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Joe Pelonio
09-16-2008, 6:47 PM
I got a batch of 1/4" black acrylic that was $48/4x8 sheet less than most other places, and at the time was happy. Today I got to it in the pile.

Luckily I am using most if it for letters to go high on walls where it won't matter, but none of it will cut with the shiny smooth edge as most do. The cut edges do feel smooth but are dull, and also, there is flaming that requires more air assist. It's not me nor the laser, I tried other brands and get the usual nice results. There is no label or printing on any sheet. The protective paper looks like the old paper grocery store bag material, and comes off easily. I called and found out that it's Acrycast, and is imported from Indonesia. This supplier does also carry Plexiglas G but the price is $150/sheet compared to $103 for this stuff.

Frank Corker
09-16-2008, 7:15 PM
Joe, my brother-in-law who is MD for Altuglas in UK, was telling me that all acrylic when it's first made is clear, colour is added and the reason why it costs more. He also told me that the darker the colour, the more it will differ from clear cast acrylic, if he's correct perhaps it's the density that is causing yours to cut differently. Does it get any better if you reduce the speed?

Doug Griffith
09-16-2008, 7:40 PM
Acrylic is also formulated differently depending on the end use (ie. plasticizers added if it is to be vacuum formed). It could be that what you have was intended for another use. Or just low grade raw materials because it's coming from Indonesia.

Joe Pelonio
09-16-2008, 9:41 PM
This stuff is sold as premium cast, and no amount of fiddling with the settings does any better. I'd guess the process or the raw materials are just different.

And Frank, Yes, I have noticed that clear cuts better than colors, white and
translucent better than black, but I still get great results with other brands of
black including Acrylite which is made in Mexico.

Larry Bratton
09-16-2008, 10:03 PM
Joe:
I got some of that junk too. Supplier had a "special deal" on it. It was absolutely the worst stuff for cutting I ever saw. It had the same plain brown paper on it with no name. It was mentioned in here that it was probably from Mexico...I use a cell cast made by Chemcast from Mexico and I like it a lot, so it wasn't from them for sure. I told my supplier to never again send me any of that particular acrylic.

David Fairfield
09-17-2008, 9:44 AM
I bought a couple of shirts made in Indonesia, they fell apart after about two washings. IMHO "Made in Indonesia" = "Do not buy."

Dave

Bill Morrison
09-17-2008, 10:07 AM
I got that stuff too. I thought I just had the wrong settings but I am going to talk to my supplier to make sure I don't get it again. What I have left I think I'll make some templates for my router.


Bill

Brian Robison
09-17-2008, 10:12 AM
I'm not 100% sure about cast or extruded plastic sense my field is injection molding but.... I'd bet the color is added to clear during the casting or extruding process.
Something to think about, colorants ARE contaminants,
they are added to a pure base material. That's why different colors of the same material cut, engrave and mold differently. It's not unusual to change colors during a run and have to adjust machine controls for a quality part. BTW, in molding, red is usually the worst.Probably why I have trouble with red over white laserable plastic.

Frank Corker
09-17-2008, 12:24 PM
I bought a couple of shirts made in Indonesia, they fell apart after about two washings. IMHO "Made in Indonesia" = "Do not buy."

Dave


Were those acrylic?



:D

Bill Cunningham
09-21-2008, 9:42 PM
I bought a couple of shirts made in Indonesia, they fell apart after about two washings. IMHO "Made in Indonesia" = "Do not buy."

Dave

Dave!! Did you follow the washing instructions 'to the letter' ?;)

Joe Pelonio
09-26-2008, 1:08 PM
Some of the letters I cut from this stuff I had to do over. After peeling the paper there was a cloudiness around the edges that would not polish off.

It turns out that several of my local suppliers are selling this imported Indonesian acrylic now, but I did find that you can get a nicer face if you
mirror the image and cut it backside up.

I told the suppliers about it and they are happy to order another brand for me in the future but I won't get it as quickly.