Engraving Polycarbonate

[Liesl Dexheimer]

Will engraving a polycarbonate produce a clear result?

[Bert Kemp]

I don't understand your question. a clear result would be invisible

[Liesl Dexheimer]

I have a customer who wants me to engrave acrylic glassware. She said they are a polycarbonate. I've engraved acrylic that was most likely a polycarbonate in the past and it produced almost a clear engraving. You could barely see it (very little contrast). I know cast acrylic is the best to engrave since it will produce text and graphics that are white and extruded acrylic generally produces a silverish or almost clear result.

[David Bassett]

I'm not an experienced user and I don't know much about the chemistry of materials. I do clearly remember our Maker Space's training included a list of materials that were approved and banned. Acrylic and Polycarbonate are different. Acrylic was approved and one of the most cut and engraved materials. Polycarbonate was banned completely, (no warnings, lose your membership on the spot level ban,) because it out-gassed something extremely toxic. Since I don't understand the reason, I can't say don't do it. But doing your own research into what your customer really has and how to safely handle it seems like a good idea.

[Liesl Dexheimer]

Thank you David. I thought it might not be good to laser, just couldn't really remember. I know vinyl is a big no no because it can be caustic to the laser and your lungs.

[Kev Williams]

Depends on the laser--

Polycarb under C02 laser will resemble plex engraving, mostly clear, but polycarb gives off a thick yellow smoke that stains the engraving. Not horrible but noticeable, and I've found nothing that will get rid of all the yellow.

Polycarb under fiber laser goes black, but can be hard to control; the surface being engraved boils and pops, and turns black, and the boiled poly can remain as raised and a bit lumpy.

Here's 2 pics of the same piece fiber engraved on the top side. With bright white behind it, looks quite black...
DSC05686.jpgDSC05687.jpg
but when viewed from the back in reverse it looks as if it was tool engraved cleanly and painted black...
--I don't have any C02 lasered poly...

>edit< -- and the acrylic in the past you engraved but didn't show up was likely extruded acrylic...

[David Bassett]

Thank you David. I thought it might not be good to laser, just couldn't really remember. I know vinyl is a big no no because it can be caustic to the laser and your lungs.

You're welcome. I wish I knew the whys and chemicals to be more helpful.

Just another point of reference, in the Maker Space rules there was no Vinyl, because it gives off chlorine gas which is corrosive to the equipment and not good for you or the other users in that space (being it's a major part of WW1 mustard gas). But Vinyl IIRC only got you a "timeout", i.e. you're done for the day, go home now and think about your poor choices, and never do it again. Not nearly the Polycarbonate immediate permanent ban.

[Mike Null]

Liesl

I have engraved polycarbonate with a co2. You will not achieve optimal results due to the discoloration and the clear, rather than frosted, engraving. If you have a test piece, a light pass might produce acceptable results. Do not try to cut polycarbonate.