Abstract: A reciprocating saw, such as a compass (jigsaw) saw or similar saw, has a blade clamp for securely clamping blades having different dimensions. The clamp has a blade seat with bearing surfaces for at least two adjacent, axially extending surfaces of the saw blade shank, and a stop surface for the rear end of the blade shank. A hand-operable clamping element is mounted on the blade seat and is pivotal about an axis between a releasing position and a clamping position. A spiral clamping surface is formed on the clamping element and has a constant opening angle. Through the use of a spiral clamping element with a constant opening angle, the clamping element maintains the same clamping angle with saw blade shanks of varying dimensions.