Small lip when cutting acrylic

[Eric Fuller]

Been cutting more acrylic lately (usually I cut wood) and I'm noticing that there is always a small lip on both sides protruding above the surface. It feels very crisp and sharp.

Everything I've cut so far has been extruded if that makes a difference. I'm working on a design which will require sandwiching several layers and gluing them up...but because of the lip the surfaces don't make very good contact. No way I can deburr all the pieces before I glue, so I really need to solve this.

Anyone know how to avoid this? Laser is 80W and I always use air assist when I cut.

[David Fairfield]

Can't say I've experienced the same with acrylic but lowering the frequency way down helped solve that problem for styrene.

Dave

[Frank Corker]

Eric the raised edge is too much heat. Reduce the power or increase the speed should stop that happening.

[Stephen Beckham]

Concur with Frank...

Take a piece of scrap and cut some straight lines about one inch long. Cut one at your normal speed, move over a bit and cut another a bit faster and so forth. Keep doing it until you notice you're not getting through the plastic or the lip is gone. Don't take the lines past the edge of the plastic - by keeping them in the center of the scrap, you'll also be able to see where your biggest problem will occur at start/stop points, or sharp angles when the laser will sometimes over heat an area.

[Eric Fuller]

Excellent...I'll give that a shot guys. Thanks!