laser etching dichro ?

[ShttrdSpctrm]

so a friend of mine took some dichro and tried to etch it with a laser that he uses for work. Well, the first time he did it , they came out ok but the print was backwards. :bangHead: So he tries again , gets the print the right way but now its all scuffed up, kinda looks like devit. he tries again, same results only the "devit" looks worse! We were thinkin it might have somthin to do with the laser bein too hot or just scratchin the glass. anyway, we were wonderin if anyone would be so kind as to hand out advice on what we might be doing wrong or to try a diff setting on the machine. maybe its not the right machine, i dont know. thanks so much for any help. peace, chris

[Greymatter Glass]

You need a fairly powerful CO2 laser, a VERY powerful Diode laser, or a pulsed Nd:YAG or ruby laser.

then you have to tune your equipment for the "right" cutting rate, no idea what that will be for your laser. Too fast and you'll leave behind scum... not sure what too slow would do. Eventually going really slow might heat up the glass and cause devit, it might even happen on a microscopic level....but I kinda doubt it.

My suspicion, without seeing the images anyways, is that you went too fast and left behind a layer of something (metal, quartz or, both) It will look like devit, but it's probably just in need of a little slower etching.

Any idea what kind of machine you have access to? I could get it's stats and do some math and maybe figure out what speed to cut... but it would probably be best to just do trial and error till you get it tuned in.

Also, each dichro coating is different thickness from color to color, so what works for grass Green might not work on rasta Gold, or something.

if you get your laser tuned in SUPER tight you might even be able to selectivly etch diffrent dichro colors out of a thick coating. that would be cool.


Anyways.... I looked into building a laser for an X-Y table, and the cheapest I could build a laser for was like $300-400 and the cheapest commercial units are 10x that. So I went with chemical etching, and it wrks great. sharp lines, fast turn around... just toxic and messy.

-Doug

[steven p selchow]

I posted awhile back, but for a few images I cut some dichro to the size I needed, then used etchall on it to remove the dichro where I didn't want it, and it worked, if your doing a lot, this probably wouldn't be feasable, but it will work, or did for me.

steve

[FredLight]

When I was laser-ablating images with a C02 laser, it was a 25 WATT laser being run at 30% power/100 percent speed.

You can't selectively cut out colors out of super thick dichro. I tried for months.

[ShttrdSpctrm]

thanks a ton for the response. i'll try and get him over here so he can tell more about the laser. from what grey said , it might be too fast.
we are tryin to get it down so we can do full sheets of images. custom and what have ya

[ShttrdSpctrm]

well im the one doing the etching. i've been using a Universal x2 100watt laser, ive had it set at 4% power 55% speed. 3% power leaves "scum" or residue durco coating, and 5% power etches the glass to deep and when torched turns very hazy. however 4% power still comes out somewhat hazy. so im gonna tweak the speed settings more and probably make it work.
however i was wondering if there is a particular type of dicro that etches better than another? beside the power settings are there any other variables to work with? thanks for the help already.