Longines 506 No open spring barrel

[Jakub]

Hi there!

Yesterday I started tear down of Longines cal. 506. Nice movement, but found this main spring barrel that has note “Do not open”. 
I am no experienced watchmaker and so I maybe should follow such a instructions, but I’m also curious. 
My question is, is there way how to open and then safely close barrel of this kind? What is potential dangers, if yes?

If not, how to service such a part without opening?

Regards 

Jakub

[Poljot]

1 hour ago, Jakub said:

Hi there!

Yesterday I started tear down of Longines cal. 506. Nice movement, but found this main spring barrel that has note “Do not open”. 
I am no experienced watchmaker and so I maybe should follow such a instructions, but I’m also curious. 
My question is, is there way how to open and then safely close barrel of this kind? What is potential dangers, if yes?

If not, how to service such a part without opening?

Regards 

Jakub

Of course you can open it simply by pushing the arbour and placing the barrel on a holder or tweezers.

 

[Nucejoe]

If it feels like you may deform the lid or barrel !   don't open it.  

 

[Poljot]

I say, cover that note with Post-it sticker and open it! Be a man!

Open it without any fear or fanaticism also - if you push it to far, the mainspring can snap near barrel.

https://www.aliexpress.com/i/4000214918799.html

 

[watchweasol]

I think the theory behind sealed barrels is the fact that the parts, barrel and spring take quite a lot of stress during operation so therefor if you need to change the spring then also change the barrel. This in effect eliminates any problems just putting a good spring in a worn barrel and it is a one step operation. Not only that you have to buy the barrel and spring (greater cost). The barrel can be opened as poljot says and done carefully would probably be ok, but bear in mind some of the longines barrels were greaseless and greasing them lowers the power reserve due to  excess slippage.  so in effect you take the chance.

[nickelsilver]

The link to the other thread above is about a Zodiac barrel, which you very definitely don't want to open unless you want to search for another- or make a new cap. As I recall the Longines "do not open" can indeed be opened, it's been a while since I did one but I think the cap fits "over" the barrel, like a 7750 cap, and it's good to lift it off starting with a thin blade working around the rim. If you just push the arbor the cap has a tendency to actually grip harder as it bows.

[Jakub]

Big thanks to everyone who chipped in, big help indeed. 

Alright I hear you all. Now after reading the thread posted above (thank you @Poljot) and all other posts. I came to conclusion and this is what I going to do...

Clean the rest of the watch and barrel exterior will get “peg & rodico treatment” and arbor D5 in place where it meets barrel. After assembly put it on timegrapher and see what’s up. I guess mainly focusIng on amplitude. 

The movement is clean, no oil paddles and no service marks. Barrel itself is nice and clean, no old oil black stains. So I will hope this works. If don’t I gonna get down to open it up. 

Tomorrow I’ll get to assembly, and will let you know how did it worked out.

I feel like posting a picture of watch in parts

Cheers!

[Jakub]

Good evening guys!

So after work right behind watchmaking desk. I did exactly as I sad. Once I’ve put it together and tiny tweak, here is result from all mighty Weishi No 1000. Think I leave it that way.

One more time thanks for all inputs.

Cheers