Lock for power tool

A saw, comprising:

• a saw blade extending from the saw;
• a sliding member slidably received in the saw;
• a support;
• a biasing member;
• and
• a pair of lock plates, and
• a shoe for bearing against a workpiece, the shoe extending from the saw and mounted to the sliding member,
• first ends of each of the lock plates being pivotably attached to the support at a first side of the sliding member, and second ends of each of the lock plates being biased toward one another at an opposite side of the sliding member,
• each of the lock plates being biased by the biasing member such that a first contact portion of the lock plate contacts a first surface of the sliding member at the first side of the sliding member, and a second contact portion of the lock plate contacts a second surface of the sliding member at the opposite side of the sliding member, wherein the sliding member is secured with respect to the support.