Tightening the barrel spring

[tomh207]

@Jon

i like your tweezer idea, ideal use for worn or crappy tweezers we al likely have kicking about in our toolbox.

Tom

[Neverenoughwatches]

On 1/1/2024 at 3:41 PM, Jon said:

Undergreasing the actual spring, not the barrel wall.

So, when the mainspring has been cleaned it is greased. If the entire length of the mainspring hasn't been greased enough or not at all, (the spring has to be able to slide coil over coil) then when winding the watch manually there might be a scratchy feeling with the coils not sliding over each other because of the lack of grease and too much friction of the coils over coils.

The scratchy feeling may also be because the spring has a slight helix and scrapes on the barrel and/or cover when winding, which can also fluctuate power output, therefore a loss of amplitude.

There are generally three types of braking grease for the barrel walls depending on what the barrel is made of. Moebius 8212 is meant to be used on aluminum barrels. This grease has a moderate braking effect. Moebius 8213 is meant for brass barrel walls and isn't quite as thixotropic as 8212, but is more viscous than all of them so provides slightly more braking. The goldilocks of them all is Moebius 8217 which can be used on all barrel types, This grease is the least viscous but still has a fairly good thixotropic effect. The thixotropic effect is when the grease is under load or pressure it changes from a viscous grease to more fluid like an oil. Moebius 9415 is a thixotropic grease for pallet stones because of this effect; it is better than 9010 which used to be used. Oils and greases have developed a lot in the last decade

On old-style automatics, the 'slipping bridle' was a separate piece of spring that had to have the correct springiness to dictate when the bridle slipped and therefore the mainspring. This still had to have braking grease on the barrel wall. The mainspring looked like any manual spring with a hook on the end that caught the hook of the slipping bridle. It was more the shape of the bridle that determined when the bridle and spring slipped rather than relying on how much braking grease was on the barrel wall. The flatter the spring (when out of the barrel) the slip will happen later, also creating the most amplitude, the more curved the slipping bridle, the spring will slip earlier which may result in not enough torque being generated and a loss of amplitude.  On modern automatic mainsprings, it is the bridle that pushes the mainspring against the barrel wall and creates that force so the end of the spring will jump from indentation to indentation in the barrel wall. On old-style automatics, a lot of the time the slipping bridle has been removed and a modern spring has been used, but there aren't any indentations on the barrel wall, just a smooth wall. Depending on how much and which type of grease is used on the barrel wall, as well as the state of the wall will determine when the spring will slip. Also, some older automatics will look like having quite a low amplitude fully wound and after 48 hours after oiling and greasing, let's say 250 degrees, once the auto module and rotor are replaced and the watch is fully wound and the rotor is spun  a little, because the spring has total full torque now you can see the amplitude increase as much as 30 or so degrees.

Here are some slides from a lesson I wrote for my students. As you can see the slipping bridle was set incorrectly which I found when taking the movement apart. It is important the bridle has room to close up properly, which highlights the point that "just because you found it that way doesn't make it the correct way" So, don't ever assume how you found it is how it should be!

I know you always recommend a new spring Jon, but what about pulling a helixed spring back through itself. I have tried it a few times on scrap springs and it will reduce even sometimes remove it altogether depending on the type of spring. 

On 1/2/2024 at 7:27 AM, Waggy said:

I have a question on the above, I used to do this, then got out of the habit of doing it when I saw a few watchmakers on YouTube apply a few spots of 8200 to the coils of the cleaned spring after it has been reinserted into the cleaned barrel, with the assumption that the grease will work its way into the spring in a relatively short time. The reasons for me doing it this way is that if you use the paper or finger methods on the spring outside the barrel quite often you cannot get to the innermost coils easily, and if you try there is a danger you could stretch/deform them or leave behind bits of paper - also it seems quicker and easier to do it when inside the barrel....but now I just want to make sure if greasing the spring inside the barrel is good practice and if not, why not?

You're probably not going to get a good even film of grease over the full length and profile of the spring that way, maybe in time but that might be leaving it to chance. Oil maybe would, but back to the basic principle of # if it revolves oil it,  if it slides grease it #. Might also be a reason why folk complain of issues with mainspring winders, a pre greased spring is going to slip out of the winder barrel and into the mainspring barrel much easier than a dry one, adding a touch to winder wall also helps. Keep winders boxed and brush out before using them.

On 1/2/2024 at 7:07 AM, tomh207 said:

How I see it is 8200 can be used to grease the spring, not the barrel using a piece of watchmakers tissue lightly loaded with the grease, folded over the spring and drawn along the length to give a very light smear of grease. The wall of the barrel should be greased with braking grease separately with something like 8217.

 

Tom

I use greased watch paper in a pair of tension and tip adjusted reverse lock tweezers. Makes life a little easier and gives you an extra hand to control the spring. Same tweezers i use to clean the spring with a small strip of chamois after ipa soaking the spring. Clean and grease in one operation. 

On 1/2/2024 at 10:25 AM, VWatchie said:

That's the method I apply as well and for the same reasons. I believe I started doing it having seen Kalle Slaap at Chronoglide doing it. He applied four tiny drops of HP-1300 to the spring after it had been pushed into the barrel. See if I can find that video again... Anyway, like you, I still wonder if it generally would be considered good practice or not, but I think it should be OK. We all know that the number one priority of oil is to spread as much as it can.

 

no i don't get that at all. Oil could spread, could excess oil make its way out of the barrel if the base or lid has a cut out ? A fully greased spring seems a better option imo. 

On 1/2/2024 at 10:30 AM, Waggy said:

And there is no problem in a watch which cannot be solved by the application of more oil 

 

22 hours ago, VWatchie said:

Do we all agree that the purpose of braking grease is more or less perfectly described by @LittleWatchShop in this post (thanks for the research!)? It sounds spot-on to me. Would the pros among us, like @Jon, agree

Seen it suggested many times breaking grease described as anti slippage grease. I feel there needs to be some clarification on this as that makes no sense to me whatsoever. 

21 hours ago, Jon said:

make a pair of greasing tweezers with chamois leather on the inside. The chamois is greased with 8200 or 8300 is best in hot climates and the entire length of the spring is lightly greased. You know when enough has been applied as it is the feel of the grease on the spring and how easily those greasing tweezers slide over the spring. If you have greased the spring too much you'll see excess on top of the spring when you use your winder and it is within the barrel. If you haven't greased the spring enough then put a few small drops of grease on the top of the spring like Kalle Slappe does. There are many ways to skin a cat here. I can only say what works best for me. After you've greased a few mainsprings you'll get a feel for what the right amount is on the spring. If it is too much and you see pools of grease on the spring when in the barrel, then mop up the excess with some rodico. The great thing about making these greasing tweezers is you can get into the innermos

Thats almost exactly what i have cept my tweezers are locking, just frees up a hand. Either greased watchpaper or chamois. 

[VWatchie]

On 1/3/2024 at 1:36 PM, Neverenoughwatches said:

no i don't get that at all. Oil could spread, could excess oil make its way out of the barrel if the base or lid has a cut out ? A fully greased spring seems a better option imo. 

Yes, oil always spreads as far as it can to any surface it can reach - I believe there's a fancy word for it which I can't remember - unless we take measures to prevent it like using epilame. But epilame is not an option as it should never be applied to a mainspring. So, using oil we'd have to be more careful with the amount applied. Grease also spreads if applied excessively, but is perhaps not as prone to spread as oil?! Anyway, dabbing on thick oil like HP-1300 is faster and more convenient, but getting the right amount could be more difficult. I agree, greasing the spring seems more controlled, but is it worth the extra hassle, and purchase of grease? (Open, honest question, not rhetorical).

Edited January 4 by VWatchie

[CYCLOPS]

I just hope the bridle isn't broken off.....

[VWatchie]

On 1/2/2024 at 4:44 PM, Jon said:

I make a pair of greasing tweezers with chamois leather on the inside.

Great tip. Bergeon has dedicated tweezers for this purpose but as usual the price is, shall we say, a bit steep?! 

How do you get the chamois leather to stick to the tweezer tips? Where can you get chamois leather? I want to make my own.

A grease frequently used as a braking grease we haven't talked about is Kluber Chronogrease P125. I'm pretty sure @nickelsilver mentioned using it for all types of barrels. It's the grease I use. And mind you, it is only £23,000.00/Kg (including VAT) 

28 minutes ago, CYCLOPS said:

I just hope the bridle isn't broken off.....

You need to elaborate if we are going to have a chance to understand it and comment.

Edited January 4 by VWatchie

[Neverenoughwatches]

1 hour ago, VWatchie said:

Yes, oil always spreads as far as it can to any surface it can reach - I believe there's a fancy word for it which I can't remember - unless we take measures to prevent it like using epilame. But epilame is not an option as it should never be applied to a mainspring. So, using oil we'd have to be more careful with the amount applied. Grease also spreads if applied excessively, but is perhaps not as prone to spread as oil?! Anyway, dabbing on thick oil like HP-13000 is faster and more convenient, but getting the right amount could be more difficult. I agree, greasing the spring seems more controlled, but is it worth the extra hassle, and purchase of grease? (Open, honest question, not rhetorical).

I have done both, 4 drops of oil on top of the wound spring and pre applying grease before winding up. You can see the oil visibly dissipate into the spring but its left to chance how much of that will fully coat it. I wouldn't want to choose the easy option because of just that. My rule of thumb is revolve oil, slide grease, it could be argued that a winding and unwinding spring does both but i lean towards that the coils slide within each other. I did read somewhere that the coating is merely there as an anti corrosion application, but that doesn't seem totally correct, its also reducing friction. I've even heard of folk using candle wax to grease the spring, sounds like a very old outdated method without understanding how the effects of properties of different waxes have on a coiling and uncoiling spring.

38 minutes ago, VWatchie said:

How do you get the chamois leather to stick to the tweezer tips? Where can you get chamois leather? I want to make my own.

I chose to use locking tweezers, makes it a little easier to change out the paper or leather and holds the spring in place handsfree I also like Jon's idea as well , i copied that from the nekkid watch maker ages ago but slightly preferred my idea. Chamois leather most hardware stores in the UK, traditionally used to wipe down your car after washing it, my dad was doing it 50 years ago, and the old faithful piece of equipment of the window cleaner. Thats how i aquired mine from our cleaner.

[VWatchie]

4 hours ago, Neverenoughwatches said:

I did read somewhere that the coating is merely there as an anti corrosion application, but that doesn't seem totally correct, its also reducing friction.

I read the same somewhere and I've had the same thought. It just wouldn't feel right keeping the spring dry. Anyway, winding it in and pushing it out dry is never any problem with my Master Craft Mainspring Winder. This also means I don't have to fiddle around so much with the spring exposing it to all sorts of contaminations.

4 hours ago, Neverenoughwatches said:

You can see the oil visibly dissipate into the spring but its left to chance how much of that will fully coat it.

Yes, that's what I worry about too. Not so much that it wouldn't become fully coated (oil always spreads as much as it possibly can) but rather causing the most classical error of them all. Over oiling! To get it right you would have to experiment. Oil it, use it, take it apart and examine it. I might be too lazy for that so I think I'll go back to the greasing method where you can see and assess the amount of grease over the entire length of the spring. Hmm...

[Jon]

5 hours ago, VWatchie said:

How do you get the chamois leather to stick to the tweezer tips? Where can you get chamois leather? I want to make my own.

Superglue on the tweezers to stick the chamois leather. You can buy the chamois or a faux chamois at most auto parts stores for cleaning your car. When the chamois has had its day, soak the tweezer tips in acetone and start again with fresh chamois.

[VWatchie]

On 1/1/2024 at 4:41 PM, Jon said:

If the entire length of the mainspring hasn't been greased enough or not at all,

Greasing the entire length of the spring, wouldn't the grease of the utmost coil interfere or get mixed with the braking grease? For this reason, I used to skip greasing the last bit (30 mm or so) of the spring. Now that I dab on HP-1300 on the spring after having pressed it into the barrel I don't care too much as I can't control it.

5 minutes ago, Jon said:

Superglue on the tweezers to stick the chamois leather. You can buy the chamois or a faux chamois at most auto parts stores for cleaning your car. When the chamois has had its day, soak the tweezer tips in acetone and start again with fresh chamois.

Just perfect Jon! Thank you! 

[Neverenoughwatches]

25 minutes ago, VWatchie said:

Greasing the entire length of the spring, wouldn't the grease of the utmost coil interfere or get mixed with the braking grease? For this reason, I used to skip greasing the last bit (30 mm or so) of the spring. Now that I dab on HP-1300 on the spring after having pressed it into the barrel I don't care too much as I can't control it

Makes perfect sense watchie, you could always just not coat the outside  of the last coil,  but how finicky do we want to be. I know how particular you are watchie, nothing at all wrong with that attitude. 

[eccentric59]

8 hours ago, VWatchie said:

I believe there's a fancy word for it

I think capillary action is the term you are looking for.

On 1/3/2024 at 7:36 AM, Neverenoughwatches said:

breaking grease described as anti slippage grease.

Get ready for some fancy words ..   A materials lubricity is measured as a function of its coefficient of friction, or the amount of resistance between two surfaces under specific force. The concept of a braking or anti-slip grease is to provide a fairly high coefficient of friction without becoming an adhesive. This permits the bridle to move against the barrel wall under quite a bit of force without damaging either. While braking grease is still a grease, it's not a lubricant.

[Neverenoughwatches]

24 minutes ago, eccentric59 said:

I think capillary action is the term you are looking for.

Get ready for some fancy words ..   A materials lubricity is measured as a function of its coefficient of friction, or the amount of resistance between two surfaces under specific force. The concept of a braking or anti-slip grease is to provide a fairly high coefficient of friction without becoming an adhesive. This permits the bridle to move against the barrel wall under quite a bit of force without damaging either. While braking grease is still a grease, it's not a lubricant.

The confusion for me came from the comparison between a dry barrel wall and a greased wall. In contradiction a braking grease will allow a spring to slide along the wall being it at a set moment of force applied as opposed to an ungreased wall that i expect wont allow much slippage at all. The term breaking i guess just comes from the comparison between different greases, they coud just as easily be known as different slippage greases.

[eccentric59]

The term is somewhat oxymoronic (as opposed to me, who is usually just plain moronic  ). Think of it like giving parts a final dip in IPA to absorb any residual moisture. You have to wet it to make sure it's dry. 

Ain't chemistry grand?

[RichardHarris123]

The steel spring would slide along the brass barrel wall but the friction would be increased.  Probably damaging the barrel wall and contaminating the barrel with microscopic brass filings. 

[HectorLooi]

Actually, it is even more complicated. It lubricates because it forms a film on the metal surfaces, preventing metal-to-metal contact. But the "braking" effect is due to the viscosity of the grease. The friction between the molecules of the grease gives resistance to slippage.

An easier to understand example would be the focusing ring on a camera lens. If the parts were dry, the metal would rub against each other and could actually squeal and make your hair stand. If normal grease was applied, the focusing ring would turn so easily that it wouldn't feel right. So, a special type of grease, similar to braking grease, is used. But in photography, it's called a damping grease, adding even more confusion.

So is braking grease = damping grease? Probably not. Or else why would we be paying for Kluber Chronogrease? Hmmm....

[RichardHarris123]

Also to take into consideration is the non Newtonian properties of the gease.  It's viscosity will change with the work applied. 

[Neverenoughwatches]

2 hours ago, RichardHarris123 said:

The steel spring would slide along the brass barrel wall but the friction would be increased.  Probably damaging the barrel wall and contaminating the barrel with microscopic brass filings. 

It does, ive tried it. In fact there's enough barrels here to try every experiment that anyone can imagine up.

1 hour ago, HectorLooi said:

The friction between the molecules of the grease gives resistance to slippage.

Or to look at it another way.  It lubricates in a way that reduces resistance to slippage depending what its applied to and compared to a grease that doesn't reduce resistance as much.

[RichardHarris123]

7 minutes ago, Neverenoughwatches said:

fact there's enough barrels here to try every experiment that anyone can imagine up.

Shooting fish in a barrel, try that one. 

[Neverenoughwatches]

1 hour ago, HectorLooi said:

If the parts were dry, the metal would rub against each other and could actually squeal

Metal galling.

9 minutes ago, RichardHarris123 said:

Shooting fish in a barrel, try that one. 

Lol dont tempt me, you know I'll give it a go.

43 minutes ago, RichardHarris123 said:

Also to take into consideration is the non Newtonian properties of the gease.  It's viscosity will change with the work applied. 

Thixotropic ? Some are

Edited January 4 by Neverenoughwatches

[RichardHarris123]

Read this and watch the video.  https://fyfluiddynamics.com/2011/02/theres-more-to-non-newtonian-fluids-than/

[LittleWatchShop]

So, a non-Newtonion fluid is thixotropic?  I did not know that.  I wondered of MOS2 was a non-Newtonion fluid but could not find any support for that in my search (but I did not spend much time).

 

[Waggy]

18 hours ago, Neverenoughwatches said:

I chose to use locking tweezers, makes it a little easier to change out the paper or leather and holds the spring in place handsfree

Looks like I have a new project for the weekend, going to try the locking tweezers and chamois leather method - as usual great advice from the group and very much appreciated