Seeking advice on applying clear powder coat

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Righty Tighty

Righty Tighty

Blame it on the dog
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Howdy FABO, I've been trying to learn how to powder coat lately. I've had some pretty good success with opaque colors on sand blasted parts, but this last project gave me fits.

My Pops turns pens as a hobby, and usually he applies CA glue as a durable and glossy clear coat, but it's tedious and time consuming. He asked if I could do a clear powder coat on his latest batch, so I gave it a shot.

The parts were polished brass .308 cartridges, cleaned with acetone prior to applying the powder. The powder went on fine, and the first coat flowed & cured nicely. However, it was hardly noticeable that there was a clear coat on them at all -- just looked slightly more glossy than before. I let them cool, applied a second coat, and all but one (9 total) ended up with terrible orange peel.

Does anyone have any tips on applying multiple coats and/or how to avoid orange peel?

I didn't take pictures of the orange peel before removing the coat, but this is with two coats of clear.
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@CudaChick1968 @harrisonm
 
Thanks! They only mention aluminum in the product description, but that will work on any polished metal?
 
Everybody is a beginner at some time. About 20 years ago, I bought a $99 Eastwood powder coating gun, and the rest is history. I have never used the Cerakote, but I know a professional powder coater who uses it all the time. Let me suggest one thing. It is rather labor intensive and will take a while, but it is something you can do with basic equipment. Did you know you can polish cured powder like paint? Try this. Put two coats of clear on one of those parts, wet sand it with 1500 grit sandpaper followed by 2000 grit, and then polish the parts by hand with a microfiber towel. Will it be a pain? Yes. Will it work and give you a like glass shine? Yes. I have done it a few times, and it does work.
On your second coat, you can try one of two things (FIRST, make sure you have a GOOD ground):
1. Using your laser thermometer (I assume you have one) let the part with the first coat cool down to about 160 degrees and then spray on the second coat. Powder will stick better on a warm part.
2. Try hot flocking the second coat. Hot flocking is spraying the powder on to a part right out of the oven when it is 375 degrees (or whatever you use). The powder hits the part, instantly sticks and instantly melts and flows out. Then you put it right back into the oven to cure it. It works very well, but you have to be careful. It is really easy to get the powder too thick; thick enough to actually run and drip. However, if you are careful, it can work for you.
 
clear powder coating is an odd duck. Two of the companies I work for do a lot of powder coating with color, clear, wrinkle quite a variety of finishes. If you are spraying clear on brass without a base color the results you are getting are par for the course. You can put it on fat and smooth it out after curing but it's a lot of work for pens. The powder coat lines at these places are set up by the pros at Nordson, 3M etc. The rate of line speed is set, the amount of powder and even the guns or turbo discs (wet paint) have a preset velocity and pattern of movement. The parts all run through a sophisticated prewash system and curing oven with predetermined line speeds and temps. The one you did in the picture looks good. Put one in a "lathe" and make it spin at a slow set rate and apply your powder in a uniform fashion but phat and cure. Experiment with your curing temperature and you might find the correct formulas for slicking out that clear. Also...are you preheating the brass before applying the powder? Some of the best results come from the heat from the dry off oven after parts are washed yet before the powder is applied. Cool project! It's nice you get to try and help your pop on this. Good Luck!
 
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What Is Clear Powder Coating? These guys are using only acrylic powder for clear coating. When enhancing base coat color they are applying the clear to the color during the curing process. This idea can be applied to your second coat of clear as you have no base color. If preheating the brass a bit before applying your clear doesn't fix your orange peel I would try the second coat during curing process and let the powder "melt" into the original coat. "Harrisonm" found this out through his own experimentation and is leading you down the right path if you don't want to do the post painting smoothing and polishing. One of the companies makes lockers for pro football teams and the military. I can remember several years ago making lockers for the Jets and the line never stopped between the first and second coats and the parts were not removed and rehung. The powder was melted into the green and silver parts and the finish was top shelf, several mils thick and shiny.
 
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Thanks everyone. I've been interested in playing with Cerakote anyway, so I think I'll reach out to them to see if there's a clear they recommend, or if I can use the MC-5100. I've read about hot flocking but had forgotten about it -- I think I'll try that with a couple and see what happens. I like the wet sanding idea, but I think I'll reserve that for plan B or C since these are relatively small parts. Definitely will file that away for future coating projects.

The powder I bought is TGIC polyester, for what it's worth.

I'll try to make time today or tomorrow to try out some of the tips you guys have offered, and I'll report back. Thanks again!
 
Clear Coat automotive finish will make it shine if that is what you are looking for. Keeps things protected from tarnishing.

Like clear coating aluminum wheels to keep them from corroding.

☆☆☆☆☆
 
I've had too many irons in the fire recently, so the pen project has been sitting. I like the clear coat automotive finish idea, but I really want to learn and practice powder coating/cerakote.

I did reach out to Cerakote asking for recommendations, and MC-156 was what they suggested. I think I'm going to get some on order and give it a try.
 
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