subject: Magnetic Work Holding Allows Full Access to the Workpiece [print this page] Magnetic Work Holding Allows Full Access to the Workpiece
Magnetic work holding provides accessibility to up to five faces of a workpiece by removing the obstacles, interference and the constraints of mechanical clamps.
Most work holding methods involve many variations of mechanically securing a workpiece. But the mechanical clamping of workpieces can create obstacles to the machining process. Most importantly, mechanical clamps may not be conducive to some tasks that require complex operations such as 5-axis milling or even the simultaneous machining of multiple adjacent workpieces. Magnetic work holding overcomes the intrinsic problems of mechanical clamping.
Replacing Vises with Magnets
Mechanical work holders such as clamps, vises or other fixtures have been the standard bearers of work holding solutions for decades. But their common usage does not necessarily imply they do not have drawbacks. Non-even force distribution and part deformation are major deficiencies of mechanical clamps. Another is a lack of full support of the workpiece surface. For example, if toe clamps are used around the perimeter of a workpiece, there is no serviceable method for securing the center of a workpiece. As a result, the unsupported area can chatter, forcing a reduction in the speed of the cut, which increases cycle time. Magnetic work holding eliminates these deficiencies.
By replacing mechanical work holders with magnetic ones, the holding force is distributed uniformly over the entire workpiece surface without compressing or deforming the part. Since magnetic work holding secures the entire surface area of the workpiece, chatter and vibrations are effectively eliminated. In addition, this magnetic holding force is locked in without using the top surfaces of the workpiece as leverage for work holding and opens the way to unfettered, clamp-free operations. Magnetic work holding can reduce setup times compared to mechanical clamps.
Adding Accessibility with Magnetic Set Up Blocks
To increase the variety of machining operations suited to magnetic work holding, set up blocks or pole extenders can be integrated into the machine set up to increase accessibility. These blocks are essentially stand-offs that raise the workpiece above the surface of the magnetic chuck. This enables through-holes to be drilled without damaging the magnet. It also allows for side and back cutting as well.
