Watch backs

    In our store we change watch batteries on a daily basis.  We
use the standard knifes sold in most jewelry catalogs.  Some watch
backs are extremely difficult  for me to pop off.  What do some of
you do to get off the really tough ones?

The standard knives supplied by the watch trade are not really sharp
enough to deal with many of the more modern watches, however, if you
change to the type of sharp, straight-edged blade I use you will
probably find inexperienced staff cutting themselves regularly!!

There are tools made commercially which have a blade in a screw-up
type of frame which will provide the wedging action under greater
control and are, therefore, safer for the operator. They are not,
however, as safe for the watch case as there is a temptation to just
keep tightening the screw until something pops! Much of the problem in
opening stubborn cases is related to the technique used. Find the
prising slot - either next to one of the case lugs or, more usually
nowadays, directly opposite the winder - hold the case firmly in the
hand, preferably in a cloth which will help to protect the hand if
the knife slips, insert a sharp knife blade and prise the back off
firmly by twisting the knife so that the sharp edge of the blade
comes up straight towards you. Don’t try to use the blade as a
screwdriver in the slot, it will only damage the watch back and wedge
itself out of the slot. If the back won’t come off, ask yourself
whether it is really a screw back in disguise! Before replacing the
back, you can probably help yourself or another jeweller in the
future by filing the prising notch a bit deeper - some are almost non
existent nowadays when the watch is new.

I assume you are thoroughly cleaning around the case back before
trying to remove it so that there is no loose debris there which can
fall into the movement and that you replace any rubber or plastic
seals as a matter of course to maintian water resistance…

Best wishes,
watch restorer
Ian W. Wright LBHI
Sheffield, UK