Laser specs to cut 1/4" Acrylic and Wood

[Richard Ford]

Hi all. I've been reading the forums a while but this is my first post.

I'm curious what Epilog, Trotec or other product configurations people are using to reliably cut quarter inch material (acrylic and veneered plywood). The threads I've read when they compare Epilog and Trotec have focused on raster speed rather than endurance doing vector cutting.

I've been using a 50W Epilog Helix with a 2" lens which has performed well with 1/8" material but cutting 1/4" seems to be at the edge of the machine's performance envelope. Settings for success are varying based on how long the machine's been running that day, and whether it's in the cool of the evening or the heat of the afternoon sun.

To get more consistent results I'm unsure whether changing to a 4" lens, or a different machine is appropriate if I want to get through the material in one pass each time I have a job to cut. I'm interested in hearing what other's would spec (1) if they cut 1/4" occasionally - say a few hours per week or (2) all the time, say 8 hrs/day.

Thanks!

-Richard

[Rich Harman]

I cut 1/4" ply, mdf and acrylic all the time, well not eight hours a day but it shouldn't make any difference if you cut it for one hour or eight hours. If there is any difference in cutting performance based upon ambient temperature or length of time that it has been running (up to several hours), it is not enough to make a noticeable difference. By far the biggest factor in how well it cuts is the focus. Some pieces can be warped just enough to cause the material to be out of focus but not enough to be obvious. Since I have learned to be on the lookout for this I have had very few instances of not cutting through.

I use 80 watts at between 12 and 20mm/sec with a 65mm lens.

For a 50 watt I would expect 7 to 12mm/sec, I have no idea what speed setting that equates to for an Epilog.

A 2" lens should be fine, I think 2.5" is ideal. I would not use a 4" lens for 1/4" material.

[Larry Bratton]

I have a 40watt Epilog EXT. I cut 1/4" acrylic and 1/4" birch plywood quite often. I cut 1/4 acrylic, which is actually about .223 using 100p x 6s x 5000f. If your not getting through the 1/4 acrylic in one pass, you need to think about the age of the tube as it may be losing power. You may also want to check the alignment of the machine. You should get through 1/4" with a 50 watt machine in one pass at about 8s x 100p x 5000f.

[Michael Hunter]

It does sound like a machine/laser-tube problem.

The power is definitely down on my 8-year old 60W tube, but I am still able to cut -

3/8" acrylic : 7S 100P 5000F
6mm acrylic : 15S 100P 5000F
9mm birch ply : 5S 80P 500F
6mm birch ply : 21S 57P 1000F

(When the machine was new, the speeds were significantly faster)

[Glen Monaghan]

Be sure to check and thoroughly clean the lens and mirrors. It doesn't take much smoke from cutting wood to accumulate enough crud on the optics to noticeably reduce cutting performance. I thought my tube was going bad, especially when the cuts started to look odd (like the beam was oval rather than round), but it turned out to just be a dirty lens. I found that I do a much better cleaning job when I remove the lens holder rather than trying in situ.

-Glen

[Steve Kelsey]

Be sure to check and thoroughly clean the lens and mirrors. It doesn't take much smoke from cutting wood to accumulate enough crud on the optics to noticeably reduce cutting performance. I thought my tube was going bad, especially when the cuts started to look odd (like the beam was oval rather than round), but it turned out to just be a dirty lens. I found that I do a much better cleaning job when I remove the lens holder rather than trying in situ.

-Glen

That would be my advice, too. Make sure you clean all the mirrors! The one on the side, too. I was having problems with 1/4" baltic birch on my 40W Epilog mini and did that and was shocked at the performance increase. It is now part of my weekly cleaning regimen. My settings are sp:10, power:100, freq:500 and the only times I have problems are when there is excess glue in the layers of the ply.