How To Get My Caseback Open

[Danny]

I thought I read a while ago, probably on here, that with the Swiss ETA movements, you can open the caseback and adjust a small screw in the movement to compensate for lost/gained seconds. My watch is gaining about six seconds every 24 hours, and I'd really like to adjust it, but I don't have a clue how to get the back off. I tried twisting with my bare fingers with all my might (which isn't much) and it didn't seem to budge. I haven't gone anywhere near it with any sharp objects because I want to make sure I know how it comes off before I go poking around with something that could damage it. Here's a picture of the back:

If it pops off, where exactly should I slide the razorblade in to create a gap?

[ubiquitous]

Leave your watch alone... It's +6 sec/24 hours, which is pretty good for a mechanical movement. Besides... If you can't even figure out how to remove the caseback, what makes you think you can adjust/improve your watch's time keeping ability?

My advice... Leave it be.

[Pugwash]

If it pops off, where exactly should I slide the razorblade in to create a gap?

Eek!

You need specialist tools: It screws off. Like Ubi said, it's close enough.