I have a couple of donor movements that I can get a replacement jewel from (I'd have someone else replace the jewel as it's beyond my current capabilities). It takes very little time to pull the bridge off to get it repaired.

I'd be inclined to leave the jewels alone for now, fit the new mainspring, assemble it and see how it runs, (for a brief test), to establish whether there are any other problems with it. Then you'll know whether it's just the jewels that need attending to before you can call the movement project done and move on to the case and hands.

Regards,

Graham

 

[John Hinkey]

Decided to do a full inspection at high magnification of all the wheel pivots and the pallet jewels both to make sure they weren't worn and to see how my initial cleaning with Naptha and then L&R111 went (hand cleaning, no ultrasonic).

Used my digital caliper to hold onto the wheels and pallet to take the pictures.

Still some minor debris on the end of the pivot of the center wheel, but otherwise OK.

This wheel (second?) looks good:

Seconds wheel looks fairly clean but the shaft that the second hand goes on looks slightly bent, but that might be an illusion:

The escape wheel's pivots look good - needs a good final cleaning:

This is a cool image of the escape wheel:

Pallet definitely needs some more cleaning - it was way way way dirtier than this initially:

Now a look at the pallet pivots and a first look at the pallet jewels:

Needs some more cleaning for sure - boy that pallet jewel barely sticks out from the mount:

Here's the other one - it's just as dirty (though the bearing face is clean) and it too barely sticks out from the jewel mount:

And finally some images of the un-cleaned-at-all balance wheel and spring:

just got some one-dip alternative today to dunk this into.

Balance pivots & roller jewel looks good, just needs a thorough cleaning:

Perhaps I do need that ultrasonic cleaner . . .

That's it for now.

- J

 

[gmorse]

Hi John,

This wheel (second?) looks good:

The barrel is the first wheel, the centre is the second, then on down the train to the escape.

Seconds wheel looks fairly clean but the shaft that the second hand goes on looks slightly bent, but that might be an illusion:

This is the fourth wheel and the extended arbor is indeed bent. It can be straightened but it needs care and the best way is in a lathe, but leave it be for now.

Needs some more cleaning for sure - boy that pallet jewel barely sticks out from the mount:

The jewels are meant to be shrouded like that, the escape teeth should be centred on the jewels and never touch the metal pallet frame.

Balance pivots & roller jewel looks good, just needs a thorough cleaning:

The tips look flattened but you'll have to live with that as you haven't the tools to fix it. The impulse jewel is slightly out of upright, but again, leave it for now.

Regards,

Graham

 

[karlmansson]

Decided to do a full inspection at high magnification of all the wheel pivots and the pallet jewels both to make sure they weren't worn and to see how my initial cleaning with Naptha and then L&R111 went (hand cleaning, no ultrasonic).

Used my digital caliper to hold onto the wheels and pallet to take the pictures.

Still some minor debris on the end of the pivot of the center wheel, but otherwise OK.
View attachment 706184

This wheel (second?) looks good:
View attachment 706195

Seconds wheel looks fairly clean but the shaft that the second hand goes on looks slightly bent, but that might be an illusion:
View attachment 706185

The escape wheel's pivots look good - needs a good final cleaning:
View attachment 706188

This is a cool image of the escape wheel:
View attachment 706187

Pallet definitely needs some more cleaning - it was way way way dirtier than this initially:
View attachment 706189

Now a look at the pallet pivots and a first look at the pallet jewels:
View attachment 706190

Needs some more cleaning for sure - boy that pallet jewel barely sticks out from the mount:
View attachment 706191

Here's the other one - it's just as dirty (though the bearing face is clean) and it too barely sticks out from the jewel mount:
View attachment 706192

And finally some images of the un-cleaned-at-all balance wheel and spring:
View attachment 706193
just got some one-dip alternative today to dunk this into.

Balance pivots & roller jewel looks good, just needs a thorough cleaning:
View attachment 706194

Perhaps I do need that ultrasonic cleaner . . .

That's it for now.

- J

Pithwood and a little bit of isopropyl alcohol will clean those pivots at least. The ultrasonic isn't end all be all of watch cleaning, often you need to mechanically clean off old natural oils that have formed a resin. Be careful and poke the pivot ends into a dense section of pithwood, dry first, and then into some that has soaked up some alcohol. Then you can clean the entire balance as you please. Check all other pivots in this way and proceed the same way.

"Clean" is a very subjective term sometimes. Sometimes it means that someone has made an attempt at cleaning a watch. Other times it means actual, chemically clean, oil free surfaces. You should strive for the latter but need watch to check you work. You microscope looks like an excellent way to do that! A great learning tool!

Regards
K