Laser Cutting Glass

[boxxer_boy]

Hay ya i have a sheet of glass that i want to put over my alloy V8 block as a coffie table!! i need to figure out a way of cutting a cool design in it and i figured seeing i run a MAZAK laser cutter wondering weather if its possable to be done??

[BrianT]

Glass is opaque to CO2 laser (10.6 micron) radiation. In other words it strongly absorbs the laser energy and heats. You will get choncoidal fractures and ablation from the glass leaving a fairly tacky edge. From what I have been shown, you can etch a design or text into the surface but it looks quite ragged.

Your mileage may vary.

Cheers
Brian

[probinson]

I don't know how well laser engraving does in glass but sand blasting and acid etching both work very well.

Dupont makes a product called RapidMask that you expose to UV and then stick the sheet to the surface to be sandblasted. (There are other brands of abrasive masks but the Dupont one happens to be the one in my hand at the moment.) The portions exposed to UV get hard and will be blasted off by the sand while the unexposed area stays gummy so the sand sticks to it protecting the surface. A really ingenious product that gives very good detail.

The acid etch is similar and can be used with a wax or photochemical mask. What I have is a paste called Armor Etch. The big advantage to the acid etch is that it doesn't stress the glass.

If you use a laser or sandblaster on a piece of glass as big as a table I would talk to the technical assistance at someplace like PhotoBrasive http://www.photobrasive.com (800)643-1037. They sell the supplies and can tell you what is best for your application.

I have had larger sheets or glass simply shatter from sandblasting so You might also need to take your glass top to someplace that makes glass so they can put it in the kiln to remove manufacturing stresses so it wont shatter. It needs to be heated orange hot and cooled slowly (about 10 hours) to relieve the stress. The technical assistance people can tell you what type of glass to use and if stress relief is necessary.

[th-ton]

hi is wonderful , where u from

[Lon Salgren]

Don't use laser. Use either water-jet or sandblasting. I'd strongly lean toward water-jet.

Lon

[jerryrig]

I have cut glass with a laser (co2) both free hand and mounted in my mill, even though i had some sucess I don't advise it because it fractures all over the place and glass dust and chips are very dangerous and take years to get out of your workshop

[qroger]

JerryRig makes a good point. Before there was miners black lung, there was silicosis. Before the invention of the water cooled rock drill, the miners would work in a cloud of dust all day. If the mine was in hard rock, the dust would be tiny chips. Eventually these chips would cause little ulcers in the lungs, kind of like emphysema or pneumonia. Terrible way to die. There was one mine in particular, I think the Atlanta mine in Utah. The rock was basically flint, (glass more or less) and the mining occurred when power drills had been invented, but they weren't water cooled. More or less 100% of the people that worked there died of silicosis, even with short exposure. That's why bags of concrete or sand say not to breath the dust....

Water jet sounds like the way to go, if it is available.

[Neil Pritchett]

Hi all,
Redsail CO2 lasers will work well with glass. especially if you use Photograv software to process the image first.
As for the dust; quite right, avoid it for health reasons. However, waterjet is quite expensive. The alternative is to use a filter system on the laser exhaust. In the UK these are about £1400 for a three stage filter system including Hepa and activated charcoal. This will remove all the dust particals and chemical fumes from other materials. Final note: If you are going to buy a filter system, ensure the supplier knows the materials you are going to be processing. There is a wide range of filter packs to suit different chemical fumes.
best regards. Neil (for ctrlasers.co.uk)

[gamasutra]

I would highly recommend using waterjet over glass for your particular case, since heat from the laser will likely damage the glass.

Tim
http://www.luckywaterjet.com