newbie laser questions and photos on glass

[Ernest Hernandez]

I am newbie to laser engraving. I have been sandblasting glass for the last two years. Now I would like to get into laser engraving. But before I buy an Epilog Helix I would like to know your experiences with engraving glass with a laser, especially engraving halftone photos onto glass. The local Epilog distributor allowed me to do some testing on their Epilog Helix laser. But when I used their laser on glass I noticed that the glass was not as smooth as if I were to sandblast the glass. The distributor said it is because the laser fractures the glass. The halftone photos I tried did not look good. I even tried laser tape and Thermarks LMC98 white, but had mixed results. Your comments or help on lasering photos onto glass would be much appreciated.



Thanks
Ernest:)

[Scott Shepherd]

Your Epilog rep told you correct, it does create the effect by fracturing the glass. Personally, I haven't had stellar results in doing glass, and the sandblasted work I have always seen has always been superior to the results I have seen with the laser. Not to say you can't make something nice with the laser, but I haven't seen the amazing results I expected from lasering glass.

Just my experience, and that might be because I have no clue what I'm doing.

[David Fairfield]

Hi Ernest

The rep is correct, there is a difference between sandblasting and lasering.

Lasering glass is great for many applications but it has its limitations. Big advantage is speed, precision and automation. Disadvantage is lack of depth control you have with sandblasting, and the lack of frosty smoothness that you already noticed.

Also you can't really get a nice feather edge with lasering, because the laser will start making halftone looking dots as it fades to grey. Personally that is not an effect that I like, but some artists may use it to advantage.

But think about this-- you can use a laser to engrave a mask, then sandblast through the mask and get benefit of both methods. :)

Dave

[David Fairfield]

Here is one design I drew in Adobe and lasered to wine glasses, IMHO the laser works best with line art, so I make graphics in black and white, and I avoid large white areas. I've seen some photos very nicely engraved to glass, but it hasn't worked for me yet. Still trying!!

[Ernest Hernandez]

Thanks for all your comments and suggestions. I will give laser tape another try. :)

[Mike Null]

It is not necessary to micro-fracture the glass. I much prefer a frosted finish which you can get by reducing your power and/or increasing your speed. I also do glass at 333 to 500 dpi settings--never higher.

As you have discovered, the laser is clearly not the first choice for marking glass.

[David Fairfield]

Ernest,

Yeah, give it another try! I'm relatively new to lasering myself (3yrs) and so far, nothing has worked right on the first try. On the other hand, I haven't had a problem I couldn't solve with the ideas & help I get here! :)

When I'm doing something on the laser I haven't done before, it always takes me several tries before things start looking right. I now keep a notebook of power & speed settings & results for each material I use. Its helpful.


Dave

[Keith Outten]

Have you tried covering the glass surface with wet newspaper? This will increase the engraving quality considerably but don't let the paper dry out before the engraving is complete. Some engravers cover the surface with dish washing detergent before engraving, it doesn't dry out as fast as wet paper.

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[Bill Cunningham]

Some things you can do with a laser are just about impossible with a sandblaster..The photo on this shot glass is 1" wide, x 1.5" high.. I just did some for a couple that wanted a picture of Niagara falls (The American Falls) and considering the detail of all the rocks at the bottom, it came out quite well.. That picture was 1" wide, by about 5/8" high.. True, the etch is not deep, but then again, you can't etch a photo deep without losing much of the detail. It will never wear off anyway.. As for roughness, yes when it comes out of the laser it's rough, but a quick rinse in cold water, and a rub with a cloth, it becomes smooth to the touch, and has no effect on the visibility of the etch.. I have test glasses in my house that have been through the dishwasher 2 or 3 hundred times with no ill effects..