Masking Granite tiles

[Tom Cullen]

Has anyone ever tried to mask a granite tile then engrave it with text and fill it in with paint? I tried it yesterday with regular blue masking tape and acrylic spray paint ( white) but found that I had to run it twice and up the power and speed from what I would normaly do on a granite tile using a 30 watt laser. I also got a lot of bleed from the paint...think I may have sprayed too much and did not give it time to dry. What have others done? I was trying to make the font on the tile stand out more. what would be the best type of masking material to use? and what would be the best paint to use for out doors?

Tom

[mike klein]

Tom,

What I do on wood, corian and other materials is after engravig, spray the surface with Krylon Cyrstal Clear. This will seal up the engraving and you won't have any bleed thru, least I haven't yet. For tape, I purchased some masking from Laserbits some time ago and that has been working great. Again, for outdoor use my thoughts would be to use the Krylon product, others may have different opinions.

Mike

[art baylor]

Tom:

I have found that some times you get blue painters tape that just doesn't stick well enough to prevent bleed under the edges. I don't know if it's old or why that is, but some is definatly better than others even in the premium brands. You might try a new roll (differnt store, different brand) and lighter coats with recommended drying time. Mike's ideas are very good too.

Art

Art

[Rodne Gold]

You are confusing 2 methods of engraving granite.
The traditional method is to use low power and high speed anf the laser merely leaches the color out of the stone .
To fill , you need to actually fracture the stone to accept a colour and this will require a LOT more power as you are no longer vaporising colour , you are trying to thermally shock the stone to promote it fracturing due to differential expansion rates of substances the stone is made of.
A better option to do this is not to use the laser to fracture the stone but merely to vaporise a resist and then to sandblast the stone and colour fill.
Polyester vinyl (laser friendly) would be a very good resist and automotiver ducos in spray cans is a very good paint to use. Spray light coats , wait for em to dry , overspray em , spray perprendicular to the stone. Papar based resists will give you problems as they will absorb the paint and solvent and this will destroy the adhesive etc.