[billybop]

When replacing a screw in case back I'm confused as to if the case back threads and the gasket or rubber O ring should have a light coating of oil such as stem lube.
My watch maker does very good work but never lubes the threads.
It just seems to me that to lightly lube the threads will allow the back to screw in much easier. And a light coating on the rubber O ring would create a better seal.
So, what do you think?

 

[CometHunter]

I'd say leave the oil alone! Skim-reading the automotive sites, I found a few controversies about whether or not oil affects rubber. If it's possible with tires, it could be possible with certain watch gaskets and o-rings. And all the watches that I've had serviced come back with dry rings. That's good enough for me! My watchguy knows more about this stuff than I do.

As for the case back: you DO NOT want it to easily unscrew. That's asking for trouble (ex: moisture permeation). All you need to do is make sure both sets of threads are clean and dry.

The bottom line is if it's not broke don't try to fix it.

 

[9pm]

No, don't oil the screw thread!
As for the gasket don't use oil. They use silicon for better waterproofing.

This is the instruction from the mov't maker, ETA.

 

[ulackfocus]

No, don't oil the screw thread!
As for the gasket don't use oil. They use silicon for better waterproofing.

Bingo! There's a round plastic case that has a sponge-like top and bottom inside that I've seen Sam use. The spongy things have the gasket lube in them, and you place the gasket on top of one, close the case, and twist the lid so the gasket gets coated easily. Plus, it's a little slick so the gasket doesn't grab on the caseback when it's twisted down.

 

[Presa canary]

All depends on how long you've been together my friend....