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View Full Version : Is there a perfectly unlaserable "glass"?



Alan Reilly
03-25-2013, 9:31 AM
I am searching for a substrate for a project. It needs to be clear and unlaserable...meaning that the laser will not etch or engrave it at all.

Is there such an animal?

Joe Hillmann
03-25-2013, 10:20 AM
What type of laser? There are quite a few types of lasers and each one reacts differently to materials. A CO2 will engrave the surface of most glass, a yag will pass right through most glass.

If you are looking for a glass that CO2 won't touch you may want to figure out what the focusing lenses are made of, the light passes through them without marking them but that may just be because it isn't focused yet.

Alan Reilly
03-25-2013, 10:40 AM
I am sorry...yes, it is a 35 watt CO2 laser.

Joe Hillmann
03-25-2013, 10:48 AM
What are you doing with it?

After I thought about it I doubt even the glass used for the focusing lens would work because the energy density/area is 2500 times more at the focus than it is at the lens.

So if you can tell us what you are trying to do someone here may be able to help you out. For a 35 watt laser borosilicate glass MAY work. Highly leaded crystal MAY also not be touched by 35 watts. But like I said , knowing whayt you want to do with it will help.

Mark Sipes
03-25-2013, 11:48 AM
My 25w seems to mark just about all glass I have put in it...

Do want the laser to bake on a surface without etching.... boil water .... laser inside the glass vessel ??

Martin Boekers
03-25-2013, 11:56 AM
If you are planning to use this in the open without the beam being encased ( covered like in our machines ) You are playing with fire so to speak.
We operate class 3 lasers, covered. I would do some background searching and check with local laws on this. Rock Concerts promoteres have to go though
quite a bit and have inspections before their shows.

Not know what your plans are I thought I would throw these concerns out....

Dan Hintz
03-25-2013, 12:29 PM
Glass? I'm not aware of such an animal. The particular structure of glass does not lend itself to transmitting CO2 wavelengths... same thing with any organic (acrylic and such) I'm aware of...

Alan Reilly
03-25-2013, 1:31 PM
Joe: wanting to paint the matl and laser the paint away, leaving a crystal clear mark with no etching.

Martin: No, nothing like that.

Dan: Yeah, that's why I put glass in quotes. Maybe there is some clear matl that is not affected by a CO2 laser. But maybe not.

Joe Hillmann
03-25-2013, 1:41 PM
I can't think of any way to make that work, but you could mask the glass, use the laser to cut your design, peel away the area you want colored then paint it.

There are some types of borosilicate glass that may work, the laser chips away at them but they remain clear, although there are several types of borosilicate glass and some engrave nearly as well as glass, some turn the engraved area into tiny slivers of glass that you will find for months to come after engraving it and some stays nice and clear. I've done all three and there is really no way to identify one form the other or even from regular glass. Although in general borosilicate glass is usually used in glass that need to withstand large heat changes and be very strong.


Edit: You didn't say, but if the reason you want the unpainted area to remain clear is you want to paint it another color it isn't necesarry. If you paint on a frosted piece of glass the frosting will completely disappear and it will look as if you painted on unetched glass.

Gary Hair
03-25-2013, 1:58 PM
How about doing just the opposite? I have a sandblast mask that comes off very easily after soaking in water. I would laser away the parts you want painted, paint, soak and remove the mask. The mask is made by Ikonics and is called Laser Tape. There are others on the market that are similar, but none that come off by soaking.

Gary

Martin Boekers
03-25-2013, 2:24 PM
Joe: wanting to paint the matl and laser the paint away, leaving a crystal clear mark with no etching.

Martin: No, nothing like that.

Dan: Yeah, that's why I put glass in quotes. Maybe there is some clear matl that is not affected by a CO2 laser. But maybe not.

You may check with a paint company and find a paint that has a low vaporization point. It's seems I have done something similar a few
years back doing multiple low power/higher speed passes and it worked pretty good. Something you may experiment with.

Scott Shepherd
03-26-2013, 9:16 AM
That process works just fine. You just have to take multiple lower power passes rather than trying to get all the paint off at once.