I bought this one several months ago. It did not run and I could not get the back off and whoever tried before me, chewed it up quite a bit. I sent it to two watchmakers and neither could get the back off even after using penetrating oil.
I got it back and was willing to try the "glue the nut to the back" trick. I decided to go with washers instead to give me more surface area to glue.
I used super glue and let it set overnight just to be sure.
I set the watch in my wooden case vise and then then to the bench vise. I gripped the washers with a pair of slip joint pliers and twisted pretty hard. At first the wooden vise gave way, so I had to chisel out a deeper grove so it would sit tight in the vise.
I twisted real hard again and low and behold, the case back started unscrewing.
The bumper movement has a little rust on it, but the balance seemed good. I'm sending it back to one of the watchmakers who will try and service it. Fingers crossed that he doesn't
need parts because that will be tough. (Unless someone here knows of a source?)
It's a rare watch that I would like to see running. It's stainless with a solid yellow gold overlay on the bezel and tops of the lugs, but not all watches can be saved.
Anyway, more to come. Oh yea, I got the washers off by soaking the case back and washers in acetone overnight.