Problem cutting lexan

[brian257]

I was trying to cut some 1/8" lexan (polycarbonate) on my 40W laser today and I am getting very bad results. The laser is only getting about 2/3 of the way through and is leaving a lot of burning on the surface. I have tried fast and slow speeds and high and low power settings. I have tried with a lot of air assist and with a little, but nothing is satisfactory. Is there something going on with my laser or is the problem that I am using lexan instead of acrylic?

[Axeman]

Lexan usually needs a considerable amount of power (not to mention that it gives off chlorine gas when cut unless you have some stuff that was specifically made without chlorides).

Lexan won't give a nice cut unless it has very high power anyway (regardless of it's toxic effects). Just avoid it altogether.

[brian257]

Thanks Axe. did some more searching online and as you said, lexan does not cut well at all. Bought some acrylic and that cuts like a hot laser through butter with a beautiful edge. Hmmm, custom cut butter pats in heart shape with initials for wedding dinners....

[Axeman]

There has been talk, since I haven't actually done it...that if you take a blowtorch quickly to the cut edge of your acrylic it will re-firm it back up and polish the edges.

Apparently the laser cut edge makes it quite brittle and it needs a bit of annealing. Just some food for thought.

[brian257]

I have done that before to saw cut plastic, but not sure if it was acrylic or lexan.

[scrappyjedi]

I've had the same issues cutting Lexan, and I eventually gave up and switched to plain acrylic instead. No issues there!