[Mcbride19]

I cut 5mm acrylic with 50w(not a real only 820mm long) with 2 pass at 90% power.
Take a look at your mirrors and lens(it may be dirty) it happens to me sometimes...

[Crafter]

You put a piece of acrylic on your bed with one end higher than the other the lower end should be below your normal focal point and the high end above. Draw a line and laser a cut on that line and see where it is the deepest and best cut. That will be your focal point make sure your laser head will clear the high end though.

err. im sorry . i dont really follow. is there any visual illustration for it anywhere ?

I cut 5mm acrylic with 50w(not a real only 820mm long) with 2 pass at 90% power.
Take a look at your mirrors and lens(it may be dirty) it happens to me sometimes...

its the same when its brand new, and even now with cleaned mirrors . still the same.

hi all
I think the problem is after all the mirrors and lens are clean that the airassist is a must. I cut with a old 40W tube ( over 1.700 hours on it) 6mm acryl with one pass at 85% power and 4 to 5mm speed, but only with air assist not the cone version, a version like epilog from the side . without air assist it would take more then 5 runs and the cut would look ugly not usefull.
greetings
waltfl

my machine do has air assist and its on the side.