Laser Powder Coat Graphics

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#1

I am waiting for my Glowforge like so many others. But while i am waiting I have been keeping track of what others are doing and taking notes so when I get my laser I can start experimenting with various materials and processes. To extend the utility of the Glowforge there are many unusual things people are doing. A Glowforge can’t etch stainless steel but I have been aware that people are putting graphics on stainless with a laser ink. You paint on the ink, etch on the surface. Then wash off the excess ink and where the laser printed the graphics it is permanently marked. Laser ink is very expensive so I noticed people are printing with moly dry lubricant… From You Tube videos I can see that this process does work. Then I thought about powder coating which is a thick glossy coating that is heat cured. Powder coating comes in many colors so I thought it would be great to be able to do graphics and text in color to any substrate. The powder coating process is very involved because you need to clean your part, Then apply the powder with an electrostatic paint gun. The trouble is that if you put this part in the laser for etching the laser air that keeps the head clean will blow off all the powder. But after surfing the internet I discovered there is a liquid carrier substance available. You can mix the powder with the liquid and it will become liquid paint which then can be sprayed or painted on the substrate. And after drying it can be put in the laser and etched. After which the laser graphics will be permanent and the excess can be washed off leaving a high gloss graphic or text on the surface. Also, because no electrostatic charge is necessary you can do this on wood or plastic, not just metal. This sounds fantastic. I can’t experiment until I get my glowforge. But I was wondering if anyone has tried this liquid powder coating with their laser.


#2

I have lasered powder coat in my K40. It does a good job of vaporizing the powder coat. I have been powder coating aluminum samples and curing them in an oven the traditional way. The results are pretty good, although with this cheap unit, I’m sure the results are only a quarter as good as they will be when I get the Glowforge and can do vector engraves.

If you make a mistake with the powder coat, you can wipe the cured powder coat off with acetone. since the laser doesn’t touch the metal, you can simply start over again.

I have the Eastwood Hotcoat gun. Harbor freight makes a knock off. I haven’t used it, but I can tell you there isn’t a ton of “Magic” in the Eastwood system. HF’s powder is cheap too. I bought 2 bottles of it yesterday. $6 each.

I would think that using the laser to cure the powder coat would be a bust. The material needs to come up to temperature as well as the coating, in the 400° range, and the coating needs a little time in the heat to crosslink. I’m not convinced the laser is going to have the capabilities to meet those requirements.

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#3

Not to mention that the air assist would blow it all off.


#4

Air assist? The K40 don’t have one. Just Kidding. I added one.


#5

What is this carrier? I’d be willing to give it try.

Powder coat is pretty cheap so if the carrier isn’t crazy expensive it wouldn’t be a big deal to run a quick test and maybe it’ll be cool.


#6

Here’s one.

I have bought from this company, but not this product.


#7

I have all the gear to do a test, But I don’t want powder coat dust all inside this unit.


#8

Thanks. I’ll order some to see how it works.


#9

I thought we have control to turn it off?


#10

As of now in the UI. Nope.


#11

Oh, interesting. I could have sworn I read somebody’s post that they tested some materials with it off. Maybe you and that person use different software revs.


#12

Doubt it. Unless that person was a beta user.


#13

He was. Looks like it was Dan.


#14

I did some more research on using liquid powder coat with a laser. There are some people experimenting with this plus many big companies. I found a company that is powder coating MDS and using a laser to give it a wood grain effect for doors and windows. Another website said you need to use very low power to just get the powder coat to flow and attach to the substrate. Then you can remove the excess and cure the piece in an oven or with a heat gun. Also there is a You Tube video of a guy that powder coats wheels the conventional way, but he also powder coats a plastic center plug to match using a heat gun to cure it. So I am excited thinking the process could work. Use the liquid powder coat on your part, Let it dry. Put it in your laser to add some text or graphics. Remove the excess powder coat. Then cure the part in a 400 deg oven or with a heat gun. You should have great looking powder coat graphics in any color. The website said you need very low power to just get the powder coat to flow and you might have to defocus the laser to spread the heat and not destroy the part.


#15

Many people have mentioned that if you did powder coating with a laser the air assist would blow it off. But that’s what my posts are trying to tell you…with liquid powder coat you have a liquid carrier that can be painted on and dries like paint. so the air assist can’t blow it off.


#16

Isn’t liquid powder coat, paint? Just heat cured paint? Liquid carrier for solid pigments seems to be the definition of paint (not being snarky here). I guess what is the difference from this versus say Stove paint?


#17

The liquid carrier for powder coat paint is a special carrier liquid . You
mix your dry powder with this carrier and it becomes possible to put it on
the part without a powder coat gun. You don’t need the 15KV electrostatic
charge to adhere the powder. It is water based. So you mix your color and
paint it on the substrate. When it is dry the laser air assist will not
blow it away so you can use the laser to apply graphics or text to your
part. Then remove the excess paint and finish the cure in an oven or with
a heat gun. It is not regular high temperature paint. It is a special
product to enable you to do powder coating without the gun and on things
other than metal, like wood or mdf… I did research on the internet and
found this information. Looking forward to trying it out when I get my
Glowforge.


#18

I’m too lazy to go read, so how do you remove the excess paint? And can you reuse it?


#19

It looks like you mix the carrier and powder coat, but I haven’t found how long the mix is good for. After spraying, the excess can be easily wiped away with a rag or whatever. I would guess it might be little messy trying to get it off of porous wood though. Cool stuff.


#20

That brings in a neat way to work with metals by lasering of the “not to be coated” sections sharp and cleanly.