Hi, I'm embarassed to admit that my father was a watch and clock maker/repairer all his life and that I never followed in his footsteps or paid much attention to his work, although I seem to recall that he used the equivelant of a pen knife to open the backs of watches where there was no obvious place to insert anything. I think the principle is that the knife blade was thin but sturdy and had a keen edge so that the cutting edge could get in between the rear casing and the main front part of the watch ( there should be a clearly visible line around the circumference of the watch dividing the back from the front) then gentle pressure was applied together with a bit of levering ---- it didn't seem to matter if the watch was square or circular in design and afterwards it was just reapplied by hand pressure and sometimes had a sort of snapping shut sound. This can not be done to any watch that is generally waterproof to 100 metres and more, should this apply to yours.
Hope of some help.
Kevin
kevin mckeever, August 2008
