Its about TIME someone answered your question. 20060221160907 MET.
I have just taken my own casio battery watch apart. Using a sharp knife, the back plate can easily be removed, if you are good with your fingers. Then the battery can be removed/changed. My hands had fallen off and so I had to remove the movement from the body. I had seen a street vendor do this in Africa last year and working from plastic bags and with most sophisticated device being the screw-driver I realised that I could do this myself. So, today I have been able to repair another watch left in the washing machine, - back removed, the watch set to dry sowly on a radiator and I have just replaced the battery and it is still going four hours later. Now with the movement, it is necessary to remove the winder. (Being a layman I will use words which occurr to me, the Horological Institute in UK have got a website where I expected to see lots of good tips but there was nothing, from the look of it dead since 1999!). OK, on some watches the winder can just be pulled out and will then release the movement. On my Casio (Ten years old, good in its day battery driver analogue and digital in one) there was a "push" statement somewhere on the "plate" or green circuit board. I saw a metal lever, which on pressing with a very small screwdriver could be moved back and forward. Since the winder did not let itself be removed with a fair amount of force, I realised that perhaps this lever would need to be pressed first. I did so and nothing happened. Then I saw that as the lever moved another part moved too. This other internal part I then pressed with a strong needle and there was a click and I was able to remove the winder. Then the body or movement was able to be removed - a lot of fiddling around with a good lamp and also a small microscope (25x magnification) helped me to be able to see that all three hands could be placed back on their "axels". They are now all in position and I am able to put the movement back in place and unfortunately the winder when inserted does not click lock in position. There is something which any watchmaker will know about how to get the lever to return to its original position so that it can grab the winder and hold it in place.
At least you have now got your watch apart like me now and can sit and wait a year or two until some decent watchmaker turns up and gives us both some more advice. If it was a computer there would be no end of advice and tips but watch-makers have to protect their professions and so will not give any advice ruining the chance of losing trade.
Thus the watch trade died. If they don't give anything out - they don't get anything back - the law of physics/feng shui/karma
20060221162719
That didn't take long.
Kenneth Keen, February 2006