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Ernie Martinez
09-11-2012, 4:29 PM
Sorry for the barrage of questions but I'm having a blast with my new machine. Today I tried the rotary attachment and cracked 6 glasses. I kept reducing the power and increasing speed and dropped the frequency to 1000 and that allowed me to get 1 done without cracking the glass. And yes I wrapped it in wet newspaper. But I'm not happy with the result. It's very rough to the touch, very low in contrast and the letters are very jaggy (if thats a word). I ended up with 35% power 100% speed and used vector mode.

My question is this, for straight text should I use vector or raster engraving?

Steve Kelsey
09-11-2012, 4:32 PM
Raster mode, for sure. I've done 1000's of wine glasses and never cracked one. I don't use newspaper. I engrave, with a 40W Epilog, at 600dpi, 45sp and 100 power. Hope you get your issues figured out. My customers love the glasses.

Gary Hair
09-11-2012, 4:56 PM
But I'm not happy with the result. It's very rough to the touch, very low in contrast and the letters are very jaggy

That's what lasering glass usually gets you. If you want to engrave glass you really need to sandcarve instead of laser.

Gary

Ernie Martinez
09-11-2012, 5:01 PM
Raster fixed the issues, thanks to all.

Mark Sipes
09-11-2012, 5:18 PM
I have a 25 watt and I use 100 p, 12 s, 500dpi and Black 80% raster. Experiment with the % black fill. that will reduce the jagged feel.....

Tim Bateson
09-12-2012, 9:51 PM
...And yes I wrapped it in wet newspaper...

Skip the paper. Use dish soap for thin glass and nothing on thicker glass/crystal.

Ernie Martinez
09-13-2012, 12:44 PM
Thanks for all the advice. Where do I set the black levels?

Martin Boekers
09-13-2012, 1:50 PM
Dish soap does give slightly more contrast and makes it smoother to the touch. I always use a small brush to get the "shards" out before giving it to the client.

Mark Sipes
09-13-2012, 4:46 PM
Ernie the black levels are a function of color fill in Corel. select all the text and then left click the 2nd or third black % color swatch in the color bar.

Joe Sanchez
09-14-2012, 2:31 PM
I liked engraving on glass, until I started blasting them. So I offer my customer their choice, laser engraved or sandcarved. You can definitely notice a difference. But you have to charge accordingly. But what a nice world to live in when you can laser cut the masking with your laser, take it over to your blasting cabinet and finish it off.

Ernie,try playing around with the color-fills, adds a real nice touch to your work.

Have fun, that is the key.

David Rust
09-14-2012, 10:07 PM
Joe, what media and what pressure do you use for sand carving glasses? How deep do you go? Have you ever filled the blasted area with color? If so, what do you use for the color fill?

nancy barry
09-18-2012, 6:44 AM
I find that blasting the glass produces a crisper image than I was ever able to achieve with raster engraving. I have a Rayzist cabinet and use their mask as I can go deep if I choose. I use a fine grade of AL. Oxide as it produces the crispest edge...I go deep enough to catch my finger nail for most items... Sharpie marker followed with a UV sealer seems to work for non food items.

good luck!
nancyB

Dave Gates
09-18-2012, 10:09 AM
Use 180 grit for general sand blasting, either aluminum oxide or silicone carbide. We have silicone carbide. I've been blasting at ~30 psi for glass and higher for stone. Most drink-ware does not need to etched deep. If you go deeper, make sure to use a thicker mask, like 5 mil or higher. Most glass you only need a mask around 3 mil. I use spray paint from ACE Hardware/Lowes/Home Depot. You can use sand blasting to etch other items too.

Pics are etched(front and back) marble tablet for a customer and my flask.

241375241376241377

David Rust
09-18-2012, 10:32 PM
Dave,

What is the font size on the names? They appear very crisp! What do you think is the minimum CFM needed? I am hesitant to buy a big 220volt air compressor to try it out... Especially when my office/shop is small... The thought of a huge noisy air compressor in the corner is a hard sell to the wife.... I don't have an outside garage or shop to put it in so it would need to be quiet and preferably not too large... Mounting it outside is not an option with the snowy winters... Any thoughts?

Joe Sanchez
09-21-2012, 7:48 PM
David,

I tend to use around 30psi on glass. I blast with Aluminum Oxide. I have a blasting cabinet from Blast Media and I get my supplies from Iknonics up in Duluth, MN. I use a 4mil laser tape that you can pruchase from them or LaserBits (its green in color). I color fill with anything that will seep into the cut, shoe polish, paint, rub-n-buff. I really like the feel and the application of One Shot paint, easy to use and looks great. I have started blasting wine bottles to go with wine glasses and that seems to be doing well.