Polycarbonate sheets

[Gary Noble 6363]

Hi,
I have a 60w laser machine and am having big problems cutting out holes in hollow double wall 4mm polycarbonate that has been uv coated.
The problem I am having is that the fumes seem to be going down the flute and scorching the material.
Is it possible to laser cut/engrave this material? if so what would the settings be?

Thanks in advance

Gary

[Gary Hair]

Are you using air assist and do you have your blower on? Is the material raised off the laser bed on a honeycomb or pins? If no to any of those questions then I would start there and see what happens.

Gary

[Martin Boekers]

Polycarbonates are nasty to cut, yes you can cut it, fumes aren't good and usually gives a nasty yellowed edge.
Not as nice as acrylic.

[Richard Rumancik]

Gary, polycarbonate will not cut very well with a laser at the best of times - I have cut .030" film successfully (it leaves a golden colored edge) but beyond that you will get rough, black, carbonized edges. It creates a lot of green smoke when cut; if that smoke gets inside the flutes you probably will not be able to do anything about it. Quite honestly I don't think the laser is the best option for this hollow polycarbonate. Waterjet might be a better alternative or possibly a CNC router.

[Joe Pelonio]

I get yellow smoke, not green, but it's nasty. I stick to 1/8" or less on polycarbonate and charge extra for it. The problem with anything fluted is that you have to set the speed/power to cut through the bottom and it's too much for the middle. Coroplast/corex up to 4mm seems to do OK but what you are trying to cut (I use it on my greenhouse) is better left to other methods than laser.

[Gary Noble 6363]

Many thanks for all of the replies.
It was the yellowing that was of most concern.
I think from now on polycarbonate will go to the top of my list for things to avoid.

Once again thanks for all of the advice.

Gary