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Main Spring Question


bjd1020

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I have a barrel for a 7750. After building up the movement it seems as though the main spring is "slipping". When I wind the watch I can feel the spring tension build the I get a click and the tension releases. I opened the barrel and had a look and to my novice eye things look fine. Normally I just buy a new barrel as they are relatively cheap. I have watched a few videos on spring replacement. Is this normal? Did something just come loose? The arber inside the spring looks like it just has a catch that when its turned it catchs the spring. Im guessing this is designed to slip to prevent overwinding however its slipping after two turns of the stem. Anyway. If anybody has any insight id appreciate it. Thanks.

 

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No you can't use Moebius 8300 for the barrel wall. The recommended braking grease to use for ETA 775 is Kluber 125P, which is expensive. I have used Moebius 8213 for Omega, and if the barrel is aluminum, then use 8212-SC for moderate braking. The mainspring on the 7750 is quite stiff and thus needs a strong braking grease.

 

http://www.moebius-lubricants.ch/en/products/greases

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Man its a lot to learn. Just when I think Ive got ot down a whole other segment of learning appears. These movements are like machines built with multiple little machines. Thanks for the input.

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1 minute ago, bjd1020 said:

Man its a lot to learn. Just when I think Ive got ot down a whole other segment of learning appears. These movements are like machines built with multiple little machines. Thanks for the input.

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You're welcomed. If you need a little braking grease to finish this project, I can send you a few cc's in a zip baggie and mail it to you. PM me with your address.

J

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You're welcomed. If you need a little braking grease to finish this project, I can send you a few cc's in a zip baggie and mail it to you. PM me with your address.
J
That is very kind of you to offer. Ive spent a lot on lubes lately. There are awesome people in this world after all. Thanks for reminding me of that. If you only knew. Lol.

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1 hour ago, bjd1020 said:

That is very kind of you to offer. Ive spent a lot on lubes lately. There are awesome people in this world after all. Thanks for reminding me of that. If you only knew. Lol.

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My pleasure.

J

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