Abstract: A brake for bending sheet metal includes upper and lower clamping members, with a pressure slideably mounted on the upper clamping member. A bell crank is advantageously provided with its longer arm being utilized as a handle. The bell crank is pivotally engaged with the upper clamping member and its shorter arm is coupled by a link to the pressure member. When the handle is rotated towards the clamping members, the toggle action of the linkage provides maximum force per unit rotation at the top of the stroke to securely lock the upper clamping member against the lower clamping member. A stop is utilized to prevent further movement of the handle once the link-shorter arm pivot point travels slightly past an imaginary line between the bell crank and the link-pressure member pivots. In one embodiment, the linkage is adjustable in length to regulate the amount of clamping force. The locking mechanism is coupled to the brake in such manner that it does not bridge the upper and lower clamping members.