I have a canon f1, the screw-in battery compartment cover is unfortunately jammed. It seems like someone tried to force the screw open, and botched it, and this has flattened the screw head for the cap. Whats the best way to get this open ? Thanks in advance ...
Take a Dremel tool and grind through the slot. Then, when you have a nice slot, insert a coin and give it a good turn. Use pliers on the coin if needed. Squirt some lighter fluid around the edge of the battery cover to loosen it up first.