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View Full Version : Of course I can engrave it. :)



John Noell
01-24-2016, 6:04 PM
We have a large black pearl ($$$) farm in town. After the pearls are harvested they polish and cut the shells into shapes. Then they frequently ask me to engrave them. After years of trying to educate them about what can and cannot be engraved (and come out looking good), this is what they sent me today. :) (They also asked if these were okay as is - or did I need "artwork." The average size is 7KBs.)

Clark Pace
01-24-2016, 6:29 PM
Pearls are tiny right. So nay of those images would scale down to decent resolution. Question is can the laser achieve the detail needed on that scale.

David Somers
01-24-2016, 7:07 PM
John,

You are doing the mother of pearl layer from inside the shell right? Not the pearl itself? Gads that would be small if you were!!!

Send us photos of all this when you are done engraving it! OK John!!!!???? <grin> Artwork!!! Pfft! Who needs artwork! You did get a color laser right? Mine is only Black and White so I would have trouble doing anything but the flock of birds. With a color laser you are sitting pretty of course!!!!

<grin>

Dave

John Noell
01-24-2016, 9:08 PM
Well my laser is read and white so that means it is a color laser, right? And we are engraving the polished outside of the shell. They are quite pretty and have varied colors, moistly grey-green but some our quite golden. (I have attached one with gold Rub'n'buff fill.)

At the prices these pearls command, they are not about to let me anywhere near them, with anything, much less a laser!

David Somers
01-25-2016, 1:36 AM
Very pretty John!! I am helping a friend with some Mother of Pearl Inlay for guitar pick guards right now. Pretty stuff to work with. Miserable to try and scan to make a mask and path with in Corel or Illustrator though. Too many subtle colors that the scanner picks up. Better off tracing it by hand most of the time. But pretty stuff.

I like the grass matt as a backdrop in your photo too. Is that a Kuta matt or a local make? I always enjoyed seeing a fine matt made in Samoa. An amazingly simple but demanding process.

Cheers to you two!!

Dave

gary l roberts
01-25-2016, 8:02 AM
I didn't think you could cut or engrave mother of pear because of refraction of the beam. Did you hand cut the shape then engrave with the laser? Or have you put your children to work with tiny tools (lol)? Power setting, speeds?

John Noell
01-25-2016, 4:20 PM
Cut? No! Engrave? Absolutely! However, much like glass, the laser beam causes the polished outer layer to shatter and (with air assist) blow away. The under layer is (mostly) raw calcium carbonate (white). I usually use about 300mm/s and 35% to engrave (scan) and a bit lower power to vector (for fine lines). The local pearl farm has a woman who polishes the raw shells and then cuts them to shape. That's when they come to me. I have tried polishing some but you need a wet polisher and the dust is nasty stuff, so I let the pearl farm do it these days.

Bill Carruthers
01-25-2016, 4:23 PM
Hi John
We are not only Pacific neighbours but I also do lots of pearl shell engraving as we produce many black pearls in our northern group islands. I'll try and find a pic or two of something I've done but am on a different computer to normal so don't have access to good ones. The black pearl shell engraves easily to a whiteish finish and is regularly used here for name tags ,medallions,etc.. It is possible to "cut" the shell as well but it takes about 3 or 4 passes with a 100 watt at about 3mm/sec, and the finish is messy, so it's much quicker and easier to use normal grinding and cutting equipment if you need a specific size or shape.
It's also possible to engrave on the actual pearls and I regularly put initials and so forth on black pearls for customers- photo below is not too clear(lousy camera) but is done on a 8mm pearl.
330251330252330253

John Noell
01-25-2016, 8:30 PM
Nice work Bill! We've done many hundreds of the round medallions for awards. And yeah, I've "cut" shell but it's more like blasting my way through. :) I could not get as much depth with the 45 watt Epilog, but now, using 90% power at 8mm with an 80 watt EFR tube goes pretty deep.

What settings are you using? (And do you have the hibiscus font? Lot of hibiscus variations.)