Aircraft finishing systems (AFS)

Has anyone used the AFS waterborne one part primer??
If you have how has it held up over time ? I am wanting to start building in the next few months and am trying to figure out the BIG primer questions as soon as possible.. I will be building in the attached garage and I don't want to drive the wife and kid out of town with the fumes..
Any help would be great.
Chris
Bonney Lake, WA

3 years of sitting in the hangar (not flying yet) -- no visible degradation. Holding up well to the abuse of assembly and repeated handling (ie empennage). Andy Karmy has probably been flying with it the longest, you might contact him if he doesn't see this thread.

Toughness is proportional to the thickness of the coat. Thin coat = can scratch off with fingernail. Thick coat == fairly resilient, not "hard" like an enamel, but will still protect against abuse. A medium buildup (metal slightly visible) seems tough enough for most purposes.

It still makes fumes, though less than the alternatives. I cannot recommend spraying it in an attached garage w/o ventilation.

I used it early on, then switched to a self-etching auto primer I could obtain locally. It's been a few years ago but I recall that it was slow to dry...like overnight slow. It seemed to require multiple thin coats. Orange peel was common but all that might have been my technique or lack thereof. It requires etching (but not alodining), so there is an additional step beyond a self etching primer. It smelled about as strongly as other paints, I thought. It dries hard but seems thicker than the primer I'm using now. It is advertised as a seal coat as well as a primer, as I recall, so it may provide more protection from corrosion than auto primer, but I'm just guessing. I might try it again in the future. BTW, I sealed up the seams on the forced air furnace in my shop with a roll of aluminum tape and that cut down the smell in the house a bunch. Almost undetecable now.

Chris,

I have the same report as Paul. I used AFS on the empennage and wings, but it's just been in storage since. The paint has more of an ammonia smell than the spray can stuff I've been using lately (SW GBP-988).

Andy flies out of Auburn, so you can probably even check out his plane if you ask him. Or I think he shows up to the Puyallup EAA meetings still. That's a good RV chapter, by the way.

Dave

I used it per Andy Karmy's website and would use it again. I sprayed two light coats, dried enough for riveting in a couple hours, cleanup with water, and very tough. Also used AFS topcoat paint for my interior. Wish I had used it on the exterior.

AFS Primer

I've been using it in my garage for over a year and have been quite satisfied. Ive been using the cheap spray gun Vans sells - good enough for priming internal structural stuff (I'm not priming most alclad parts). Be sure to use the etch prior to priming - the fumes from that are much worse than the paint. It does take multiple coats (as specified in the directions). I found it dries to the touch pretty quick, but requires overnight for full cure (I've found much the same using the Sherwin Williams self-etching primer as well). When dry it is very tough - I often primed before dimpling and the primer survives dimpling just fine. I use the SW primer for quick small stuff (not worth the hassle of using & cleaning the spray gun).

I also used some of their finish paint for the first time last weekend - painting the inside of my tipup frame prior to installing the stiffening kit. I have a Lowes HVLP spray gun for that. I was pleasantly surprised with the results. I didn't set up a spray booth, but used a fan nearby to try to minimize overspray settling (for both primer and finish). The finish definitely has the 'wet look' when dry, and it takes a while to dry - 2 hrs before dry to the touch (I don't know how long auto paints take). The smell of the finish paint is stronger than the primer.

I just bought some

I just purchased a gallon of their primer and will use it on my wing kit.

I used Marhyde Self Etching primer on the emp mostly from the gallon can but some from the spray cans. It does not hold up well to rivets under the shop head at the dimple. Most of the time it cracks off all around the shop head here.

I hope the AFS does better in that regard.

Primer

I used Marhyde with excellent results. No cracking, splintering, etc. NAPA sells a similar product that others are having good results with also. A company called Smart Shoppers has good prices on the web for Marhyde by the case. Dimpling might be better done prior to priming.

Ron Kostus N567RK - reserved
Finish kit, etc.

I have been using AFS for three years, now. I did most of the empennage with SW 988 and enamal topcoat. I did some of the empennage, all of the wings and all of my fuselage with AFS. The AFS primer is a lot tougher than the enamal, but probably not as tough as an epoxy. It is possible to scratch it if you try, but I have never seen a scratch on parts that have been shuffled around in the garage, uh, I mean aircraft factory. After a year, yoiu can still remove the AFS with MEK, but it holds up pretty well to Lacquer Thinner.

There are a number of advantages with the the AFS primer.

• you can just pour the left over paint back into the bottle (it comes in a plastic bottle with a screw-on top).
• clean-up is with water, but if it starts to dry, lacquer thinner will take it right off, as long as it is not too dry. If it is really dry, MEK will take it off.
• it is thinned with water (I use it straight out of the bottle).
• the fumes are not as bad as most other paints. There is a strong oder of ammonia, but not nearly as bad (or good?) as the SW988.
• unlike the self-etching primers, it does not need to be topcoated in order to provide protection.

I have used the AFS Polyurethane topcoat, also, and I am very happy with the results. I painted the HS on my empennage, and I still need to perfect my technique, but the results were pretty good for a first attempt. I will be doing the whole airplane myself, using AFS.

Tracy.

I have used the AFS primer on my empennage and have been fairly well pleased. Actually, I was very pleased with how my rudder skins came out. But, then again, I guess that is what practice will do for you.

I really only see two down sides to using AFS. 1) you need to etch the parts. The AFS etch is water based, so once the etch is done and the part is rinsed, the part must be dry before priming. This obviously isn't very hard to do, but it is additional process time. 2) Cure time. If you apply a thinner coat, it will cure fairly fast, though I prefer to let it cure overnight. However, if you go heavy, it may take a long time. As in 3 days long. So, the lesson here is: 3 light coats like the AFS guys say.

The upshot is that it is pretty tough once it is cured. The only thing that has taken it off was a beating with the flush rivet set while riveting. Oops. Otherwise, it has withstood reassembly and the day-to-day shuffling around the shop with no problems. It has also stood up to the occasional stray bucking bar very well. I do cheat and tape the edges of my bucking bars for just this sort of event, so the results may have been different if I didn't use the tape.

Personally, I haven't found the odor to be particuarly foul. Keep in mind, though, that I have done all of my priming outside. I would recommend you do the same.

If you do decide to give it a try, do be sure to buy the Dupont viscosity cup and thin the primer down to 18 seconds. I have found this to be important for obtaining a nice smooth finish. Well, that and filtering like the instructions say.

All in all, it looks great once it's applied. I expect will continue to use it for the rest of the build.

Cheers,
Robert

Ditto what he said about thinning with the dupont cup. I've gone back and forth between AKZO and AFS. I really like AKZO because of how easy it is to apply. I really hate that it's trying to kill me

I've been pretty happy with AFS also once I thinned it properly. Light fog coats are called for. Nice stuff and it comes in different colors (white is my favorite now). You still need to use a mask for spraying but it's nowhere near as toxic as others.

It does take a little longer to dry. Overnight's typically good. Once it's dry, it's pretty darn tough. It'll seem dry in 20 minutes but it'll come off easily.

Thanks for all the feedback.. I do apologize, I used the search function for both Aircraft finishing system and AFS and had no matches... Today I took the time and read all primer posts and there has been all kinds of posts on this stuff...
I would say I have found my primer...
Thanks again
Chris

AFS & skins

AFS users...

I'm basically sold on the AFS primer, and have read the threads here and looked a several websites of the folks who are using it. My question here is, what about priming the inside of the skins? I was originally thinking to prime just the rivet lines on the skins, but the more pictures I look at, it appears that most AFS users are priming the entire inside of the skin.

Is it possible to prime just the rivet lines with this product? My guess is that with the etch step, it's more difficult to keep it to just the line, perhaps this is why most are doing the entire skin?

And with the etch, what about the outside of the skin--I don't intend to prime that, as I don't know what paint system will eventually end up on it. How do you keep the etch from attacking the outside of the skin (running thru the rivet holes, etc)?

Thanks...

That's easy, I didn't prime the skins. Ok, maybe not so easy, since I got rats in my wings when I stored them, so maybe I should have primed them. What a mess. BTW, I did prime the ribs with AFS, and they cleaned up pretty good where the rats had made their messes.

If you are going to prime the inside of the skins, then I wouldn't worry too much about getting the etch on the outside. The etch does not remove that much metal. When you are ready to paint the outside, you'll need to prepare the outside surfaces, again, no matter what system you use. Even if you are going to use AFS on the outside later on, you would still have to redo the outside later if you primed it now. Most topcoats need to be applied within 24 hours of priming (at least the systems that I have looked into).

So, if you are going to prime the inside of the skins, just prepare the inside, cleanup the outside, and shoot.

Now, if you are going to leave the outside unpainted, then I have no idea how gettng the etch on the outside when preparing the inside would affect this. You are on your own, there.

Tracy.

If you use the AFS etch, it is not that aggressive. Put it on, wait a minute or two and then maroon scotchbrite the area you want to prime. Wash it off. I mix my etch at 50/50 with water. This seems to provide enough etching effect but not too much. The adhesion seems to be fantastic with this combo of etch solution and prep method.

As long as you do not let it sit too long on the other areas or let it dry on an area that you do not want to prime, you will never know the difference.

I am pretty sure your question would be valid for any type of primer or etch.

The reason I prime the entire skin is because it is so easy to do. If you are going as far as to prime the contact areas/rivet lines, might as well coat the entire skin.

The AFS system was my second priming system. I stored some parts that were primed with AFS and some others that were primed with my third (and final) system. The parts were then stored in a friend's leaky hangar. After a few months the AFS primer "flaked" off parts while the Dupli-color/Rustoleum parts were unaffected. I had initially switched because I did not like that the parts would get dirty with handling. Maybe it was my clean, etch, prime technique but after the leaky hangar incident, I'm glad I switched.

Welcome to primer wars....

cwoodyfly2001 said:

Thanks for all the feedback.. I do apologize, I used the search function for both Aircraft finishing system and AFS and had no matches... Today I took the time and read all primer posts and there has been all kinds of posts on this stuff...
I would say I have found my primer...
Thanks again
Chris

Click to expand...

Chris

My intro to the Van's family of builder in AUG 2004 was by waY OF PRIMER WARS. I asked your same question and boy did I get an ear full. Folks seem to much tamer these days especially here at VAF.

I used AFS one part water borne polyuretane paint. The owner of AFS at the time gave me some great info on the difference between primer and paint. He said the AFS one part paint would do the job much better than primer without the interesting side effects that ALL primers have unless it has a coat of paint on top.........now with that said there are alot of folks out there that would argue just shot a self etch primer and be done with it. Well maybe......but Doug suggested in the long run that this isn't such a good or safe idea. (25 plus years painting planes maybe gives him a good base to give advice from). At any rate I am happy that I went with AFS.....but would probably just shot the non alclad parts with AFS on my second build. YA right 60 years old and still trying to finish my first build!!!!!!!!!!!!!

Do a search in the archives and I am sure you will come up with the best fit for you....but...please call AFS @ 1-888-356-7659 and they should give you some good info. I will say though that the new owners of AFS are a bit slower to respond to email and when I order the material take longer to get to me??????In other words customer service isn't as great as the orioginals but still OK.

Frank @ sgu RV7A "NDY"

w1curtis said:

The parts were then stored in a friend's leaky hangar. After a few months the AFS primer "flaked" off parts while the Dupli-color/Rustoleum parts were unaffected.

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Thats strange, I have had some sample parts totally exposed to the weather now for about 8 months that were primed with the AFS primer.

Look just like they did when I first set them outside except for the bird poop.

Thanks

Thanks for the skin priming information from "in the trenches," helps take a few of those 'I understand, but I'm just not sure' questions off of the newbie mind. 95% of my fabrication experience has been with wood--never needed to use etch on that!

-JDW

I sprayed some AFS primer on a test patch of Alclad and mounted it horizontally on my fence almost 4 years ago. I did the usual clean, etch, spray routine. Except for some green mold growing on it (hey, this is Seattle--everything grows mold around here), it looks unaffected by the weather.

color?

Looks like AFS might be the least destructive to my lungs to include fairly easy prep/application/cleanup. Big question, though, is what color is it? Aircraft Spruce doesn't give a color in the catalog.

madsabre said:

Looks like AFS might be the least destructive to my lungs to include fairly easy prep/application/cleanup. Big question, though, is what color is it? Aircraft Spruce doesn't give a color in the catalog.

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The primer comes in White, Dark Grey and Green. The Green is a fairly light green. I'm not cure what Spruce carries...I've always just ordered direct.

Love using AFS White Primer

I like that the AFS goes on thin and expecially the water base mixing/clean up. I just did my inside surfaces right wing top skins yesterday. The AFS cleaner with a purple scotchbrite gets the surfaces cleaner than with Dawn. THe AFS etch is also mild and effiective.

I also just got an airbrush and found I can put a light coating of AFS primer right on the rib mating surfaces for a little more protection than just alodyne (that stuff scares me and except for small parts, I may never use again) in the wing stand.

I plan to order some of the AFS paint and try our.