What thickness of acrylic will a 40w Epilog cut? and..

[Larry Bratton]

In about a week, I am going to receive my new Epilog EXT with a 40 watt tube. I am under the assumption that I should be able to vector cut 3/8" thick acrylic. Right?
But say I need to cut some 1" acrylic. Can you do this is in multiple passes with good results? If not, what do you do? Cut it with another tool?

[Frank Corker]

You will struggle. The cut will not be nice at all, most likely will require to be finished off by hand flame polishing. I have done 20mm but it was a real struggle even with a 45 watt and a rough finish.

I'm sure there are one or two here who have 100 watt who would fair better. In the Epilog handbook 9.5mm is recommended to have 2 cuts with a 75 watt laser at 3/100/5000 so I wouldn't hold my breath

3/8ths with a 40 watt has same settings as 45 and they recommend 3/100/5000 and that is a pretty easy cut with air assist.

.

[Larry Bratton]

OK Frank, that being said, what thickness CAN you do with your 45w without reservations about the quality etc? I guess I could throw the stuff on the CNC, that'll do it.

[Frank Corker]

Larry I do a lot of stuff with 9.5mm as I have access to a lot of it, that's the main reason, I don't actually do much cutting on wood products. By the way, when I do cut this acrylic, it seems to take forever, if I had CNC, I'd use that for the main cuts and flame polish by hand. It takes a steady hand and a lot of nerve but you can get fantastic results.

[Larry Bratton]

9.5mm being 3/8" then. I have a 50"x100" CNC router with 5hp spindle. I suspect if I had a job requiring a quantity I would probably cut it there anyway.
I would guess that the Epilog would handle 3mm without a problem..right? I make a lot of engraved plates (rotary) that go on doors. I am hoping to be able to engrave and cut these out of Rowmark 1/8" plastics in one operation.

[Mike Hood]

My 40W ZX will cut 3/8" and I labored through a piece of 1/2" once. I'd say to be fair that 3/8" is about the single-pass limit.

[Rodne Gold]

Your limit is the focal point of your lens and its convergence and divergence from that point rather than your power. You will cut 8-10mm with ease.
With a 4" lens you can cut 1" with a struggle.

[Larry Bratton]

Your limit is the focal point of your lens and its convergence and divergence from that point rather than your power. You will cut 8-10mm with ease.
With a 4" lens you can cut 1" with a struggle.

Rodne, this machine comes stock with a 2.0. Should I consider the purchase of a 4.0? Do you have a 4.0 and if so, how often do you use it? From gathered information it appears that a 2.0 length is a pretty good all around lense. How about a 1.5? Do you own and use one of these frequently?

[Gary Hair]

Your limit is the focal point of your lens and its convergence and divergence from that point rather than your power. You will cut 8-10mm with ease.
With a 4" lens you can cut 1" with a struggle.

I thought that convergence/divergence were a non-issue with acrylic. Apparently the optical quanlties of acrylic actually kept the beam parallel and that power was the biggest concern.

That's is what I have heard but I don't know if it's true or not...

[Rob Bosworth]

Larry, if you have a bunch of 1" thick acrylic to cut, you might look into using a good laser job shop. I can't believe the prices some of these good quality laser job shops charge to cut large quantities of acrylic, or wood. There is a laser job shop in Ripon, WI. that has a bunch of higher powered lasers over large XY tables. They can run some of their jobs with mulitple heads, do a really nice job, and their prices were fabulous. The guys in Ripon are set up to run plastics and woods. And they have been doing it for a long time.

[Rodne Gold]

Acrylic does act as a waveguide of sorts (IE limits the divergence of the beam) but not enough to cut unlimited thickness. 1" acrylic is real thick , its expensive and regardless of what you do , its very difficult to get a good cut with it.
The other side of things is that you are gonna put a LOT of heat into 1" or thick stuff , so you are going to have a big problem with stress cracking etc with these types of thicknesses , even 10mm (under 1/2") is going to be problematic in this regard.
I have a 1.5" and 4" lenses as well as the std 2" lenses and hardly use them , they were expensive and have never *really* justified their cost. The 4" lens is really only good for cutting where kerf width is not an issue and the 1.5" lens can really only work on dead flat stuff. I wouldnt buy em unless you have really good reasons to do so.