Laser cutting polypropylene


I wonder if anyone has tips on laser cutting polypropylene? My experience has been that using the same settings I use for acrylic (100% speed at full power -- 30-35 watts) it takes tens of passes and makes jagged cuts.


I'm going to follow up on my own post for the benefit of anybody researching this question later.

I experimented with some cuts last night on HacDC's Full Spectrum Laser 20x12. My hypothesis was that at full power, the laser was melting the plastic so much that it was welding back together plastic it had cut during previous passes. I tried a variety of lower power settings with many passes and lower power settings at slower speeds. Ultimately I settled on 25% speed, 75% power, and 5 passes. It's not perfect -- there's some puckering of plastic around the cuts -- but it made clean cuts and didn't take all day (33 minutes for the shell). If I were doing it again, I might do 6 passes, at least for the large outline, which was a little jagged but sanded down nicely.


Hi Rob:

Your post really caught my interest.

Im trying with a different "hull" design where building material is a key factor.

For a reasonable evaluation, provided that laser cutting seems to be the standard parts construction system for this project, the information you've posted is quite interesting.

I built this "normalized" table, where all factors taken into account are relative to unity. Hence an evaluation equation can be used for material choice, which result is given in the last column.

(Second column "Compared value") relates to price.

But, as you can see, the cutting factor is not included. Only from variables above, Polypropylene results to be the more suitable material, followed by Polyethylene.

This second one, has severe problems for glue choice, but could be solved.

Do you have any information about Polyethilene laser cutting ?

Regards and thanks for your information.



Made a video about polypropylene laser cutting as I only found different opions on how you can cut polyproplene with a lower power, cheaper laser cutter like the K40.

Hope you find my results worthwhile and use it for your own projects.