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Testing an automatic mainspring for slippage in a barrel


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I have a Citizen 33J cal 5204 which is driving me nuts trying to get decent amplitude.

I'm pretty sure it's the mainspring slipping in the barrel. This is the procedure from the service manual -

Where it says 'Check the number of rotations by re-winding the mainspring' - does that mean letting down the mainspring ?

As the arbor has a slit in the top, it's easy to watch it. If I wind it about 10 rotations, then let the spring down, the arbor only turns about 1 revolution :huh:

I use Moebius 8217 on the barrel wall. I thought I might have used too much, so cleaned it and put very little on, and fitted a new mainspring.

Any ideas ?

Thanks

(the pic is the old spring before cleaning !)

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WIN_20190216_15_57_51_Pro.jpg

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You are testing it correctly I think. It sounds like the brake spring has set and become too curved. It needs to be straightened or even curved in the opposite direction so that it grips the outer wall of the barrel more tightly.

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12 minutes ago, Klassiker said:

You are testing it correctly I think. It sounds like the brake spring has set and become too curved. It needs to be straightened or even curved in the opposite direction so that it grips the outer wall of the barrel more tightly.

It's a new spring. 

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37 minutes ago, Klassiker said:

Oh, sorry. I understood you had cleaned and re-used the old spring.

I did to start with, but as the amplitude was so poor, I fitted a new spring.

I wonder if the surface condition of the barrel wall could be the problem ?

I've been looking for a donor movement - but the 52**/54** movements aren't common.

Edited by mikepilk
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something doesnt look right on the outer most coil. did you use a mainspring winder to install the MS? re-winding does mean letting it down i would think but how are you unwinding it? your not just simply releasing the click are you. 

ok this is what i suggest: take barrel out and remove lid. turn the arbor with a driver and watch the coils wind up, while keeping barrel between your fingers on a flat surface. you will see if its slipping right away.

NOW i think this IS your issue: if the mainspring starts to pop out as you are winding then thats most likely due to an improper install, and when the lid is on the coils are rubbing up against the barrel lid adding friction and resistance to the MS causing loss in the power which equals Low amplitude.

check that and get back to us

Edited by saswatch88
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6 hours ago, saswatch88 said:

 

NOW i think this IS your issue: if the mainspring starts to pop out as you are winding then thats most likely due to an improper install, and when the lid is on the coils are rubbing up against the barrel lid adding friction and resistance to the MS causing loss in the power which equals Low amplitude.

check that and get back to us

Forgive this beginner question but what defines an improper instal?

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11 hours ago, saswatch88 said:

something doesnt look right on the outer most coil. did you use a mainspring winder to install the MS? re-winding does mean letting it down i would think but how are you unwinding it? your not just simply releasing the click are you. 

ok this is what i suggest: take barrel out and remove lid. turn the arbor with a driver and watch the coils wind up, while keeping barrel between your fingers on a flat surface. you will see if its slipping right away.

NOW i think this IS your issue: if the mainspring starts to pop out as you are winding then thats most likely due to an improper install, and when the lid is on the coils are rubbing up against the barrel lid adding friction and resistance to the MS causing loss in the power which equals Low amplitude.

check that and get back to us

I agree the spring doesn't look right in that pic. There were signs that it had been rubbing on the barrel lid.  One reason I changed it was the height was 1.1 mm, whereas the original spec shows 1.2 mm

I do use a spring winder, though as these wind the 'wrong way' I have to wind it in to the next smaller winder, then transfer it to the correct size to get it the right way round.

I unwind it by releasing the click whilst controlling the crown in my fingers.

I agree it's a good idea to remove the lid and watch it wind, though the slot in the arbor isn't deep enough for a screwdriver, so I'll have to try and use a pin vice.

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5 hours ago, Lc130 said:

Forgive this beginner question but what defines an improper instal?

Correct question LC,  I wonder if there is a correct lesson , put out by a reputable school or manufacturer. 

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1 hour ago, mikepilk said:

I agree the spring doesn't look right in that pic. There were signs that it had been rubbing on the barrel lid.  One reason I changed it was the height was 1.1 mm, whereas the original spec shows 1.2 mm

I do use a spring winder, though as these wind the 'wrong way' I have to wind it in to the next smaller winder, then transfer it to the correct size to get it the right way round.

I unwind it by releasing the click whilst controlling the crown in my fingers.

I agree it's a good idea to remove the lid and watch it wind, though the slot in the arbor isn't deep enough for a screwdriver, so I'll have to try and use a pin vice.

wind the wrong way? then you just wind the spring into the winder in the opposite side going clockwise or counter clockwise. and transferring it to correct size do you mean going from smaller winder to larger winder?  when you say size do you mean size of the arbor on the winder so the hole end is shaped right? if thats the case then that should not dictate wether you use a smaller winder. you should select your winder based on the size of the barrel not the arbor. most mainsprings dont have the correct shape at the end to fit the arbor in the watch, so you have to shape it. you can use a pair of wire beading pliers to shape the hole end once its in the barrel. some of these pliers are made of nylon so you dont have to worry about marking or burring the mainspring or barrel.

also if there was a 1.1 in there before and you replaced it with a 1.2 now your seeing signs of rubbing then i would say there was a reason it may have had the 1.1. and you should replace it with the same.

LAST NOTE: SEE MY PIC

looking at the picture it looks as if the notch on the wall of the barrel is at the bottom and the break is against it coming from its left side, and then looking at the hole end its in the clockwise direction. if iam right on my observation then the MS has been installed in the wrong direction, hence the slipping. the MS should wind in the opposite direction of the notch on the barrel wall. as you can see with may arrows that there is nothing stopping the MS from sliding against the wall of the barrel.

WIN_20190216_15_57_51_Pro.thumb.jpg.e6ed8194173b50f890e3426a8e357ef9.jpg

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I don't think the spring is broken, that's just the bridle overlapping itself and is normal.

If you try to wind a spring in a barrel with the lid off, the coils WILL jump out. It's not a sign of a deformed spring. And it's a common method to get "backwards" springs in to use a winder one size too small, and transfer to the proper winder then barrel. And if original is 1.2mm high, it's pretty certain that's the correct height. Many barrels will show signs of rubbing after years of use, see above about coils jumping out. The lid and barrel bottom keep them in, they rub.

 

As to the slipping issue, it is probably a combination of a worn barrel wall and incorrect grease. The 8217 is from the old Glissalube line, which changed designation to fit the numerical system Moebius uses. The 8213 (old Glissalube A) is strong braking, recommended for brass barrels. The 8212 (old Glissalube B ) is weak braking and recommened for aluminum barrels. The 8217 (old Glissalube 20) is considered "normal" braking but Moebius lists it as "soft" for all barrels.

Some auto barrels have notches around the wall, some are smooth. Both can get worn to where they slip too easily. If it's your own watch, a rub around the inside with rough emery paper may do the trick. Going to a more "braky" grease could do it too. Maybe both, maybe you just need a new barrel and the more braky grease.

glissalube.jpg

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1 hour ago, nickelsilver said:

I don't think the spring is broken, that's just the bridle overlapping itself and is normal.

If you try to wind a spring in a barrel with the lid off, the coils WILL jump out. It's not a sign of a deformed spring. And it's a common method to get "backwards" springs in to use a winder one size too small, and transfer to the proper winder then barrel. And if original is 1.2mm high, it's pretty certain that's the correct height. Many barrels will show signs of rubbing after years of use, see above about coils jumping out. The lid and barrel bottom keep them in, they rub.

 

As to the slipping issue, it is probably a combination of a worn barrel wall and incorrect grease. The 8217 is from the old Glissalube line, which changed designation to fit the numerical system Moebius uses. The 8213 (old Glissalube A) is strong braking, recommended for brass barrels. The 8212 (old Glissalube B ) is weak braking and recommened for aluminum barrels. The 8217 (old Glissalube 20) is considered "normal" braking but Moebius lists it as "soft" for all barrels.

Some auto barrels have notches around the wall, some are smooth. Both can get worn to where they slip too easily. If it's your own watch, a rub around the inside with rough emery paper may do the trick. Going to a more "braky" grease could do it too. Maybe both, maybe you just need a new barrel and the more braky grease.

 

The barrel wall doesn't look too bad, a bit worn and smooth. I'll try to get a replacement barrel and some 8213.

WIN_20190407_14_46_43_Pro.jpg

WIN_20190407_14_47_45_Pro.jpg

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I disagree with any test, wind, count with lid off and barrel in open.

MS can come out flying and hurt someone.

I grease or whatever you want to do, instal the barrel with retaining bridge and ratchet wheel screwed on.

-- wind through the ratchet say with your screw driver, listen close for the sound of power discharge from the barrel (it will discharge at some point). You want to count the number turns on the ratchet wheel so mark a dot on the wheel and count the number of turn the dot goes by.

Dispower the barrel fully, wind again, stop winding just short of the number you counted before power discharge.

Let the watch run on bench and note how long it runs to stop. 

That is the actual power reserve your watch retains.

The main advantage of this approach is, that you can still see with your eyes. Both of them.:lol:

Regards

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NUCE i do wind test with lid off all the time, if the barrel is secured  and arbor tightly gripped while winding then it will not pop out unless the spring is badly warped and you dont keep a tight grip on the barrel. i grip from the sides of barrel and allow the edge of my fingertips to rest over the edge of the barrel on top of the spring ensuring it wont come out. it is the best way to see what going on under the hood in my opinion and saves on the guessing games and i never had one jump out on me.

NICKEL i have to both agree and disagree with popping up  of the spring. usually when i observe the spring with lid off it will pop up a bit due to the hook on the arbor being a tiny bit higher than the center of the hole in the end. but it should never come out any higher than the arbor for that would mean excessive rubbing and friction on the lid. nor should the spring be coning up at the "un-winded" rest position. it should lay perfectly flat which it seems to do in the pics. usually it will only take a few rotations of the spring to see this and can be stopped before spring pops out. 

these pliers work wonders when it comes to shaping the hole end of the spring. ALSO did anyone look at the picture i attached in my last post does anyone agree that it looks like the MS is installed in the wrong direction?? when compared to pics of barrels i just attaches you can see they are all winding in the opposite direction of the notch and break

 

pl8564-nylon-jaw-pliers-round-nose.jpg

rolex-factory-spares-7822-7825-7827-barrel-bridge-part-main-spring-complete-barrel-cal-automatics-1520-1530-1560-1570.jpg

mainspring.jpg.b23d915ad4ea420532ae5ecf95ae3b26.jpg

Mainspring-and-Barrel-JimInOz-voa-omegaforums-.jpg

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Sas if you can fully wind an auto spring with the cap off and observe the slipping action without the spring jumping out you have almost certainly made a deal at the crossroads so I won't argue with you.

Do keep up though, the OP was clear that this spring goes in opposite of conventional, i.e. cap is on the top not the bottom. Thus using two winders, as most are designed with arbors to wind conventional springs, and also why bergeon makes winder sets with both right and left hand arbors.

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25 minutes ago, nickelsilver said:

Sas if you can fully wind an auto spring with the cap off and observe the slipping action without the spring jumping out you have almost certainly made a deal at the crossroads so I won't argue with you.

Do keep up though, the OP was clear that this spring goes in opposite of conventional, i.e. cap is on the top not the bottom. Thus using two winders, as most are designed with arbors to wind conventional springs, and also why bergeon makes winder sets with both right and left hand arbors.

i understand that he said it was opposite of conventional, but that doesnt matter. the spring should still wind opposite the notch/lip in the barrel no matter what the direction is. if it doesnt then there is nothing stopping the spring from sliding around the barrel walls when winding.

and i dont fully wind it that would be a difficult task 100%, i just go about 1-5 turns. in that amount of turns you can tell if MS is warped and within the first turn you see if its slipping off the arbor.

Edited by saswatch88
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i understand that he said it was opposite of conventional, but that doesnt matter. the spring should still wind opposite the notch/lip in the barrel no matter what the direction is. if it doesnt then there is nothing stopping the spring from sliding around the barrel walls when winding.
and i dont fully wind it that would be a difficult task 100%, i just go about 1-5 turns. in that amount of turns you can tell if MS is warped and within the first turn you see if its slipping off the arbor.
It's automatic, right in the title. The gap you see is the bridle overlapping as it should do.
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8 minutes ago, nickelsilver said:

It's automatic, right in the title. The gap you see is the bridle overlapping as it should do.

yes but again there has to be something in the barrel for the bridle to lean against to stop it. Right mainspring, properly oiled and installed yet still slipping. so what it is then? 

OP can you please take a pic of the barrel without the MS installed. thanks

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yes but again there has to be something in the barrel for the bridle to lean against to stop it. Right mainspring, properly oiled and installed yet still slipping. so what it is then? 

OP can you please take a pic of the barrel without the MS installed. thanks

Have you ever worked on an automatic watch?

The whole thread is about the spring slipping prematurely, which, as explained above, can be due to numerous issues and some barrels have 6 or so notches (which are radiused) some are smooth. OP has smooth. It has worn through the original plating, showing brass. Moebius has a braking grease just for brass, which is incidentally their "strong" braking grease. It's all in the thread.

 

OP also posted a pic of barrel without spring already btw.

 

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43 minutes ago, nickelsilver said:

Have you ever worked on an automatic watch?

The whole thread is about the spring slipping prematurely, which, as explained above, can be due to numerous issues and some barrels have 6 or so notches (which are radiused) some are smooth. OP has smooth. It has worn through the original plating, showing brass. Moebius has a braking grease just for brass, which is incidentally their "strong" braking grease. It's all in the thread.

 

OP also posted a pic of barrel without spring already btw.

 

UM yes i have. many of them. mostly ETA and seiko, never a citizen though. and i do know some older automatics have smooth barrels and rely only on the bridle for slipping. vintage Seikos for example has a smooth barrel. modern automatics such as ETA 7750 are notched and i dont see photo of empty barrel i just see a pic of broken file. and I never said I was right, it was an observation i made in order to give a possible solution. the photo i posted with red arrows is what looks like a notch in the barrel.

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21 minutes ago, saswatch88 said:

vintage Seikos for example has a smooth barrel.

Even current ones do have the same. So far it has been a dogma that the MS of an automatic mov.t has to slip virtually unhindered in the barrel, probably for fear that continued stress would break it something. However Nomos has now introduce in its DUW 601 a "rotor brake" system, that to say, no slipping anymore.

https://www.watchtime.com/featured/nomos-caliber-duw-neomatik-6101/

Edited by jdm
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As @nickelsilver pointed out, the barrel has worn through the nickel plating to brass. 

I therefore plan to change the barrel, when I can find a replacement - there are some NOS on ebay but I don't know the part number. Anyone got a reference to Citizen parts lists? I have the technical/service manuals but can't find any parts list.

With a replacement barre l+ new spring + 8213, I should hopefully get decent amplitude !  

 

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As [mention=4990]nickelsilver[/mention] pointed out, the barrel has worn through the nickel plating to brass. 
I therefore plan to change the barrel, when I can find a replacement - there are some NOS on ebay but I don't know the part number. Anyone got a reference to Citizen parts lists? I have the technical/service manuals but can't find any parts list.
With a replacement barre l+ new spring + 8213, I should hopefully get decent amplitude !  
 
Haha weeelll in my experience low amplitude is rarely due to the mainspring. But you did have the wrong height and the thickness could have been off a bit too, just 0.005mm makes a big difference.
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2 minutes ago, nickelsilver said:

Haha weeelll in my experience low amplitude is rarely due to the mainspring. But you did have the wrong height and the thickness could have been off a bit too, just 0.005mm makes a big difference.

I'm pinning my hopes on it being the mainspring. I've examined every jewel/pivot under the microscope - the gear train runs beautifully, (tried all individually and together) as does the new balance (nothing touching). The pallet/jewels look good. Had it stripped down about 6 times trying to find the cause !  

Currently showing just 215 deg.

Out of interest I looked up the coefficient of frictions (sliding) for brass and nickel :

nickel to mild steel is 0.64,  brass to mild steel  0.44  (couldn't find numbers for spring steel)

So when the nickel wears through, the friction drops about 30%

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