A hold-down clamping apparatus comprising a hold-down clamp with body having a top lip and pair of guide legs disposed between a central screw in the body and a support having holes in vertical alignment with the legs and the screw for securing and holding down a sheet material for processing. The screw is threaded through the support screw hole as the legs are inserted within support holes until the top lips contacts the sheet material to hold down the material and to prevent twisting of the hold-down clamp. Supports with clamps may be fastened to tools or supports. In one embodiment, the support has a grid of holes for securing a plurality of materials with hold-down clamps. In another embodiment, the hold-down clamp comprises a top lip and a guide beam slotted in a support and secured.

An embodiment of a vise may include a clamping structure having a first clamping jaw, a second clamping jaw positioned relative to the first clamping jaw, and a quick adjust jaw guide to maintain the first clamping jaw relative to the second clamping jaw. The quick adjust jaw guide may include a driving element to apply a force to move the first clamping jaw relative to the second clamping jaw, wherein the driving element comprises a release structure to release the applied force to facilitate rapid adjustment of the first clamping jaw relative to the second clamping jaw.

A vise including a body, a threaded shaft extending through or positioned adjacent to the body, and a block coupled to the body and spaced away from an axial end of the shaft. The vise further includes a pair of carriages carried on the shaft and configured such that rotation of the shaft about a central axis thereof causes each carriage to move axially along the shaft. The vise also includes a pair of clamps releasably coupled to the shaft and positioned adjacent to the block on opposite sides thereof. Each clamp is adjustable axially along the shaft to enable adjustment of an axial position of the shaft relative to the block.

A clamp release mechanism is provided. The clamp includes a body, a shaft slideably coupled to the body, a fixed jaw, and a moveable jaw coupled to the shaft. A locking component actuates between a locked position and an unlocked position. When in the locked position, the locking component biases the shaft to remain stationary with respect to the body. The clamp includes a securing component pivotally coupled to the locking component, and a biasing element that biases the securing components towards the shaft.