marble

[david ward]

what do I need to do to get a whiter effect on black marble. I have a 80 w trotec and have been using stiings: 100 power, 95 speed, and 1000 ppi. pictires look good just not white enough.

[Chuck Stone]

Try a second pass?

[walter hofmann]

try with less power first time marbel tends to chip tiny pieces if engrave with to much power on one run.
gretings
waltfl

[Keith Outten]

Spray your marble with Armor All and wipe off the excess before you laser engrave. If you search our archives you will find this little tip that I shared with everyone here several years ago.
.

[david ward]

i will try. thanks

[david ward]

the first one i tried was at less speed. it was terrible. then i sped it up to 95. picture turned out good ( even used armour all). still wasn't the white i expected. i will try less power. trotec settings are way off for marble. i know why they say it is a starting point but they don't furnish the marble.

[Bill Cunningham]

Are you running 'real' marble, or the granite the distributor calls marble?

[Chuck Stone]

Are you running 'real' marble, or the granite the distributor calls marble?

oo.. good point.

[david ward]

real marble

[david ward]

laser sketch. supposed to be absolute black.

[david ward]

lesson learned...laser sketch marble does not engrave worth a crap..got some marble tile from another distributor and it works great. grade of marble or so called marble makes a difference especially in the hip pocket.

[Bill Cunningham]

laser sketch. supposed to be absolute black.
It's granite... The best way to test it is to put a little acid (vinegar will work) on it. You will destroy the polished surface of 'marble. with any acid. I had someone eating an orange put their hand on a marble tile, the hand print was in it forever. Marble engraves 'white' and gets whiter with a second pass. Granite will engrave grey and a second pass will not get whiter and will ruin a photo on it. I find lasersketch very confusing. they seem to call everything marble except what they call granite. Don't get me wrong, the absolute black they sell is a 'very' high quality stone but it's not marble.. Zip into home depot and pick up a marble tile. doesn't matter what colour, it all etches white and give it a try.. Use about half the speed and full power, you do not need photograv or dithering methods with marble, you do with granite. Granite engraves with high speed, low power. Marble is just the opposite. Low speed and high power.

[Chuck Stone]

I had someone eating an orange put their hand on a marble tile, the hand print was in it forever.

I've seen you mention that before... have you ever tried taking it out with oxalic acid? If
you mix a bit with water and tin oxide (make a slurry) and rub that in with felt, it should
take out the hand print and seal the marble for good. It should also protect it from further
acid damage (to an extent..)

[Bill Cunningham]

I've seen you mention that before... have you ever tried taking it out with oxalic acid? If
you mix a bit with water and tin oxide (make a slurry) and rub that in with felt, it should
take out the hand print and seal the marble for good. It should also protect it from further
acid damage (to an extent..)

That was several years ago. I saved it for a job that had almost 100% coverage where the hand print had no effect on the finished results, but thanks for the tip Chuck. I'll save it for the next citrus sucker that touches my stuff without permission..ha.

[Chuck Stone]

That was several years ago. I saved it for a job that had almost 100% coverage where the hand print had no effect on the finished results,

Someone found it. It was in the most unlikely place.. where nobody
would ever put their hands
Somewhere there are people praying over that 'miracle in the marble'

[Bill Cunningham]

Ha.. never thought about that.. I could have sold it on EBay for a fortune..