Just like magic

The VM300 vacuum pallet changing system is simple and easy to use, with its ability to switch from pallet changer to vacuum chuck in seconds it effectively is two products in one.

Vacuum clamping systems are primarily used for holding wood, plastics, aluminium and other non-ferrous metals which require quick and simple machining. Compatible with CNC machines, vacuum clamping is cost-effective, increases productivity and minimises any clamping damage to the workpiece.

Vacuum clamping works on the basic principal of creation of a pressure differential between the vacuum clamping plate and the workpiece – the vacuum causes an ‘under pressure’ beneath the workpiece which presses the workpiece against the clamping plate. Thus the workpiece is not sucked but rather pressed against the vacuum table.

All objects are subject to atmospheric pressure of approximately one bar. When a vacuum is generated some of the air under a workpiece is removed, thus removing part of the pressure load on the workpiece surface. The net result is a one sided pressure on the top surface of the workpiece; the strength of which is dependent upon the size of the vacuum generated – generally 0.7 to 0.8 bar. This means that a vacuum of 200mbar (absolute pressure) is generated, and hence the pressure differential acting on the workpiece is 800mbar. The size of the clamping force is then only dependent on the clamping area.

The sliding force of the workpiece depends on its surface structure, the pressure differential generated by the vacuum and the workpiece area on which the vacuum acts. The larger the area, the better the holding force.

VacMagic VM300, the all in one pallet changer and vacuum chuck system, operates off 70psi shop air from a standard compressor; no special vacuum pump means no need for messy pump maintenance.

As an alternative to the magnetic chuck for non-magnetic materials, the VacMagic system is ideally suited for difficult to hold parts, parts too thin for traditional workholding, as well as soft or brittle materials such as graphite and plastics.

Hillcliff’s range of VacMagic products has been expanded to include the VM100 VacMagic system. With a smaller base plate surface area, it was primarily designed for grinding non-ferrous material on a magnetic chuck. Like its bigger brother, the VM300, it can be a pallet changer and vacuum chuck to enable reduced set-up times.

More recently Hillcliff has introduced the Multi-Power Vac, claimed to possibly be the most universal multi-functional vacuum workholding system currently available. With its 400mm by 350mm grid plate base, tapped with M6 threads and finely textured surface increasing holding force through friction, it offers high levels of flexibility for multiple workholding solutions.

Four vacuum ports within the grid plate enable clamping of either one large component or up to four smaller parts at any one time. Like Hillcliff’s other vacuum solutions the Multi-Power Vac operates off 70psi shop air from a standard shop compressor.

It can also be connected to other units to create even larger clamping areas; Hillcliff reports some customers connecting six units to create an area of 800 by 1,050mm.

Hillcliff Tools www.hillcliff-tools.com