Laser marking on graphite

[Adam McEwen]

I'm looking for someone who can laser mark on graphite (a smooth, sanded surface), either with a YAG laser or a CO2. I'm talking about marking the graphite (ie: burning it black) rather than engraving or cutting into it.
I've had good results working with a company using a YAG, but the bed size is too small for this next project. I need to laser onto a panel 39" x 52", so the bed needs to be able to accept something that big. A CO2 laser on graphite doesn't burn as black, but it's good enough for my purposes, and it has the advantage of being able to run from a tiff, rather than a vector file.

Does anyone have experience with this? I'm looking for someone in the New York area who would be interested in a job lasering one of these panels.

Thanks!

Adam McEwen

[Dan Hintz]

I've never done graphite before... are we talking pure mineral or the clay-based stuff used in pencil lead?

If pure mineral, YAG is going to give you the better mark without question, but YAG systems will be harder to find than CO2, particularly for the bed size you're after. For New York-based CO2 outfits, check out our Friends of the Creek listing (red button up top)... Dee and Steve are two I can think of off f the top of my head in the NY area. If they can't help (and you don't mind a bit of travel or shipping), I can help you out.

[Lee DeRaud]

I've never done graphite before... are we talking pure mineral or the clay-based stuff used in pencil lead?

Sounds more like he's talking about carbon-fiber panels...
I'll be interested to see the answers myself as I'm pondering making some CF Strat pickguards.

[Scott Shepherd]

Dan, you did see the panel size of 39" x 52", didn't you? I don't think Dee, Steve, you, or me can do that one

[Dan Hintz]

I was just going to fold it to fit Yeah, noticed the size after reading Lee's post...

[Jack Harper]

I played around with some graphite and found that it does make a mark, just not a high contrast mark. I decided to do an experiment and cut some acrylic placed directly on top of the graphite block. I was amazed to see zero back flash on the acyclic, it didn't even have smoke damage. It appears that graphite absorbs laser energy very well. My next thought was to cover my table with it as a cutting surface, but found covering 60 sq feet was going to be quite expensive. I even thought about water-jetting the sheet into a cutting grid but I suspect it would become too fragile.

[Joe De Medeiros]

I played around with some graphite and found that it does make a mark, just not a high contrast mark. I decided to do an experiment and cut some acrylic placed directly on top of the graphite block. I was amazed to see zero back flash on the acyclic, it didn't even have smoke damage. It appears that graphite absorbs laser energy very well. My next thought was to cover my table with it as a cutting surface, but found covering 60 sq feet was going to be quite expensive. I even thought about water-jetting the sheet into a cutting grid but I suspect it would become too fragile.

I'm not surprised, we use graphite marvers to shape hot glass, and it seems to hold up to very high temperatures, the other neat thing is molten glass will not stick to it, so lots of push molds for glass are made from it.

[Dan Hintz]

Jack,

Any suggestions on where to get smaller slabs, say 2'x2'?

[Jack Harper]

Jack,

Any suggestions on where to get smaller slabs, say 2'x2'?

I don't remember where I found it, but I found it in a large selection of sizes. I just googled to find it though.

[Joe De Medeiros]

Jack,

Any suggestions on where to get smaller slabs, say 2'x2'?

Dan I have ordered smaller pieces and marble molds from here graphitesupplies.com but it's not cheap, A 20"x24" 1" thick is $277.

[Dan Hintz]

Thanks, Joe, I'll check them out...