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George Elston
09-01-2007, 12:22 PM
I've have the opportunity to put my business cards into several shops and thought the boxes would be "cooler" in plexi. I have an intricate design that I usually cut out of wood for BC display. However the stuff I picked up at Home Depot doesn't cut very well for tight intricate designs. It only says PLGA 080, the 080 being the thickness. I have tried all kind of different settings and they all cut but the plastic deforms and sticks to itself from the heat. Can someone recommend something easily available (Lowes, HD, etc) that will cut well. Or is it just me? Do others cut this stuff without a problem? Have attached file so you can see what I am trying to do.

Mike Null
09-01-2007, 3:01 PM
I've cut that stuff without any problem. Try lowering your frequency and maybe increasing your speed.

Lee DeRaud
09-01-2007, 3:32 PM
For 30W VL, the "dumb" (material-based) driver's settings are just about right for Home Depot acrylic in either the 0.08" or the 0.2" thickness. I've used the thinner stuff for the "icicle" ornaments posted here, so intricate shapes are obviously not an issue. Are you sure you didn't pick up polycarbonate by mistake?

For the advanced driver, the "book" says 60% power, 0.5% speed, 1000 PPI for 0.2" acrylic. I would just try speeding it up to 1% for the thinner stuff.

Mike Null
09-01-2007, 5:50 PM
I switched from HD to Johnson Plastics as theirs has a paper cover instead of plastic. I was cutting simple "window rectangles" and I don't like cutting through the vinyl cover as it sometimes sticks to the material. Also, my customer likes the windows to be shipped with the paper in place.

Joe Pelonio
09-01-2007, 6:27 PM
The plastic covered acrylic cuts just as well, but I'll remove the plastic film and replace it with transfer tape.

George Elston
09-01-2007, 6:49 PM
Are you sure you didn't pick up polycarbonate by mistake?

For the advanced driver, the "book" says 60% power, 0.5% speed, 1000 PPI for 0.2" acrylic. I would just try speeding it up to 1% for the thinner stuff.[/quote]

Is there a simple test for polycarbonate, I thought I remembered reading somewhere that polycarbonate will "bomb" i.e. drip globs when burned. This stuff just gives a yellow blue flame and turns to what can best be described as a gob of spit (sorry gals).

My Materials database gives me 100% pwr 6.4% speed 1000ppi Course I have the new version, but that seems in the ballpark

Larry Bratton
09-01-2007, 7:17 PM
George:
I see from your profile you are in South Florida. I buy acrylic from Piedmont Plastics here in my area. They have two branches in Florida, one in Daytona and one in Pompano. They have excellant prices and what you get from them you can rely on to be what you are expecting. I have compared their pricing to several of the online sellers and they beat them every time, at least the pricing I get from my local branch. I cut 1/4" acrylic with my 40watt Epilog at 6S/100P/5000 freq.
Good luck!

Scott Shepherd
09-01-2007, 8:53 PM
I use Piedmont Plastics for my Acrylic as well. Talk about a smart group of people. It's nice to speak to people who don't answer "huh" when you say "Does this material have any PVC in it".

George Elston
09-01-2007, 8:55 PM
Ok, so do I open my mouth and prove I am stupid, or remain silent and ya'll will only suspect. I took a look at the lens and remembered that the last stuff I had cut was some painted paper, that we have a lot of since I told my wife that I would never cut painted paper again since it really fogs up the optics and the pre-filter, (but it's only a couple of pieces). With clean optics it's amazing how much better the laser works.

But, thanks to all, I wouldn't have looked at the lens, I just cleaned it yesterday, if everybody hadn't said it works fine on my machine.

Maybe we should have an FAQ that reads, clean the lens check the focus, for every problem under the sun. I usually do it, but not this time.

Thanks again

Mike Null
09-02-2007, 8:33 AM
George
Just so you don't feel like the Lone Ranger--a while back I was engraving a large image on some wood. The image had blotches of area which hadn't been engraved though I first thought it was residue from the engraving. I ran it again to clean up the mess and it happened again.

I put in a call to tech support and fortunately was not able to get through. I kept wondering what happened when I noticed some debris clinging to the bottom of the cone on the lens. I removed the cone to find that it was at least 50% clogged with engraving garbage which had been blocking the beam. Duh!

Larry Bratton
09-02-2007, 8:41 PM
George:
Right, don't feel bad. One day I was helping Scott Shepard on some testing and my machine was giving funky results. All of a sudden, while running the second test, a mirror FELL out on the table!!! Seems that my wife, who helps me, cleaned it and didn't get it tightened up good and out it came. (This was early on, very soon after acquiring it) Since then, I oversee or do the optics cleaning myself. Needless to say, it was a bit embarassing. :)

Larry Bratton
09-02-2007, 8:55 PM
I use Piedmont Plastics for my Acrylic as well. Talk about a smart group of people. It's nice to speak to people who don't answer "huh" when you say "Does this material have any PVC in it".
Or..is this CAST or EXTRUDED? They know the difference. They also will cut and fabricate for you. They are a good outfit. They can fill a lot of needs, as they also sell print media,ink, plotter vinyl etc.
http://www.piedmontplastics.com

Stephen Beckham
09-03-2007, 7:45 PM
George,

If we were going to hijack this thread and turn it in to most embarassing moments - you wouldn't be alone - I myself could bore the group with a laundry list far more embarrasing than that of a dirty lense.

I'l like to use your CDR for a BC holder in my store if you have no issues with it...

George Elston
09-03-2007, 9:15 PM
No problem at all, I'll even send you some of our business cards to put in it. Oh you mean for YOUR business cards. Still no problem, this was not an original design, the bottom of the box was posted here some time ago, and the top was from a file, I got from the ULS rep. I did modify the top part to cut so small and it does not have the detail of the original piece. If anybody wants the original of the horse and carriage, with all the detail, I'll dig it up and post it.

If this thread does get hijacked, and we all manned up to our bloopers it might be most educational and very entertaining.

But then again, I only fessed up because I was in a position of receiving a lot of help from a lot of very selfless people for a problem that didn't exist. Sufficient to the day is the evil there of. I would hate to waste all the brainpower here, there's too many times I really need help, and this is where I turn.

But .............if someone wants to start a bloopers thread...............Nothing is as funny as someone else's educational experiences.

Bob Cole
09-04-2007, 2:51 AM
Thanks for the file. I just ran it and it turned out pretty good. I did it in 1/16 clear cast and when I put all the pieces on my settings manual, it disappeared. What do you recommend to make this stand out a little more? I was thinking that raster engraving the clear areas would really help.

I am also wondering how well this will stand up when someone gets a card? The light post looks like it will break off if I look at it wrong :) .

I will try and glue it tomorrow so wish me luck.

George Elston
09-04-2007, 10:32 AM
Actually I'm still working on mine, I thought I'd pick up some .2 material today, and give that a try, your right it is VERY delicate. I've done a lot of these cut from .125 door skin, or other woods and after several months they are still intact. But the plex is a bit of a problem. The lamp post on the one I cut from .08 seems like it would take a bit of punishment, but only from an adult, a small child could do it in. One thought, only cut the major interior areas and etch the details on the leaves, etc. and fatten the lamp post and reigns. The other idea is to keep doing it in wood, but I keep thinking that clear could be very impressive.

I have attached the original file, so you can get an idea of the reduction in detail, and for your lasering pleasure. It's v11 and I had to zip it to get the file size down.

Ray Mighells
09-06-2007, 12:45 AM
That's a neat little box. Has anyone resized the tabs for 1/8th acrylic? I cut one without checking for tab size. I know how to create a tab, but I don't know how to resize one on the bottom edge. Thanks to anyone that wants to post it.

Bob Cole
09-06-2007, 12:45 AM
Thanks George. I will try on wood next.

George Elston
09-06-2007, 7:44 AM
Yea, I always have to think about that one too. But the bottom is the bottom, so the bottom always stays where it is, and the top of the slot moves with the thickness of the material. That is assuming you moved the top of the slots up on the front and back.