How To Differentiate Between Acrylic and Polycarbonate?

[Gideon]

Hi.  I'd like to learn something today:  Is there any way to differentiate between acrylic (a.k.a. Plexiglass) and polycarbonate (a.k.a. Lexan)?

I ask because people say that acrylic scratches easier than polycarbonate, but polycarbonate is easier to cut.  To me, with no hands-on work with either material, this doesn't mean much.  I would like to go to an arcade, see an old cab, examine the CP overlay, and judge for myself whether there are too many scratches.

[NoOne=NBA=]

Actually Lexan scratches easier than acrylic.
Acrylic is harder, but more brittle.
If you aren't careful cutting acrylic, it will shatter on you.

For straight cuts on either, I would recommend taping the area you plan to cut, and then cutting through the tape and all.
We actually had to get a special blade at work (from a plastic shop) to cut the acrylic.
If you are using a jigsaw, use a very fine tooth blade, and cut very slowly.

Lexan is easier to work with because it is softer, and more flexible.
The same cautions apply to cutting it, but you are less likely to have "accidents" with it.
I would recommend acrylic for most arcade applications (especially monitor bezels) because it is also a little clearer than Lexan.

On my cabinet, I used acrylic for the monitor bezel, and made the CP overlays myself using .010 Frosted Lexan.
That is the same stuff used on most of the gas pump & ATM overlays you see out there.
Most of the arcade overlays (Defender/Asteroids/etc...) used that type of Lexan.
I used that because I could print directly on the back of it at work, and it didn't require the "extra" piece of thicker acrylic to cover it.

As far as how to differentiate between the two, the protective cover marking is about the only way to do it easily.
TRUE Lexan will always have printing showing the GE logo, and saying that it is Lexan on the protective cover.
Off-brand polycarbonate may, or may not, be marked.
If you buy the stuff from a plastic place, they should sell you the right type.

[patrickl]

Yeah, I guess the best way to tell which is which is to read the label attached. You could tell the difference on feel, but then you would need to know what to feel for. I guess "brittle" is the feel you get from acrylic and "tough" from polycarbonate. But from looking at it as it's placed on a CP I gues that would be pretty hard. Scratching it might be an idea (bad idea perhaps   but still )

Personally I like glass better than acrylic for the bezel (tempered tinted glass) and marquee. Acrylic tends to go translucent over time and glass scratches even less easily.For the CP I don't like clear plastic very much. I started out my design with putting Lexan on the CP, but it didn't look "retro" enough to me (apart from the fact that I couldn't get it to bend) So, like NoOne=NBA=, I'm going with a laminated print too. Allthough I'd sure like to know where he found the 0.010 frosted Lexan. Allthough I probably will just have my artwork printed at classicarcadegrafix.com

[NoOne=NBA=]

The .010 is industry standard for control panel overlays.

[patrickl]

The .010 is industry standard for control panel overlays.

But can you just buy that somewhere?

[Brad Lee]

Destructive Testing  

Bend it! If it bends very little before snapping, it's acrylic.
Saw it! if you can cut it pretty easy with a saw, its lexan. If it starts to chip, splinter & crack almost immediately- Acryllic

Really though, if you got a piece and its not marked, and you dont know the different feels, you might need to find a scrap edge and try it out


For straight cuts on acryllic/plexi, for a single piece anyway, the easiest way is to lay the piece flat on your workspace, get a metal straightedge(i used the edge of a level), and repeatedly "trace" the line you want to cut with a razor blade(or the correct tool i suppose, should be hanging at the store right next to the sheets of plexi) When you've got a good score line, slide the piece to the edge of your table, so the scrap piece is hangiong over the edge, line up the edge with the edge of the table/counter. I again line up the straightedge on the table side, apply enough pressureto keep it sturdy, and give the scrap side a good WHACK! It *should* snap off right along your line

For polycarb/lexan, you should be able to work with it just like you would a piece of wood- same drill bits, same blades, etc. Carefull with any electric tools- they heat up and can melt/scorch your piece, as well as gunk up your blades with melted plastic.

For both, if youre drilling, youre probably gonna be better off sandwiching your piece betwen 2 scraps of wood & clamping to keep it nice n tight. This will help keep the edges of your holes from chipping, cracking, especially with acrylic


Personally, I used 1/8" clear lexan on top of 5/8" wood (3/4" total) for my control panel, with printed graphix between. I used tinted 1/4 or 1/8" plexi for the monitor bezel, cant recall which right now. I used plain old 1/8 or 1/4"(again cant recall) for the marquee, since it just needs to be a flat plain piece in my case

[Gideon]

Thanks for sharing info, guys!  A lot of this stuff I didn't know.