2 piece automatic mainspring

[AshF]

Hi all,

I'm working on an old CYMA bumper automatic and the spring is the 2 piece early automatic type.  After a quick search of this forum I found a link to this which said that both pieces should be oiled with an "oily rag" and the barrel wall oiled with pegwood. 

https://watchguy.co.uk/wp-content/uploads/2012/12/Repairing-Omega-self-winding-watches-bumper.pdf

Would 8200 suit this?  Any advice?  I've got a new non auto mainspring that is very similar to the one pictured.

Thanks,

Ash.

[JohnR725]

Your mainspring looks kind of set? As this is an automatic watch special grease is required on the outer wall known as breaking grease. Breaking grease is designed to hold the mainspring in place until it's wound up far enough then it will break free function as a grease and release some of the power. Otherwise the mainspring wind up tight and the automatic will break. A special breaking grease is applied to the outer wall. Then as you're using an older spring you can use the 8200 lubricate that. It was a modern spring you wouldn't have to use any lubrication on the spring except the wall itself.

Than if you look up your watch she should bill a find a modern automatic spring. On the modern Springs they attached the little bit at the end it's all one spring.

Then one of the problems with service guides are they can be very helpful but they can also be dated as there's new and different ways of doing things. I'm attaching some images of how you're supposed to do modern breaking grease. You will note they're not putting any lubrication on the spring itself as that's considered prelubricated or basically doesn't require lubrication. Only the barrel wall.

Then in case you get tempted the use 8200 is a breaking grease it will work very very poorly. That's because it's a grease with almost 0 breaking ability. It means as soon as the watch starts the wind up it will slip you'll probably get an hour or two of running and that sets won't even run overnight. So unfortunately really do need breaking grease.

 

 

[jdm]

1 hour ago, JohnR725 said:

As this is an automatic watch special grease is required on the outer wall known as breaking grease. 

Dictation software failure? Braking grease. My personal opinion, if one isn't in the mood of spending and waiting, try first with the wall cleaned and dry, see what kind of power reserve that gives you.

[JohnR725]

48 minutes ago, jdm said:

Dictation software failure?

Some days the dictation software doesn't like me. Then there's human error failure the problem of dyslexia not always catching things. There's a lot of places where it uses the wrong word sometimes I catch it sometimes I don't sometimes it just does goofy things sometimes I don't quite pronounce things correctly then things get even worse.

[AshF]

Thank you @JohnR725 for your detailed response, I didn't know that about greasing the correct side of drum notches.

I do have breaking grease that I use for normal automatics with normal automatic mainsprings.  However this old watch I believe predates automatic mainsprings and breaking grease (please correct me if I'm wrong) and uses the special bridle to achieve this.  From the document I linked it talks about the bridle being lifted slightly by a wound mainspring allowing it to slip.  The document says to oil the spring, bridal and barrel wall with "oil" but neglects to say which oil (unless I've missed that part).  I would expect that the best oil used at that time would approximate 8200 so that is what I've used.

I get what you say about using modern replacements and techniques but in this case I'd like to keep it as original as possible.  I have replaced that set mainspring with something very similar which fits the barrel (with bridle) and arbour perfectly.  When winding it up you can feel the moment of slip at full (or nearly full) wind.  On a full wind it's been running for 12 hours (without the automatic module) with an amplitude of 230.

[JohnR725]

1 hour ago, AshF said:

neglects to say which oil

Possibly was in a separate guide that you don't have? Notice at the very beginning of  the PDF that it's number one? This is one of the clever things Omega's done over the years realizing that generic things applied in watch repair. So generic things go in separate documentation that most people don't even know exists. 

1 hour ago, AshF said:

I get what you say about using modern replacements and techniques but in this case I'd like to keep it as original as possible.

If I read the description on how the mainspring works its identical to modern mainsprings. It just comes in two pieces and I'm guessing they didn't have breaking grease back then? This means that 8200 is probably the closest you're going to have whatever they had as there's not specifying.

It looks like for the rest your lubrication they do specify chronometer oil number one that's going to be hard to find I don't think it's made anymore. But they do reference that you could use Synt-A-Lube.

Then we've had discussions of automatic mainspring lubrication in the past. What always bothered me I remember reading something and I could never remember where? There may be other places but I found what I'm looking for in the document there's a test to tell if you did it right. I'm attaching that.

[AshF]

The watch ran for 37 hours on the bench so I'm going to chalk that up as a success.  The minute hand is really lose so I've got to address that before I can wear it and test it on the wrist.  So far I'm really happy.  What a beautiful movement but boy can you feel that bumper thud.

 

[arron]

Hey Guys,

I'm working on a Mido Multifort with a similar two piece mainspring as the OP.  I'm not wanting to buy anymore specialty oils at the moment.  Normally for mainsprings on pocket watches I've just used some 100% synthetic generic watch oil or my HP 9010.  Would it make a huge negative difference (even if not best practice) to use one of these instead of 8200?  I would be using it as suggested in the Omega watch repair manual linked above and by @AshF by putting it on the barrel wall and directly onto the mainspring.  It's a watch for my personal use only.  Thanks.  Arron.

[JohnR725]

44 minutes ago, arron said:

Mido Multifort with a similar two piece mainspring as the OP

in other words this is an automatic watch?

52 minutes ago, arron said:

Normally for mainsprings on pocket watches I've just used some 100% synthetic generic watch oil or my HP 9010.  Would it make a huge negative difference (even if not best practice) to use one of these instead of 8200?  I would be using it as suggested in the Omega watch repair manual linked above and by @AshF by putting it on the barrel wall and directly onto the mainspring.  It's a watch for my personal use only. 

it looks like you would like to use one of your oils or perhaps the 8200 on the barrel wall and the mainspring? 8200 perfect for use on mainsprings down below explains the purpose of breaking grease which the 8200 is not

On 4/10/2021 at 11:48 AM, JohnR725 said:

As this is an automatic watch special grease is required on the outer wall known as breaking grease. Breaking grease is designed to hold the mainspring in place until it's wound up far enough then it will break free function as a grease and release some of the power. Otherwise the mainspring wind up tight and the automatic will break. A special breaking grease is applied to the outer wall. Then as you're using an older spring you can use the 8200 lubricate that. It was a modern spring you wouldn't have to use any lubrication on the spring except the wall itself.

 

55 minutes ago, arron said:

It's a watch for my personal use only. 

in other words this is an experiment what's the consequence I suggest try it out see what happens probably shouldn't read the paragraph I quoted above which explains what breaking grease does as 8200 would have probably zero breaking qualities but for personal watch we can find out what's going to happen.

 

 

[Nucejoe]

 Have you checked the power reserve this spring delivers ? 

All old ones I have come across were SET.

[arron]

Thanks for the replies. Yes it is an automatic bumper watch. I know a little to nothing about automatic wrist watches so educated myself by reading a lot of your prior posts, which was very helpful. My understanding is that breaking grease is not required for this type with a two piece main spring.. Therefore I was hoping to get by with, either the generic watch oil or Mobius oil that I currently have. so I think I’ll just go ahead and give it a try doesn’t seem like there’s any permanent damage I can do. Ha ha. It would have been a good idea to check the power reserve before I disassembled it but unfortunately I did not.

[JohnR725]

51 minutes ago, arron said:

My understanding is that breaking grease is not required for this type with a two piece main spring.. Therefore I was hoping to get by with, either the generic watch oil or Mobius oil that I currently have. so I think I’ll just go ahead and give it a try doesn’t seem like there’s any permanent damage I can do. Ha ha. It would have been a good idea to check the power reserve before I disassembled it but unfortunately I did not.

the nice thing when you're learning watch repair with your own watch is that no harm comes if it doesn't work. so yes by all means try an experiment and no harm should come to it. his is where it's always fun to try experiments and go against whatever the rules are especially with lubrication because sometimes the Swiss don't get it right sometimes they do.