Laser cutting plastic less than .1" thick

[Todd Mueller]

I am going to be a new chinese laser owner and have a pretty good idea of laser usage from watching about 10 million videos, but i believe my machine will come with a honeycomb bed and i will be cutting some pretty intricate designs in plastic that is less than .1" thick. The designs will have areas of material that get as narrow as .5mm or so that will stay attached to the main work. there will be other areas that are cut that are meant to drop out once the cutting is complete.

to be clear, think of a christmas tree shape and cutting out small holes for lights, xmas bulbs, tinsel strands etc. or maybe long thin narrow leaves that will just be dangling off the work and only attached on one end like where it attaches to a branch.

will the air pressure form the machine air compressor or anything cause my material to move around making it necessary to find a way to do any type of hold down or should i be good to go? I have never owned a laser so i have no idea if plastic material between .06 and .1" will be heavy enough to stay put on its own during the process or not?

would i be better off making a raised pin bed of some sort to do my cutting on or just use the honeycomb, some of the stuff i want to cut would be so intricate that you would have to have a ton of pins to make enough support for some of the small pieces, so honeycomb seems like it would be sufficient to me at this point

im thinking guessing at this point around 50 watts at 15mm/sec might be a good starting point.

[Bert Kemp]

you didn't say what your laser is how many watt tube ect . Your talking very thin like paper thickness? is the plastic rigid or very flexible? I cut thin paper at about 10% pwr and 60 mmps.
if its rigid magnets might work to hold it down
being so thin I would be tempted to turn air off but not sure if you'd get flare ups. You'll need to experiment


I am going to be a new chinese laser owner and have a pretty good idea of laser usage from watching about 10 million videos, but i believe my machine will come with a honeycomb bed and i will be cutting some pretty intricate designs in plastic that is less than .1" thick. The designs will have areas of material that get as narrow as .5mm or so that will stay attached to the main work. there will be other areas that are cut that are meant to drop out once the cutting is complete.

to be clear, think of a christmas tree shape and cutting out small holes for lights, xmas bulbs, tinsel strands etc. or maybe long thin narrow leaves that will just be dangling off the work and only attached on one end like where it attaches to a branch.

will the air pressure form the machine air compressor or anything cause my material to move around making it necessary to find a way to do any type of hold down or should i be good to go? I have never owned a laser so i have no idea if plastic material between .06 and .1" will be heavy enough to stay put on its own during the process or not?

would i be better off making a raised pin bed of some sort to do my cutting on or just use the honeycomb, some of the stuff i want to cut would be so intricate that you would have to have a ton of pins to make enough support for some of the small pieces, so honeycomb seems like it would be sufficient to me at this point

im thinking guessing at this point around 50 watts at 15mm/sec might be a good starting point.

[Todd Mueller]

you didn't say what your laser is how many watt tube ect . Your talking very thin like paper thickness? is the plastic rigid or very flexible? I cut thin paper at about 10% pwr and 60 mmps.
if its rigid magnets might work to hold it down
being so thin I would be tempted to turn air off but not sure if you'd get flare ups. You'll need to experiment

It is a 60 watt machine, and thinking about 50 watts to cut at, probably around 60 to 65% power, due to going higher doesn't seem to gain many more watts from most of the information i have found.

but anyway, no not paper thin, if you have a micrometer i guess you could determine how thick between .06 and .1" is, not sure how else to explain it besides the exact measurement. It's pretty rigid, considering how thin it is, certainly not like paper, if you cut a small piece that is only .8mm wide or so, it would easily snap off if you tried to bend it very far.

magnets if strong enough could possibly work as a hold down, but since my machine is still in customs and i dont have it, i dont even know if the honeycomb is magnetic itself?

turning off the air seems like a bad idea due to smoke/debris getting onto your lens/mirrors?

maybe think 1/2 as thick as a rubber key chain, like the one that might be on a motorcycle key chain, or as thick as a cr2025 button cell battery like the one that would go in a garage door opener, or a little thicker than the sidewall of a tupperware container.

it is a co2 sealed laser tube

[Lee DeRaud]

I cut intricate shapes in 0.092" acrylic all the time on a honeycomb bed, no problem. Doing the same thing using 1/43" veneer, I'll usually tape it to a sacrificial piece of MDF.
Take that for what it's worth.

[Dave Stevens-Vegas]

The honeycomb tables are typically aluminum. You are likely to have more turbulence from the exhaust than the air assist. When I've cut plastics that thin I've been under 20% power on an 80 watt laser, depending on that material. If it moves you can hold it down with tape or using something weighted in each corner. Just make sure if you use something on the cutting bed your pathing doesn't smack the lens assembly into what you are using to hold.

I wouldn't turn off the air assist. The primary role of air assist is to prevent or at least minimize a flareup. It's easy to roast plastic that thin.

Dave
roaddoglabs.io

[Bert Kemp]

You can turn off the air if you have good fume extraction. If your honeycomb is not magnetic you can make a magnetic grid table pretty easy. Theres an on going thread about this right now a few threads down. if its a true 60 watt tube ( 1200mm in length 54 mm Dia. ) you won't need 65% pwr to cut it .


It is a 60 watt machine, and thinking about 50 watts to cut at, probably around 60 to 65% power, due to going higher doesn't seem to gain many more watts from most of the information i have found.

but anyway, no not paper thin, if you have a micrometer i guess you could determine how thick between .06 and .1" is, not sure how else to explain it besides the exact measurement. It's pretty rigid, considering how thin it is, certainly not like paper, if you cut a small piece that is only .8mm wide or so, it would easily snap off if you tried to bend it very far.

magnets if strong enough could possibly work as a hold down, but since my machine is still in customs and i dont have it, i dont even know if the honeycomb is magnetic itself?

turning off the air seems like a bad idea due to smoke/debris getting onto your lens/mirrors?

maybe think 1/2 as thick as a rubber key chain, like the one that might be on a motorcycle key chain, or as thick as a cr2025 button cell battery like the one that would go in a garage door opener, or a little thicker than the sidewall of a tupperware container.

it is a co2 sealed laser tube

[Mike Null]

With the thickness you're going to cut it should stay in place without issue. By all means use air assist when cutting--do not turn it off. (it is a bad idea because of flame up) You may get some bounce back from the aluminum grid which could be an issue if the plastic is clear. If that is a concern use transfer paper on the back of the plastic.

[Todd Mueller]

I cut intricate shapes in 0.092" acrylic all the time on a honeycomb bed, no problem. Doing the same thing using 1/43" veneer, I'll usually tape it to a sacrificial piece of MDF.
Take that for what it's worth.

when you are cutting the .092 acrylic, do you mind sharing about how many watts you think you are using, or at least the tube you have and what power percentage, and what speed are you at. i wont be cutting anything as thin as 1/43 that i know of in the near future.

[Lee DeRaud]

when you are cutting the .092 acrylic, do you mind sharing about how many watts you think you are using, or at least the tube you have and what power percentage, and what speed are you at. i wont be cutting anything as thin as 1/43 that i know of in the near future.My machine is only 25W nominal (RF tube), so 100% power, maybe 2% speed, which I think works out to ~0.8ips. Edge finish done that way is excellent: I've never felt the need to do any further polishing.

And no air assist, either. I've never noticed any appreciable flare/flame, possibly because of my overkill air extraction and low power.

[Todd Mueller]

that sounds really nice, someone did a test for me on .07 material and felt it would work great at 50watts of power and 15 mm/sec speed with a co2 laser. not sure how that is different in performance from rf as you stated. Is it? so if they were using 50 watts, as opposed to your 1/2 of that at 25 watts, 15mm/sec works out to be about .59 inches/sec so even slower than what you are going and twice the power. maybe i will luck out and find that i need less than 50 watts and can go even faster than my initial thoughts of 15mm/sec or .59"/sec. Sounds like you are getting away with it just fine, unless your laser is different than mine will be in some way, is the rf the same as co2?

[Lee DeRaud]

that sounds really nice, someone did a test for me on .07 material and felt it would work great at 50watts of power and 15 mm/sec speed with a co2 laser. not sure how that is different in performance from rf as you stated. Is it? so if they were using 50 watts, as opposed to your 1/2 of that at 25 watts, 15mm/sec works out to be about .59 inches/sec so even slower than what you are going and twice the power. maybe i will luck out and find that i need less than 50 watts and can go even faster than my initial thoughts of 15mm/sec or .59"/sec. Sounds like you are getting away with it just fine, unless your laser is different than mine will be in some way, is the rf the same as co2?It's still CO2, but uses RF as opposed to the DC glass tubes in the Chinese machines. If that's what you have, you need to de-rate the power by 25%-50%, depending on who you talk to. (I'm told my 25W RF tube is roughly 40W when compared to the typical glass DC Chinese tubes.)

I haven't actually measured the speed when cutting the acrylic, I just extrapolated from the nominal 40IPS max X-axis speed. It may very well be slower than I said...since I'm at max power, it takes as long as it takes.