Quote Originally Posted by dr bob
Cleaning must be done carefully however. A little fine (250 or greater) sandpaper (no emory, please) and hold the solvents. A little Vaseline will protect contacts for a longer time after cleaning.
One thought about cleaning contacts: A *clean* pencil eraser works well - just about the right abrasive quality - and being on the end of a pencil, allows it to be used in some fairly deep battery compartments. Use compressed air to blow away any dust remaining.