Acrylic laser shield?

[Ben Dalton]

Ok, I need some advice from people smarter than I am... My company is now the proud owner of a Kern large format laser, but it is an open type (I think they call it class 4) laser that you need to where protective glasses when in the room and the laser is in operation. What I would like to do is hang a piece of acrylic from the ceiling that I can pull down and will hang down, in front of the machine, blocking any stray laser radiation. This way, if someone (like an employee) walks through the room while the laser is working, any radiation is blocked, and I don't need to worry about someone not putting on glasses and getting laser radiation in their eyes. My question is, is it a special type of acrylic that needs to be used, or will just regular, 1/4 in thick clear acrylic work? I know I could just use opaque acrylic, and I'd be fine, but I'd like to use clear (even if it's colored) so the working laser is still visible from anywhere in the room. Any expertise would be greatly appreciated!

[Gary Hair]

Regular acrylic absorbs co2 laser. No need to go with 1/4" thick, 1/8" would work fine. At the distance you will be away from the machine there isn't much chance the beam is focused enough or powerful enough to penetrate - unless you have hundreds of watts anyway.

[Kev Williams]

Even 1/16" would be fine.

Even canvas window vinyl would work-

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and it could be made to simply roll up and down like a window shade...much easier than muckling with full sheets of plex--
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[Ben Dalton]

That's the info I was hoping for. The laser is a 100 watt, so I should be fine, right?

[Ben Dalton]

Purely for fun, color wouldn't make a difference, right?

[Gary Hair]

Black absorbs more energy than clear so it would take much more power to penetrate. Other colors do as well, but nowhere near black.

[Gary Hair]

That's the info I was hoping for. The laser is a 100 watt, so I should be fine, right?

The lid on my 80 watt is 1/4" thick, you should be fine with 100 watts.

[Ben Dalton]

One last follow up question....So before I posted here yesterday, and was researching the original question online, I found companies carrying "laser-safe" acrylic sheeting... One of those sights said for my 100 watt CO2 laser I needed to buy their sheeting (.14 inch thick) that was 130.00 a square foot! Any ideas how they could charge that much, when everything I've found (including here) says, clear, regular cast acrylic blocks pretty much all of a CO2 laser's light (10600 nm). I can buy a whole 4'x8' sheet from delvies for less than a foot of their stuff!

[Gary Hair]

They charge that much because they can... people are obviously paying it. Every laser I have seen has standard acrylic for the door, I'll stick with what I know works. If it's good enough for the big-name manufacturers then it's good enough for me!

[David Somers]

Ben,

I believe the price charged for the "laser safe acrylic", along with many other commodities to which you can apply fun adjectives, is in direct relation to the boat payments (ship payments?) or alimony/palimony payments the owner of the company is making.

Just a cynical observation. <grin>

Keep in mind there is a fluff news piece going around now about Nieman Marcus charging $69 for a frozen box of Collard Greens, plus $15.50 for SH. Admittedly, there are bacon bits in it. No thought should be given to the fact that you can buy roughly 2 thousand servings of collard greens for $69 by going to the grocery store.

Why would they do this? Because they can, and because someone will pay it (they are currently sold out) and because the owner of NM clearly has high boat payments to keep up with.

I wonder what I could earn if I froze Kale? Hmmmmmmmm! And then laser cut it into unique shapes????? Ooohhhhhhhhh! Artisan Laser Cut Organic Gluten Free Kale!!!!! OMG!!!!! <grin>