Etching Into 18k Gold

[Tim Bateson]

Now I have always avoided jewelry engraving. A local Diamond Cutting & Jewelry design shop has convinced me to try to etch an image into a piece of 3x2 inch of solid 18k gold plate.

Disclaimers aside, has anyone done this and have any hints?

Attached is a sample of the image I cut into aluminum.
IMG_8240w.jpg

[Gary Hair]

of solid 18k gold plate.

Not sure it would work either way, but there would be a difference between solid and plate. Plate would reveal the base metal and solid wouldn't.

[Mark Sipes]

According to the clip on YouTube https://www.youtube.com/watch?v=OkGX8JAy-d4 A ceramic based material is applied... I assume it it Cermark does not tell the wattage but looks as good a stainless.. Won't the Fiber mark gold https://www.youtube.com/watch?v=hqqlyFSkyZo

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[Tim Bateson]

I plan to use the Fiber to etch into the gold. I'm sure I can, but worried the gold may warp as I etch it.

[Scott Shepherd]

Gold is also highly reflective. I'd be concerned about backscatter frying my tube.

[Mark Sipes]

As we tell the "new to engraving" several passes on low power is better than 100 power on your first attempt of a new material... spray the surface with a light coat of powder. Pam with baking flour comes to mind...




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[Mark Sipes]

Gold is also highly reflective. I'd be concerned about backscatter frying my tube.

Not to be a smart a** but rather to understand. How does the reflective surface cause the tube to be in jeopardy. Does the reflective beam traveling back through the lense and mirrors, overpower the beam leaving the tube and then frying the optics at the other end. I understand the lense is in a direct path of the scatter, just don't understand the tube part.

[Scott Shepherd]

Mark, I've been told that when it does happen, and I'm probably saying this wrong, it combines with the existing beam, heading backwards, and it can fry the tube. Even if it doesn't make it that far, backscatter can be bad for many things. I'm not suggesting you can't engrave gold, just that as a new user of the fiber, that might be a good question to ask the people that make your machine before throwing it in there and giving it a whirl. The risk might be zero, but in industrial lasers, shiny things like brass, aluminum, and copper were always very dangerous to deal with and those systems had some high dollar, serious protection to keep things like that from happening.

Just food for thought before someone fries a brand new $60,000 laser.

[Gary Hair]

spray the surface with a light coat of powder. Pam with baking flour comes to mind...

Please elaborate Mark, I've never heard of this before.

[Mark Sipes]

Well I just figured to cut down on the reflective surface a thin coating of dust would reduce the "scatter" so talked about as a damaging force to the tube and optics. When I am laying out acrylic awards I spray the surface so I can better see the red dot in placement of text and alignment. Clean up is a snap.

[Michael Hunter]

I thought the point of fiber was that the beam energy is absorbed by metal, rather than being reflected?

I can understand Tim's worry though - anything gold is by definition an expensive item and therefore potentially costly if anything goes wrong.

[Dan Hintz]

You will be very unlikely to make a dent/scratch in gold... even at the 1um wavelength of "fiber", gold is just too reflective. You really need something about half of the wavelength to get sufficient power into it.

[Scott Shepherd]

I thought the point of fiber was that the beam energy is absorbed by metal, rather than being reflected?

You'll still have the possibility of something highly reflective going back into the lens. The difference is that it's now a focused fiber beam going backwards into the system. Not something you'd want to happen on a brand new, high dollar machine.

[Michael Hunter]

You'll still have the possibility of something highly reflective going back into the lens.

If the metal absorbs the beam power, then it isn't reflected back into the optics.

But now Dan says that gold *is* reflective at fiber wavelengths.


I'm confused here - Trotec specifically mention gold in the list of materials that their fiber laser will engrave and Epilog claim their fibre will mark "almost any metal".
So which metals are truly suitable for fiber engraving?

[Dan Hintz]

If the metal absorbs the beam power, then it isn't reflected back into the optics.

But now Dan says that gold *is* reflective at fiber wavelengths.

To be clear... gold is nearly 100% reflective at 1um wavelengths (most of what people have). You don't get into real absorption amounts until you're below about 600nm. Gold has a nice little absorption peak around the 530-540nm mark, so a green laser at 532nm is often the best choice. The problem is, green lasers aren't nearly as powerful as your typical 1um fiber (dollar for dollar), but the absorption is so strong there you don't need to be that powerful.

I can't say I've ever tried gold with a 1um fiber... never any call for it. But feel free to try and let me know how slow you have to go before you start to make a dent.