decasing a movement from a STB watch

[Gaus]

Dear watchfriends,

 

I have a STB watch (1970-1979) from a friend for repair. The problem is that I can't find out how to decase the movement (eta 2783). I am almost sure that it has to be removed from the crystal side (see pictures caseback side), but I can't figure out how. There are no lips (for caseknife). Possibly the bezel is screwed. 

I included some pictures. I looks like there is a lip, but it is no lip.

Thank you in advance for your help.

Kind regards,

 

Hans

 

[jdm]

2 minutes ago, Gaus said:

Possibly the bezel is screwed. 

Not screwed but you may need to use a bezel tools. Some are discussed in topic below: