Wanted to double check material type before proceeding with a cut

Laser
#1

I just started a print on the laser cutting using a clear acrylic sheet I got from Home Depot, but wanted to be extra sure I’m using the right type before proceeding.

I made sure to test it to make sure it would snap cleanly rather than bending (to avoid the type that creates chlorine gas when cut), but there was still a faint white residue on the bed after I did a test run on the full spectrum laser.

Is there anyone at the makerspace now who would know more about this?

I just don’t want to accidentally create harmful vapors or cause any damage to the laser cutter.

Thanks!

  • Chana
#2

If it’s acrylic, it’s fine - polycarbonate (Lexan) is what you want to avoid.

#3

Do you know if there is a way to tell the two apart? I’m fairly certain I got acrylic, but it’s possible I could have grabbed the wrong type at the store.

#4

based on your explanation, there is no way for us to tell. Could you send a picture of the material and it’s labeling?

#5

The label from Home Depot will tell you if it is acrylic or polycarbonate. If the label has been peeled off you can tell by how flexible polycarbonate is. Of course trying this may snap your acrylic. :wink:

#6

Poly carb vs acryllic i guess the only way to tell is break it, but I’m not sure I would be confident either.

#7

Alright, thanks! The label must have peeled off, but it does snap when bent so I’m guessing it’s acrylic. :smile: (It’s also been in my car for a few months and hasn’t yellowed, which sounds more like acrylic than lexan?). I was just worried because of the smell and the lines on the bed after I cut out a piece, so I wanted to make sure.

I’ll give it a try and if it seems wrong for any reason I’ll just stop the cut and go buy something I know for certain is acrylic.

Thanks for all of the help, everyone!

#8

Also polycarbonate is lousy to cut and the edges will seem greasy.

No I have not cut any on our laser but have seen it done by accident.

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#9

If you take a pair of pliers (while wearing safety glasses) and grab about 1/4 inch of a corner of the sheet and bend the crap out of the corner then it’ll either break off cleanly which is acrylic or it’ll bend and turn cloudy which is polycarbonate.

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#10

While this isn’t a certain way to tell, polycarbonate also tends to be about twice the price of acrylic.

#11

This reminds me of a flame test we used to use to test whether plastic was safe or not… :wink: :slight_smile:

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#12

I was also taught this.

I’ve seen a lot of people perform the test badly, which makes it worthless. PVC insulation was a common culprit.

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