Today a friend asked me a question that the folks at Stanley tell me they hear all the time: why does the claw — you know, the little catch at the end of your short tape measure — move back and forth? Is it just poorly attached? The short answer: no, the loose claw is no accident of manufacture. It’s loose on purpose. The longer answer lies after the jump.
Actually, the claw moves back and forth slightly to allow you to measure both the length of an item inside the claw and an item outside the claw. To do this, the claw must slide back and forth by a small amount — exactly the same distance as the width of the claw. That way when you, for example, push the end of the measure against a wall, the claw slides in and renders an accurate measurement to the wall. When you catch the claw on the end of a stud and pull to measure a cut, the claw slides out and again you get an accurate measurement to the end of the board.
And if the claw is firmly attached and doesn’t move? Better check to see whether the tape’s calibrated inside or outside the claw before you measure or you could end up with an extra (or worse short a) 1/16″ or so.