Color never faded…after several years, it finally got a bit too weak from the wind I think…(wind and vibration from the car I assume and snapped when I was removing it to put on my new year sticker…
I have two Universal lasers. And yes, it’s all Rowmark engravers plastic
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Thank you @jkopel. I searched this thread because I am interested in cutting gold and silver leaf. I buy it pre-applied to transfer paper. It seems to be applied to the paper with a super thin layer of wax to keep it from flying all over the place when using it in the food industry. It releases from the paper when the gold side is applied to a slightly damp/sticky surface (like icing 
) If I can cut filigree/designs/monograms through the leaf and it’s transfer paper, it opens a lot of new doors for direct design application onto edibles and cakes, etc. I’m currently hand cutting those tiny bits of tissue paper. Whew. I don’t have experience in laser cutting. Can anyone tell me if gold/silver leaf in it’s .2 micron thickness, applied to transfer paper, could be cut safely with the Glowforge? I’ve heard metals are out, but then I’ve heard leaf may be ok. Will the CO2 laser strictly not cut metal of any thickness? If it can etch metal, could it cut through a .2 micron metal? What is it about the metal that doesn’t allow the CO2 laser to cut through it?
@jkopel, @dan, Can I send you some gold leaf or silver leaf to test?
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by default I want to say no because that is what we have been told about metals. That being said its so thin I don’t know what to tell you except maybe send a small sample to someone on the board here with a k40 if they are willing to do a test
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There is stuff out there called Rowmark engraving acrylic that has a surface that looks as though it is real thin metal and cuts just fine, I await the practical test of your query with interest.
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As I understand it, just answering why metal is different for lasers. Plastic and wood are organic compounds. Carbon based materials absorb energy in a very different manner than metals. Basically they are the fuel for the heat of the laser. They burn and vaporize. Metals generally reflect and then reflect different for different wave lengths of energy. That is why metal cutting lasers are made with different gases that have different wavelengths. Also power fits in here. Metals can enhance oxygen for a fire, like the finely ground aluminum and iron in thermite burn. Marking metal is bonding another substance to the surface of the metal, like Cermark. Aluminum is marked when it is anodized, the surface of the aluminum oxidized in a thicker layer along with other elements to provide color. The surface oxidation is marked and not the underlying aluminum.
Still awaiting a laser users answer on gold leaf. But what I read it is problematic.
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If they dont get back to you…I would be glad to try it for you…I have a 35 wt laser so if I can cut it, most assured the Glowforge could.
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I’ve got a 30W (actual, 40W peak) and a 60W if it turns out Stephanie’s 35W doesn’t work. The GF Pro is 45W and the basic is 40. I can tune the 60’s power to try at either of the GF levels.
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Here’s an off the wall idea: you could flip the gold leaf bonded to transfer paper over in the laser and use the laser to burn away the transfer paper on the back, wherever you want the design to show through. (Might have to invert the image). If it all hangs together, you could put that on the frosting if the gold will stick but the paper would not stick. Maybe you could rub something slick on the paper before lasering so it wouldn’t stick to the frosting.
This would only work with gold leaf that is bonded to transfer paper. The inexpensive composition gold leaf you get in the craft stores just has loose tissue between each layer of leaf.
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Um no. Metals burn just fine on their own, metals can only be oxidizers if they are already oxidized themselves and something comes along with a really strong oxygen avidity to tear that oxygen off. Aluminum does burn quite happily and is a bitch to put out when it does. Magnesium is even worse when burning. Rusting is iron oxidizing quite happily, but just really slowly, try pure iron in an high-oxygen environment and you can witness iron burn spectacularly. The iron in thermite is iron oxide, and when the aluminum burns (classically sparked by a Mg wick) it is so oxygen avid that it tears the oxygen out of iron oxide to burn itself, which generates enough heat that the iron meals and welds or burns through other metals (depending on the mixture). Other metals are even more oxygen avid (potassium, sodium, etc) and can burn just by coming in contact with oxygen, which is why you store them in oils.
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An interesting concept @cynd11!
Thanks for the correction. I should have left it to the experts. Trying to make the connection with the oxidation needed and failing to understand the metals do act as the fuel. Class D fires.
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After some research, thickness doesn’t matter, gold cannot be cut with a lower under 100wt laser…
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Bummer. Thank you @smcgathyfay. It was definitely worth a discussion. Where were you finally able to find a definitive answer?
I will call my Universal laser expert guy in the morning, but from what I’ve found online, its a no go.
I’m really jonesing for a 130W one 
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I wish I had better news, but you’re fighting the thermal conductivity of the metal, plus the metal itself reflects the IR light, so it’s unlikely to work (and not something we’d recommend testing).
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We had a Trotec at my previous school and we also had a rotary - we could ‘engrave’ water bottles, but now I am thinking that it was maybe just removing the layer of paint from the bottle (as people have said here). Wondering if that would work on the Glowforge with a colored water bottle… but as far as I know, they do not have the option to do anything round yet, correct?
you also have the issue of the water bottle not being more than 2" thick, which pretty much rules them all out.
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