Main spring barell replacement

[jurc1973]

Hello

I would like some advice.

I m starting to learn watch servicing,so i serviced seiko 7009 movement.

At the time i didnt service main spring because i thought beter leave  it as it is.

But now the watch has low amplitude...160°

So my question is :

can I remove the wheel train bridge , leave the center wheel atachet with the center bridge on one side and cannon pinion on the other and leave the day date side as it is to get to the barel.

thanks for help

 

 

[RichardHarris123]

Hello and welcome.  I  haven't worked on that model so I don't know but someone will advise you. 

[oldhippy]

I don't advise playing about like that, you are going to disturb the oils. Treat it as a new repair. Many years ago we would replace the complete barrel unit Seiko I think said every 7 years, because the shortage of parts and also they are obsolete it is normal practice to open the barrel remove the spring and clean it just like you would with any watch barrel. If the spring is tired and out of shape then replace it with new.  

[jurc1973]

You are probably right about the oils, i am obviously looking for a shortcut, since  i already done the job twice...after the first time it felt on the flor, broke the main plate jewel and center wheel....after that replaced dameged parts...now im not satisfied with amplitude...its just that am learning...this oldie kinda wants to get on my wrist

Foto of the watch and spare spring

[clockboy]

Many pro repairers just replace the mainspring with new as part of the service price.

[jurc1973]

Hello

Just to let you know....i took it apart ,oiled,serviced mainspring and im happy with the result.

Got about 100° better amp.

[JohnR725]

On 11/11/2023 at 12:31 AM, jurc1973 said:

oils

Mainsprings and lubrication are interesting. Depending upon whose service information you look at and depending upon the type of watch. So for instance if you look at modern mainspring this do they need to be lubricated at all? If you go to a modern school and ask the instructor why are we being taught how to lubricate mainsprings when they don't need to be lubricated quite honest I really don't remember the answer to that question but in schools are taught the lubricate mainsprings.

Omega has an interesting document on recycling mainspring barrels. Interesting because in their service centers they just replace the whole thing because they have an endless supply of them. But in the case of recycling the mainspring is just wiped off with a lint free cloth no lubrication.

For instance there is an image of a lecture I once gave where I had a whole bunch of packages of mainsprings a few of them actually do say permanent layer self lubricating no explaining as to how or why. Others don't say it all and notice that at least all the modern ones are guaranteed for life and they never break which is interesting because they do break and they don't last forever. But the companies are no longer around to honor the warranties so life of the company

 

One of the problems with a mainspring barrel is its typically sealed. Sell you can look at it and ignore it because you can't see the contents. If it really was not lubricated with anything like a lot of them are you might actually be fine to leave them alone. But if they been lubricated the lubrication can go bad with time and get sticky as you found out. Plus Accorsi of the barrel arbor which needs to be lubricated. Then in the case of anything that's a vintage blued steel it's probably sent.

On 11/11/2023 at 1:09 AM, clockboy said:

Many pro repairers just replace the mainspring with new as part of the service price.

In the shop that I were The prior watchmakers wouldn't even think of touching a watch without a replacement mainspring. The current watchmakers will do a variety of things and I try not to pay attention to what they're doing. I do kind of like Omega's approach of looking at the spring and seeing if it looks like it's still usable it looks like it's still going to work and of course when you put her in the watch it does seem to work than it is probably fine. Even on vintage pocket watches what I take the spring out of its white it looks right and the watch seems to work right I will use the old spring.

 

[Waggy]

Hi there, sorry I'm late to the party, I have done a few 7009s and always take the mainspring out and give it a clean. like @JohnR725 says, the philosophy of changing a mainspring varies. However, I think just blanket changing it regardless of its condition is wasteful and an unnecessary cost to you or your customer. I look at the condition after cleaning and if in doubt I change it, otherwise if it is in good shape I will re-use, which I think is what most of the guys do here. Seikos use the thick black graphite grease in the mainspring barrels which looks a lot worse than it is, the springs can be difficult to reinstall without kinking (due to the reverse bridal) and sometimes jump out, due to the shallow barrel, but once a good spring is reinstalled they seem to perform well even with swiss oils lubricants.