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Comment by noonespecial | Hacker News Reader

The Lexan inlays are laser cut to a precise, water resistant fit (from Rideye campaign page)

A little off topic but the Epilog guy told us never cut Lexan or any polycarbonate plastic because it makes a chloride gas thats dangerous to humans and destructive to the laser. But lexan rocks as a building material... So FUD? or does it require special considerations?

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Sounds like you might be mixing two bits of advice. There are many materials you never cut with a laser cutter, such as PVC or vinyl (makes chlorine gas) or ABS plastic (makes cyanide and melts). Thick Lexan shouldn't be cut with an infrared laser, not necessarily because it produces harmful materials but because it will scorch and burn rather than cut. You might be able to cut it with a different type of laser cutter. And some other forms of polycarbonate may cut better (materials informally called "Lexan" sometimes aren't). You would need some detailed knowledge of the exact material and laser cutter, and thus some expertise.

See http://atxhackerspace.org/wiki/Laser_Cutter_Materials for some details.

I'm literally going to print that page and hang it over the cutter. Thanks.

Note: That page does say in the second paragraph: "It is not always obvious which materials will work - for example: Polycarbonate/Lexan produces flames and lethal chlorine gas which will rapidly corrode this $40,000 machine into uselessness and which is extremely hazardous to the health of people nearby." That sounds like its in shouting distance of the Epilog guy's warning.

Polycarbonate doesn't have any chlorine at all in its chemical formula. Maybe the usual types of Lexan contain plasticizers/flame retardants/other additives that contain chlorine?

Which is exactly why I ended with "You would need some detailed knowledge of the exact material and laser cutter, and thus some expertise."; cutting any kind of polycarbonate sounds like a bad idea if you don't know exactly what you're doing.

The London Hackspace Wiki has a little write up on how to test plastics for Chlorine: https://wiki.london.hackspace.org.uk/view/Laser_Cutter/Instr...

Chlorine, not chloride.

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