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View Full Version : Anyone every try the spray on powder coating for laser?



Tom Delaney
08-25-2008, 6:46 PM
I've got an opportunity to pick up a small powder coat system (spray and bake). The people selling it are telling me it is a polyester based powder. Has anyone ever given it a shot? :confused:

Belinda Barfield
08-25-2008, 6:54 PM
Tom, I was just thinking of this same thing myself this week. Now y'all don't all laugh at one time. My concern is that I would get distortion of the letter or image since heat causes the powder to bond and the radiation of heat away from the point of laser strike would bond excess powder. Am I completely crazy? If this works just think of the variety of colors to choose from. . . and what about multicolor images?

Frank Corker
08-25-2008, 7:05 PM
Okay, who's got access to this stuff and where are the test results?????

Bruce Volden
08-25-2008, 7:50 PM
Tom

I helped a good friend of mine start up a powder coating business 10+ years ago and he's still going strong!! I helped build his oven 7'H X 21"D X9'W (big huh). I lasered through quite a few items and it does laser~there are stipulating factors.

1. Depending on the thickness of the powder application, the lasering can be a pain! Too thick means multiple passes as poly is a plastic and if you try to get through it in one "burn" you WILL lose detail.

2. Depending on the substrate (regular steel vs. stainless for example) why bother as it sometimes won't "pop". Lettering hard to see on a dark color with "plain" steel.

The items I tried to turn a buck on were mostly flat items used in signage.

Powder coating is very hard and durable and also available in ANY color you can think of including metallics and pearls etc.... It also comes in other forms besides polyesther, epoxy comes to mind.

Bruce

Lee DeRaud
08-25-2008, 7:51 PM
Not sure what people are trying to do here...is it:
1. spraying on the powder and using the laser to bond it or
2. spraying on the powder, baking it, and then using the laser to remove it?

#1 is giving me flashbacks to the last time I had a laser printer toner cartridge break. :eek:

Larry Bratton
08-25-2008, 8:20 PM
I'm with you Lee...but...are we on to something here ?, I think Belinda is thinking you could laser the powder and bond to the substrate in color..right? Not knowing much about powder coating I can't comment very much. It sounds interesting though.

Mike Null
08-25-2008, 8:37 PM
Wish I had good news here but I tried applying the powder coat with a brush then lasering it to simulate the baking required. It didn't work. I have a nearly full jar of black powder with no apparent use.

Michael Wintermute
08-25-2008, 8:46 PM
I have a guy that powder coats mostly motorcycle/bike parts and he coated a heat shield first with a red similar to molten steel and then top coated it with black. I cut through the black leaving the red(it had people cautious about touching it). It took a lot of playing with the settings to get it to look good. The next part we tried to do needed different settings(and he has been painting/powder coating pro for 15+ years so it saw not the easy to duplicate). It looks great as lazing it will leave a gloss finish and a crisp edge when you get the settings right.
Still see the 'cycle from time to time but never took a picture.
Settings too long ago to find/remember.
Mike

Belinda Barfield
08-26-2008, 8:00 AM
I'm with you Lee...but...are we on to something here ?, I think Belinda is thinking you could laser the powder and bond to the substrate in color..right? Not knowing much about powder coating I can't comment very much. It sounds interesting though.

Larry, you are correct. I've been running this around in my head for about a month now. We had the opportunity to purchase a used "oven" for powder coating, thermoforming, etc. At the same time we were approached about powder coating some items. We opted out on getting into powder coating at this time, but it got me thinking.

I mark stainless placards for a company whose logo is glossy red and blue. They accept the black Cermark, but really want the logo in color. With all of the powder coat colors our ability to mark in color would greatly increase.

Brian Robison
08-26-2008, 9:11 AM
I did several signs for Honda Corp for some machines on the line. They needed them to hold up to coolant and chips.
We went with aluminum T6061, powder coated, then I used Thermark to get a black mark. It took a long time to run them but they turned out quite nice. I don't think I shot a picture, doh.

Belinda Barfield
08-26-2008, 10:00 AM
I did several signs for Honda Corp for some machines on the line. They needed them to hold up to coolant and chips.
We went with aluminum T6061, powder coated, then I used Thermark to get a black mark. It took a long time to run them but they turned out quite nice. I don't think I shot a picture, doh.

Do I understand you correctly, Brian, that you used Thermark on top of the powder coated finish?

Brian Robison
08-26-2008, 11:41 AM
No, I lasered off the powder coating and then lasered the bare aluminum (with Thermark).

Gary Hair
08-26-2008, 2:03 PM
It IS possible to laser powder coating, I have done a bit of experimenting with it. I bought black, white and yellow from Harbor Freight - about $4.00 each. My biggest problem was getting the powder to flow evenly on any of the surfaces I wanted to test. You can't simply brush it on, it's too thin. The best results were to raster test in wood, fill with powder and laser again. I was able to get pretty decent results with the black but haven't had the time to try yellow or white. I don't have my notes handy, but I think I used about 40% speed and 30% power for my 30 watt, 80ips laser - so about 32ips and 9 watts for a starting point.

I would like to try a powder coating gun to apply the powder to a piece of metal and then laser, but I haven't found the time, and the gun, to do the testing. It took me about 3 hours to get to a point where it was sticking to the wood.

Gary

Larry Bratton
08-26-2008, 7:16 PM
Larry, you are correct. I've been running this around in my head for about a month now. We had the opportunity to purchase a used "oven" for powder coating, thermoforming, etc. At the same time we were approached about powder coating some items. We opted out on getting into powder coating at this time, but it got me thinking.

I mark stainless placards for a company whose logo is glossy red and blue. They accept the black Cermark, but really want the logo in color. With all of the powder coat colors our ability to mark in color would greatly increase.
I reckon CLTT would work on it. I have put it on aluminum and it worked fine, however the aluminum was painted. It works on most everything with the right paper.

Phil Salvati
08-26-2008, 7:34 PM
I laser quite a bit of Motorcycle parts. Chrome, Anodized and Powder coat.

We have had good luck vectoring designs in powder coated parts and paint filling them. Rastering designs on domed objects has been difficult to get done, not impossible, but not in a money making time frame.

Making sure the substrate is not pot metal will make your day easier. Pot metal cannot take the 400 degree heat the PC needs to cure. The end result will be dimpled like an orange peel effect.

We have been working lately on two color process. There are powders than can be baked twice, as well as clear coated. Our first hurdle is two and three coat thicknesses. When we master that, I can post some pics.

Phil

Eric Allen
08-27-2008, 4:12 PM
Gary, it sounds like you had some interesting results. I tried using it on metal, but I think it vaporized every time. Might just have been hitting it too hard, I think my application required vector thin lines and that's always a hoot to calculate the settings for when it comes to marking:) I was just looking for another option to cermark's single color, thought it might work out but hadn't had any luck.

Richard Rumancik
08-27-2008, 4:27 PM
Wow! Lee is not the only one who is getting confused. I think we have three or more threads going on here.

Tom wants info about "small shop" powder coating. He did not say what he plans to do after to the powder coat (if anything.)

Tom; you might find some useful info at the Caswell plating website. Also, here is a "cautionary" note I found in my file: www.saltmine.org.uk/kgb/kits.html
The same author has some info on powder coat for motorcycles which may be of interest so you know what is involved: http://my.execpc.com/~davewrit/Powder.html

Tom, if you just want to do small flat plates etc then I think it is probably feasible to do it in the home shop. Beyond that it gets complicated.

Belinda wants to laser-bond powder coat material to a flat surface. The problem with this is keeping the powder in place while you try to bond it with the laser. The air assist, exhaust, and just the velocity of the carriage will blow the powder all over the place. Mike says he did not have success in his tests. I suspect that bonding to metal may be problematic as you have to raise the metal temperature very high very rapidly to get a bond.

I was experimenting with this concept some time ago as well for plastic; seemed to me that you need a liquid "carrier" to basically suspend the powder coat powder into a mixture that can be painted on or airbrushed on, then dried and laser-bonded. Similar to Cermark application. But so far I have not come up with the magic formula . . . On the other hand, I think TherMark has also been working on it but I have not yet seen any products on the market yet. On their website they say Color on Metal and Color on Plastics is "coming soon!". But they have said this for a few years so they have not come up with a product yet. They do have a "black on plastic" solution but they also state: "Due to the extremely wide variety in plastic materials, marking plastic with TherMark laser marking materials can be a hit or miss proposition."

If you restrict powder coat use to filling text or graphics with powder, then you may be able to heat cure it with the laser. The recessed text will hold the powder from blowing around (within reason.) Gary says he had acceptable results.

This is similar to what the fellow from Smoke-Wood does.
http://www.smoke-wood.com/SM-wd-21.HTML
I don't know what his material is but some people have suggested it is a powder coat powder.

Michael is applying 2 layers of powder coat and lasering through the top layer. Apparently it takes some trial and error to get the settings right. Phil is using one layer of powder coat, rastering, then paint filling.

Brian is cutting through powder coat then darkening the underlying material with Thermark.

Lots of interesting ideas and experiments going on. Seems like laser users tend to be always trying new angles. (But maybe it would be better if we kept the threads separate . . . )

Tom, why don't you tell us what YOU wanted to do with the powder coated parts?

Frank Corker
08-27-2008, 4:55 PM
Hey Belinda, I was with you. I was hoping that this was going to lead to another method of engraving a coating onto metal and being able to use different colours. I'm glad at least one person tried it because the tests could have proved to be something special. Now as far as I'm concerned I would like someone to test the powders that they use for enamelling work and see if the laser can do something on that.

Mike Null
08-27-2008, 5:02 PM
In my pre-retirement experience we used electrostatically charged paint on steel then it went right to the bake ovens on overhead conveyors.

What I was hoping to do was find a way to colorfill wood and eliminate the bleeding problem (capillary action) of liquid paints. I think that you can't get adequate, sustained high enough temperature to duplicate the baking process using the laser. Wood is my issue. I don't have a problem with colorfill on other materials.

As far as lasering powder coated metals they laser beautifully though I use two passes to clean them up. Powder coating is not uniformly thick.

Belinda Barfield
08-27-2008, 5:07 PM
Richard,

I see your point and I apologize for veering off in a direction other than what Tom obviously intended, although I didn't realize we were headed in different directions until I read his post again. I was confused by the title line portion "powder coating for laser". Sorry guys, didn't mean to hijack. It was completely unintentional.

Rodne Gold
08-28-2008, 1:55 AM
Why dont you use a wax on wood , like crayolas , no capilliary action if you mask and if the wood is sealed prior to lasering you dont need to mask at all as you can easily clean off the residue.
We warm the crayolas in hot water and "colour in"

Mike Null
08-28-2008, 5:15 AM
Rodney

Interesting idea. I'll give it a try.

Clyde Baumwell
08-28-2008, 7:02 AM
I followed this thread - it was all in the same ballpark - kinda. Has anyone had experience or tried laser engraving low temperature glazes found in the ceramic/pottery industry. Lots of colors and might offer the results that some of you have been discussing.

Clyde

Gary Hair
08-28-2008, 12:33 PM
Gary, it sounds like you had some interesting results. I tried using it on metal, but I think it vaporized every time. Might just have been hitting it too hard, I think my application required vector thin lines and that's always a hoot to calculate the settings for when it comes to marking:) I was just looking for another option to cermark's single color, thought it might work out but hadn't had any luck.

Eric,
My first attempts vaporized the powder as well. It's very tricky to find the best speed/power settings and it will vary with each laser, substrate, powder, temp, humidity, etc.

I ended up creating a grid of 1/4" squares that I rastered into 1/4" mdf. I filled them all with black powder paint and started lasering. I don't have the piece in front of me, but I started with 100% P and 100% S and decreased the S by 10% in the first row, then started the second row with 90% P and 100% S and again decreased the S by 10% each box. I ended up with a bunch of squares that had nothing, it vaporized the powder, and a few that had actually fused to the wood. I ran the test again with the S and P settings from those grids and reduced by 1% this time.

This is the same process I used to find the optimal Cermark settings for a large stainless steel job I did a while back. I had over 1,000 plates to laser and I really wanted to optimise the job. I ended up saving about 45 seconds per plate by spending 10 minutes with my grid work. That 10 minutes saved me almost 14 hours on the 1,100 plates - time well spent!

Thanks Sean Weir at Ferro for that advice.

Gary

Lee DeRaud
08-28-2008, 7:07 PM
I followed this thread - it was all in the same ballpark - kinda. Has anyone had experience or tried laser engraving low temperature glazes found in the ceramic/pottery industry. Lots of colors and might offer the results that some of you have been discussing.Sounds like a fun experiment if the glazes are available in small quantities...got any source links?

Bill Cunningham
08-28-2008, 8:38 PM
I have used ordinary black photocopy toner brushed into the engraving. The oil and residue in the letters, tends to make it stick, and it's well inside and away from 'rubbing fingers' And no, it does not come out.. As with any brush on stuff, you must either use mask, or make sure the part is well finished, and no grain to trap the toner powder.. This will 'not' work on Oak, unless you have enough coats of sealer to fill the grain before brushing in the toner..
But it's nice and black, and it does not bleed

Eric Allen
08-29-2008, 11:01 AM
Eric,
My first attempts vaporized the powder as well. It's very tricky to find the best speed/power settings and it will vary with each laser, substrate, powder, temp, humidity, etc.

I ended up creating a grid of 1/4" squares that I rastered into 1/4" mdf. I filled them all with black powder paint and started lasering. I don't have the piece in front of me, but I started with 100% P and 100% S and decreased the S by 10% in the first row, then started the second row with 90% P and 100% S and again decreased the S by 10% each box. I ended up with a bunch of squares that had nothing, it vaporized the powder, and a few that had actually fused to the wood. I ran the test again with the S and P settings from those grids and reduced by 1% this time.

This is the same process I used to find the optimal Cermark settings for a large stainless steel job I did a while back. I had over 1,000 plates to laser and I really wanted to optimise the job. I ended up saving about 45 seconds per plate by spending 10 minutes with my grid work. That 10 minutes saved me almost 14 hours on the 1,100 plates - time well spent!

Thanks Sean Weir at Ferro for that advice.

Gary

Yeah, they really are top notch at Ferro. I was horrified at the price, until the first time I needed some major help on a project. They go waaaaay out to help their customers, so it's completely worth it. If I can find a day with nothing to do (laughing hysterically) I should break out my electrostatic gun and give this a wing, probably answer a raft of questions. They're not very expensive, I got mine when Harbor Freight had a sale going, cost $50 for the gun/power source. I really think there's a lot of potential uses for this material for what we do, if those of us with the stuff can all take a chunk of the work and figure them out. Kudos on being the first! (That I've seen, anyway:) )

Ed Peters
08-29-2008, 12:49 PM
I manage a powder coating operation as part of my day job and some of you folks have me scratching my head. If you want a color rich logo or text, why not just screen print it on? Also, read somewhere in this thread that 6061 aluminum was chosen to stand up to the cololant and chips? We run 5052 (a less costly alloy) in our machining centers and lasers all day with no ill effects from coolant and chips. Not sure where that was heading. Let me also suggest that HF is not the best place in the world to acquire powder. Many manufacturers will supply you with 2lb samples of their products for free and 2lbs will go a long way. Tiger Drylac comes to mind, Spraylat, Protech etc.

Ed

Richard Rumancik
08-29-2008, 10:24 PM
I manage a powder coating operation as part of my day job and some of you folks have me scratching my head. If you want a color rich logo or text, why not just screen print it on? . . .


Well, if your main tool is a hammer every problem tends to look like a nail . . .

I guess for most of us our main tool is a laser and although many on the forum dabble in other areas (CNC routing, vinyl, signmaking, sublimation, etc etc) the thing that is common to most everyone here is that we do laser marking/cutting/engraving. Very few members are screenprinters and it is not simple to set up a small screenprinting operation to do a few items nor is it economical. So what we would like to be able to do is to fuse colored material (such as powder coat materials) to a substrate (wood, plastic, or metal) and be able to make a few dollars even if the quantity is low. And of course to many of us, it just looks like a problem that the laser should be able to handle . . .

Gary Hair
09-03-2008, 11:48 AM
Let me also suggest that HF is not the best place in the world to acquire powder.

Maybe not when you "manage a powder coating operation", but when you are a laser engraving shop and HF is less than 2 miles away and the powder cost is about $5.00, it is the best source for me. If I was doing production powder coating I would buy the best application system and the best powder that I could cost-effectively use, until then I'll stick with HF and my laser.

Thanks,
Gary