Here are some tips & techniques anytime similar situations presented themselves:
- Have a screwdriver tip that fits snug and goes all the way down in. Proper tip fit is essential and will determine sucess or failure. You might even have to file an existing screwdriver tip to get the right fit.
- Placing the device on a surface that offers sufficient resistance to downward force but still protects the device, place the palm of your non-dominant hand on the heel (back end) of the screwdriver while using your dominant hand to turn the screwdriver in the proper direction (righty tightey, lefty loosey). The non-dominant hand provides downward force only. The dominant hand provides torque only.
- If needed, a pair of vice grips clamped securely to the shaft of the screwdriver to give more leverage. (This will likely scratch up the shaft of the screwdriver)
- The key is the split second the screwdriver begins to come up out of the screw slot, you are stripping the head. You must stop torque before the tip comes up.
- If the tip comes up, you are not supplying enough downward force with the non-dominant hand.
- Sometimes it helps to slightly turn the screw tighter (only slightly) then try loosening.
- Do not focus on one screw. If there are others that attach the same piece, try another one. All will not be as tight and if you get one loose, the extra flex will help the other(s) to loosen.
- If you get really desperate, you might try a drill bit with the drill on reverse and applied slowly. *** THis is a last ditch effort and has serious potential to cause damage and WILL destroy the screwhead***
- You can also (if there is room), make a slot in the screw head with a small file if it is chewed beyond use. This is also a last ditch effort.
I have not, to this day, found an electronic device screw I could not remove with these methods (or the unmentioned method of using a dremel tool to slot the screw if there is room).
YMMV, use common sense, if something gets messed up, please do not blame me.
Hope this helps.