Piston Jaw Holds Multiple Parts in Standard Machine Vises
Up until now, the ability to use standard machine vises to securely hold multiple parts for increased machining production has been limited to designed costly dedicated fixturing. This costlier solution sacrifices flexibility, versatility, and ultimately profitability.

Snap Jaws Manufacturing (Troy, MI) has introduced its new Piston Jaw vise jaw to provide solution for multiple part holding requirements. It uses a patent-pending design that applies the physics of hydraulics through a series of internal passages and O-ring sealed pistons to provide rigid holding of up to five parts at a time for multiple part machining.
The key element of this jaw design is its ability to hold similar parts with different outside dimensions (up to 0.025 in.) with equal and adequate holding force. The Piston Jaw is designed to be used with a standard 6 in. milling vise, so part size limits the number of parts that can be held in one setup.

The basic design of the jaw features two rows of clamping pistons built into a 2-in. wide by 6-in. long self-contained sealed steel housing. The housing is machined with internal hydraulic oil passages positioned behind the pistons to provide the consistent and uniform clamping pressure. There are five pistons in each row spaced at a centerlinedistance of 0.750 in. above and below each other. Side-to-side centerline spacing is 1.200 in.
Secondary oil passages connect the first chamber in the top row with a second chamber in the bottom row so the flow of hydraulic fluid between the rows is proportionally restricted to provide uniform holding force. The pistons independently compensate with the hydraulic fluid pressure equalizing and balancing the force for each piston. The assembly also uses a pin, inserted through the housing and slots in each upper and lower pair of pistons, to prevent mechanically the pistons from being forced out of the housing when clamping pressure is applied to the other pistons.

The Piston Jaw can be used with a matching V-jaw to hold one to five parts, ranging from 3/8 to 1 3/16 in. diameter or three parts up to 2 in. diameter using every other V position. With machined soft jaws, even hex, rectangular or irregularly shaped parts can be securely held.
The Piston Jaw features the popular Snap Jaw quick-change vise design and is available with a variety of interchangeable piston tips that include steel, aluminum, brass, carbide, serrations, stainless steel. Nylon, or machinable steel. A special swivel tip is also available.
Snap Jaws Manufacturing, 33215 Dequindre, Troy, MI 48083; phone: 248-588-1099