I don't know why it took so long for this to sink in; Premier Powder Coating in Rexburg sandblasts, then epoxy primes, then powder coats. I could do like robertc did and have the blast then epoxy prime but then I'd have to topcoat. This is a really good option and the price is good. Another option is to have them top the primer with a clear powder coat.

What do you guys think of epoxy priming then a clear powder coat for a top coat?

It's my understanding that powder-coating involves electrostatic application-- you charge the powder positive, and ground the fuselage, and let magnetic attraction do it's thing. Any way to use this process to apply regular paint? That would help insure paint gets into all the nooks & crannies.

hotrod180 wrote:It's my understanding that powder-coating involves electrostatic application-- you charge the powder positive, and ground the fuselage, and let magnetic attraction do it's thing. Any way to use this process to apply regular paint? That would help insure paint gets into all the nooks & crannies.

Yes. This is how Sunquest shoots their paint. I believe it's pretty much industry standard for large production paint shops. Really cuts down on the overspray.

Yep, do a little searching for electrostatic painting. It's an interesting process. I saw it done at a machinery dealership. Not a mirror gloss finish but it was acceptable for something like a frame.
John

Thought I'd bring this thread full circle.

Tried brushing, it looked like crap. Tried a roller and it didn't look any better than the brush. Used conventional spray and got the job done. Next time I'll drop it at the powder coater and tell them to call me when it's done.

Just for balance

The Cons of Powder Coating

Despite all these positives there are some downsides to powder coating. These downsides include color change difficulties, difficulties applying a thin amount of coating, start up costs, difficulty touching up missed areas, the part has to be able to be grounded, and finish appearance. With powder coating each non adhered powder particle must be collected and can make color changes difficult as the collection area for the powder that does not adhere must be emptied each time a color is changed. Thin film builds (less than 6 mils) are hard to achieve with powder coating. This is due to the powder coating process and cannot be changed ; essentially you have less fine control over the amount and speed which powder is applied to the target.. If you need a coating build of less than 6 mils, powder coating is not the right fit for your painting process. Along the same lines, due to heavier film builds and the way powder coating is done, the finish quality is usually less fine than a sprayed coating. Powder coating requires the coating to be baked which allows the coating to flow together to form the surface finish. Due to the coating flowing together you have less control over the way the material smooths out. In liquid coating work you can control your atomization level which allows for the finish to be finer as you apply increased air. Due to powder coating not allowing for small film builds, touching up a part is generally not possible as well. With powder coating you will typically need to remove all of the original coating to achieve a quality finish, with liquid coating you can sand and prepare a portion of a product and achieve a blended finish that will be hard to tell apart from the rest of the product. Powder coating is applied electrostatically and therefore your target part must be able to be painted electrostatically. Finally you have start up costs. With liquid coatings you only need a basic spray gun and a booth to be able to safely coat any product you want. Liquid coating can be applied in the open (this is not recommended but is possible) powder coating requires a booth and oven to be able to apply a coating to a part.

Looks good Whee!

Wannabe, well said...and only the tip of the iceberg in my opinion.

John

John and others:

I can not take credit for the above "cons" - picked it off of a powder coating business of pros and cons. Forgot to put in quotes and the source.

On a couple other posts I have told about the sales pitch I got when getting parts of my old IH Scout powder coated. The shop owner showed me some wrecked motorcycle frame sections. He would flex them at the break to show me that the powder coat still flexed and did not show a crack. That is what caused me to not powder coat the motor mount of my last plane.

I think the pros and cons of Powder coating vs paint have been thoroughly discussed. That discussion lead me away from PC. Now that I have painted my airframe I'm of a different option. Yes, I think paint is the better method except from the view point of a do-it-yourself amateur builder. Though we did everything we could, except hire a professional, to ensure good prep and coverage we still have spots of thin paint and areas that were difficult to reach. In our case I'd argue that PC would have provided better coverage and equal protection. As for cost: hiring a professional to paint would have been cost prohibitive for us and most of the shops we talked to wouldn't even look at it. We're about $550 in with sand blasting, primer, paint and other materials. A friend just had his airframe powder coated at a local shop, a reputable shop that has done several airframes, for $600.

But, the REAL downside to powder coating something like an airframe is when the time comes that you want to add a tab, or heaven forbid, repair an "oops". That's when powder coating becomes a real PITA, since you have to remove all the powder coat to weld the item, then figure out how to re-coat the area....which can be difficult to impossible.

Course, you'll never need to fix that frame.....

MTV

mtv wrote:But, the REAL downside to powder coating something like an airframe is when the time comes that you want to add a tab, or heaven forbid, repair an "oops". That's when powder coating becomes a real PITA, since you have to remove all the powder coat to weld the item, then figure out how to re-coat the area....which can be difficult to impossible.

Course, you'll never need to fix that frame.....

MTV

Well said. I have had the same issues on a 4X4 bumper I tried to add to.

For me, a key reason to skip powder coating the frame is the thickness and flexibility of the plastic can hide cracks and failures as they progress; I want as much advance warning as possible a crack is developing.

That said, painting seems like a nightmare I am not up to. For my build I am going with charcoal-black with a matt (non-glossy) finish, sprayed by a pro. Hopefully the imperfections will be few, and not visible.

-M3X