Been looking at information for painting my Bearhawk airframe (the tube structure); mostly what paint to use. Several times I've read people recommending brushing instead of painting the the tubes. Does anyone really do this? The couple automotive paint shops we've talked to recommended the same. Some say brushing will use 75% less paint and we won't need to use supplied air. At first I passed the idea off as silly but maybe it is worth some thought? I done yet have a place to build a paint booth and I don't have a supplied air system. I want to airframe to look good so I've been planning to spray the paint but if brushing can provide equal coverage and appearance then it might be a good option for me.

What is "bushing?"

By bushing do you mean brushing? I don't see why that wouldn't work. When you think how much paint is actually hitting tubes when spraying I can see how you'll use less with brushing.

I need to go back to english 101 and learn how to proofread. Sorry guys. [emoji15]

I suspected as much but I honestly didn't know if you were talking about some cool electrostatic paint application process or something.

I doubt you're ever going to get a super smooth finish by brushing, maybe you don't care. I can't see it being an even application, even with strong brushing skills. Have you considered powder coating it? You truck it to the joint and their ovens are large enough to accommodate a fuselage. Chris from Shortfield had his done somewhere here in Portland and it looks really nice.

My fuselage needs lots of touch up. I've wondered the same thing about where I'll be able to paint. I might have to erect a temporary booth in the backyard next summer, or truck it to Graham's shop at McMinnville.

whee wrote:I need to go back to english 101 and learn how to proofread. Sorry guys. [emoji15]

Haha. No worries. I was wondering if bushing is some kind of new fancy painting method!

Zzz wrote:I suspected as much but I honestly didn't know if you were talking about some cool electrostatic paint application process or something.

I doubt you're ever going to get a super smooth finish by brushing, maybe you don't care. I can't see it being an even application, even with strong brushing skills. Have you considered powder coating it? You truck it to the joint and their ovens are large enough to accommodate a fuselage. Chris from Shortfield had his done somewhere here in Portland and it looks really nice.

My fuselage needs lots of touch up. I've wondered the same thing about where I'll be able to paint. I might have to erect a temporary booth in the backyard next summer, or truck it to Graham's shop at McMinnville.

I agree that brushing will likely not leave you with a smooth looking or even surface. But maybe that's not important? It also seems like it would be easy to miss spots with all the crazy angles??

The only negative I've ever heard about powder coating is that it could hide small cracks.

Can you get a good aircraft/automotive paint in a rattle can for spraying the frame? You may have less overspray doing that than with a spray gun. And, in my minimal experience (not on airplanes), it can look just as good when prepped and applied properly.

Zane, I vote yes on setting up a temporary booth and doing it yourself. Just watch the wind and wait until your neighbors are gone to paint.

CW

Whee,

get yourself one of theses 2qt pressure pots.

http://www.northerntool.com/shop/tools/ ... _200520369

The pot system is a great value at less then 1/10 of a AMU!

Throw the gun in the trash or sell it to some one you need to get even with. It might be good but it looks like trash?

Get yourself a small gravity feed HVLP touchup gun, down size the paint feed hose, and hook it up to the pot accordingly.

This way you can get around all the tight places and corners of your frame. Be careful though, you can spray paint in your eyes with this rig quicker then you can say, damn that burns!

I have seen powder coat flake off with rust underneath. I have seen powder-coat with millions of tiny little rust spots. The shop up here in Anchorage supposedly has it figured out but... They did my Tripacer gear after Krakey worked his magic on it but it sits on the wall of the hanger for more then half of the year so hard telling. It sure looks pretty.

I like any of the BMS10-11 products Axion and Desoto make them. Epoxy polymid primer. Top coat with any polyurethane for unbeatable protection.

You will love this little pressure pot until you have to run a gallon of solvent through it to clean her.

Some day I will write up my Ziplock bag no/clean pot liner for my gravity gun...


Rocket

I usually brush the joints first...hardly takes any time to put on a couple coats and work them into those angled weld joints. Then spray with a gun with a tight pattern. LP guns are much better for an enclosed space...it gets on less stuff and wastes less of that (very) expensive paint.

Originally I was planning to have the frame powder coated but after talking to a bunch of people and reading here I decided against it. People talk about the coating hiding rust and cracking when the tubing flexes. I believe it because I've seen it happen on my snowmobile.

Even if I spray it the finish isn't going to be super smooth but I don't want it to have brush lines either. I want it to look good not just "good enough."

Whee

I was just going to repeat my earlier posts that powder coating can hided rust and cracks.

I learned this from the top local powder coating shop in my area at the time.
He actually had motorcycle frame parts where he could bend the broken tube and most of powder coat was still holding it together. Was ok of my old 77 Int. Scout stuff, but NOT when it came to my 170 motor motor mount.

Also it seems the default color for motor mounts is black - (no-see um leaks b lack) Mine was painted WHITE.

2c of a Wannabe that's been there done that.

+1 on the BMS10-11, amazing stuff, not even technically required to be top coated, but a good idea anyways.

Also plus one on the no powder coat, it easily hides corrosion until it's progressed to the danger point. If there's any chance you'll be operating around moisture I'd avoid powder coat.

Spraying is fun! If you take the time to spray I think you'll be happier with the results than brushing

Hi Jon,

For me, the only bits of tube I regularly see are the V bars and the skylight stuff. I used a two-pot system for those places. If I had brushed paint on elsewhere, it would have been of no consequence, nobody ever sees it. If you use a small roller, you could avoid uneven brush lines. Thin the paint a little more than usual and the brush lines or roller dimples should blend out, unless it's a very hot day.

The best paint I have ever seen, is the stuff Bearhawk Aircraft uses. Maybe call up Mark Goldberg and ask?

I was told it's military grade stuff the Navy use on the American battleships, and I believe it too. It is VERY hard to remove with any power tool I tried. I can't recall what it's called, but it's virtually bullet proof.

As you already said, spray painting will have massive wastage, but you will get that super-smooth look. I scratched the paint a bunch by accident while finishing building, so I ended up doing a lot of touch-ups anyway.

For the record, my fuselage is painted and I'm painting everything else, BUT... powder coating is great for aluminum, maybe not so much steel. It suffers when it's damaged or if applied to a less than clean surface. Any water leaks in and it's pretty rough from there on out.

There are transparent powders that you can see the metal clearly through that look really cool. I've used it on aluminum and it creates a neat anodized look.

John Roberts of AVWELD showed me a trick little roller a couple years ago, it was made just for tube painting. As I recall it had 2 soft foam rollers, that were angled in such a way as to lay down a coat of paint evenly on about 180 degrees of the tube. By it's design, it would work on a wide variety of tube size. He raved about it, that tool along with hitting the joints with a small spray gun is the way I'll go again if I need to.

No matter how you do it, painting the an air frame is one of the most onerous jobs there is on a build, and I've done 5. You will be amazed how many times you think you are done, but then find a section missed! PITA, but I also wouldn't go the powder coat route. UNLESS, it was done by an airplane guy who could convince me it was prepped properly, even then It's tempting, saving all that labor and aggravation, but also costs more dough then old school paint, besides the other issues. Other then labor saving, I don't see any advantage to it.

I did my original panel, before replacing it with CF, with powder coat. I roughed it up with 80 grit, and had kind of a textured trunk liner spatter coat type of coating done. It was bullet proof, agreed, great on aluminum.

Am I wrong on what a PITA it was Zane?

courierguy wrote:J
Am I wrong on what a PITA it was Zane?

Probably not, but I wouldn't know. Mine came painted from the factory

Still, I plan to shoot my touch ups with my HVLP. That will be a pain in the ass with all the masking.

whee wrote:Originally I was planning to have the frame powder coated but after talking to a bunch of people and reading here I decided against it. People talk about the coating hiding rust and cracking when the tuning flexes. I believe it because I've seen it happen on my snowmobile.

Even if I spray it the finish isn't going to be super smooth but I don't want it to have brush lines either. I want it to look good not just "good enough."

I was going to say I've seen powder coating a few times, I didn't know about these problems though. Filed away for future use!

You should use an air supply regardless of brush or spray for epoxy primers. Which ever way you go, the only experience that hasn't already been shared is plenty of light so you can see. You can't get too much.

Thanks for all the tips guys. Once I decide on paint I'll do a test section with a brush and see how it goes.

Whether you're spraying or brushing or even just walking by doesn't matter one bit on what kind of air system you'll need for breathing!!! Sit down with the can of catalyst for what paint you're wanting to apply (or better yet, the tech sheets) and look for any isocyanide in any form!! Now, to explain why I'm saying this, you need to realize how they work. They're attracted to mosture...so will leap into your body and system through all the soft tissue....because we're mostly made up of water. Very simple. The MOST dangerous time is when you're mixing the paint and catalyst, because they're "seeking"! Once they enter, they don't leave until your body purges them...and that's not fun...been there, done that. It's like filling up a bucket with water...you keep putting water in and nothing happens, but when it finally gets enough and overflows, it's not just that last little bit that comes out, but a lot more! Usually with your body, that means you're really in trouble....and the best part??? It's only going to take a tiny bit to make you go through it all again!! OH BOY, what fun!!! NOT!!!
When in doubt, use a pressure air system... it doesn't have to be anything expensive. I had a student one time that built one from a cheap vacuum cleaner, a garden hose and a respirator. I think he had about $50 or less in all of it and it worked great! Spend another $50 and go get a good paint suit, and keep your Nitrile gloves on....it'll save you lots of grief in the long run. Trust me, been there, done that. It's not only you that you have to think of...but also neighbors, family, pets, etc....that stuff will travel a long ways. Simple solution...a "waterfall filter" on the outlet for the booth...it's as simple as a good mister or sprinkler that it has to flow through to get away from the booth...remember the bad stuff is attracted to moisture.

I agree with a lot of the above posts. I use a small 1 quart pressure pot, and a touch up HVLP gun. I also usually try to get 2 different colors of whatever I'm going to paint on the frame. I like polyurethane, or epoxy and go with a gray to start with and then finish with white or some bright color. Please don't paint the tubing a dark color!! They're terrible to try to inspect!!! I usually brush the "nooks and crannies" and then spray, including all the parts I just brushed. I've seen some pretty nice jobs that were just brushed as well. I've got a couple samples of some waterborn polyurethane that is awesome! Brushing gives about 90%+ transfer...you're doing well if you're over 60 or 70% transfer when spraying a tube...that's just life.
Whatever you decide to do, remember that prep is 90% of the paint job!! Clean, clean, clean and then go back and clean it again!
John