Hello there!

Im building a laser graving machine from a former 3D printer, and have decided to buy this head to start my quest.
The problem Im having now is that the machine will be in a rather busy place, where lots of people walk by all the time. So, a simple pair of protective gogles wont do the trick, as I wont be the only one needing protection.
Is there a kind of acrylic protective glass I can build a box from? I cant find it in any DIY forums. Is it really necessary to have such protection when using a 500mW laser?

Thanks in advance for any answers.

Best regards,
Afonso Urbano