Using a Synrad 100W laser customized gaskets were easily created from a 6.5mm thick sheet of Ethylene-vinyl acetate (EVA) foam.

Ethylene-vinyl acetate (EVA) foam is used in a variety of industrial and consumer applications ranging from floatation vests to shoe insoles to gasketing applications. This flexible, closed-cell copolymer has excellent chemical resistance, good thermal insulation, and retains its flexibility even at subzero temperatures.

EVA foam cuts extremely well using a CO₂ laser, which is perfect for low-volume or custom applications where tooling for die cutting is too expensive. Non-contact laser cutting is also appropriate in high-volume manufacturing as it eliminates maintenance downtime resulting from cutter adjustment or replacement and product changeovers are simply a matter of loading a new cut file into the motion system.

This application involved cutting gaskets from a sheet of 0.256” (6.5 mm) thick EVA foam. A CAD file containing a full-scale drawing of the gasket drives the XY motion system, which in turn, controls a cutting head containing a 2.5-inch positive meniscus lens. Focused spot size is 0.004” with a 0.07” depth of focus. Using 100 watts of power and 10 PSI of air assist, each gasket is cut at a velocity of 275 inches per minute for an overall cycle time of 4.84 seconds per part.