What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Will you please critic my process/approach please

Bavafa

Well Known Member
I really like the idea of painting before first flight and since I have not found a suitable painter, I have decided to tackle it myself. I hope I don?t end up regretting this decision.
So far, I have done much of the fiberglass work to a near paint ready stage, this is all except the cowl.
My choice of paint is a car type paint (base/clear) and I believe either Valspar or PPG would be the MFG but I like to get more info and recommendation on the MFG.
So far, the process in my head is to
- Wash clean and sand (150-180 Grid) the bare aluminum/fiberglass parts
- Take care of any of the imperfection, rivet gun smiles, with Evercoat Metal glaze and sand to feather edge
- Clean the area to be painted with acetone thoroughly
- Prime with Transtar 2K DTM primer then sand with 600 grid to get all the minor defects
- Primer- Seal with the same primer, Transtar 2K but different mixture
- Paint with base coat within the specified time (about a day) after sealer has been applied.
- Apply clear coat within the specified time after base coat

Questions:
Any other prep work on the bare metal is needed?
How important is to do the sealer if the primer is smooth and ready. Will just sanding be sufficient for adequate adhesion and bonding?
 
I would not use that aggressive of sanding on the bare aluminum. Direct to metal epoxy primer will stick fine with just clean metal and a scuff with maroon scotch brite pad. 150 grit will leave some pretty deep scratches for painting and some DTM primers are not made to be sanded like a typical 2K polyurethane fill primer. The Evercoat metal glaze is good stuff and does stick and feather nicely. Sealer before painting gives a nice uniform color base and a fresh layer for the base coat to stick to.
 
+1 on what Chris said.

I used PPG Alumiprep and Scotch Brite pads for aluminum prep, followed by a thorough rinse with a garden hose. Let dry and wipe down before prime with Coleman fuel (easier to work with than acetone.). Prime within 24 hours.

I painted two planes with PPG base and clear coat over PPG DP-40LF primer as these products are readily available at a local car paint shop, and seem to be forgiving to the amateur painter (me). I built a paint booth in the hangar using 2x4s, plastic, a big exhaust fan, some air filters and as many 8? light fixtures as I could fit in (but still wanted more light).

For all the fiberglass, after prep they got a coat of primer to make sure all was well (it never was). Sand and reprise as needed until perfect. When ready for final paint, some 400 grit wet sand then prime, base and clear like the aluminum.

Paint with the wings and tail off the plane. Mount the wings using 2x4 reinforced 4? PVC pipe across two saw horses so you can rotate them around.

This is not a one man job. Get help - preferably a real car paint guy that knows what he is doing. This will make all the difference in the world. I will soon do this on my third plane as I learn this lesson the hard way from the first two builds

Get ready for massive sticker shock when you find out how much the paint alone costs.

Carl
 
Questions:
Any other prep work on the bare metal is needed?
How important is to do the sealer if the primer is smooth and ready. Will just sanding be sufficient for adequate adhesion and bonding?

The coarsest sanded surface you should prime or paint over is 320 grit.
For aluminum, scuffing with purple scotchbrite, enough to fully remove all of the gloss is sufficient for good adhesion.

What ever paint you use, I would recommend it be purchased from a local supplier. The materials are $$$. You want to avoid running short, but you also want to avoid purchasing much more than what you need. That is difficult if you are having things shipped to you.

I strongly recommend that any novice painter first practice painting on something other than their airplane parts. Painting it your self is highly rewarding, but getting results that you are unhappy with can be demoralizing and push the cost and work involved even higher.
 
Thank you all for chiming in.
Looks like all the consensus are that 180 girt that is instructed by Transtar primer is too coarse and I will upgrade the grid.

I am planning on starting on a sample part and then smaller parts so I can gain some experience. The wheel pants and gear leg fairing would be the beginning part and then VS. Hopefully since the parts are not big (except wings and fues) hopefully they will be more manageable.

If I still can find a reliable painter, I will outsource that portion of the project.
 
Last edited:
I've seen a handful of really well-built airplanes that looked like junk because of a poor paintjob. I built my entire aircraft myself, including all the wiring, but I wrote a check for the paint because I don't know all the tips and tricks. I'm pretty sure I could learn to paint an airplane - and I'm pretty sure that the 4th airplane I paint will look pretty good - but I didn't want my airplane to be one of the first 3.
 
painting

What the other guys have said rings true. Find a reliable local supply. This is a big dollar part of the project. Prepare to be nickel and dimed (your probably already used to that). You'll burn through all sorts of misc. supplies (tack cloths, thinners, lint-free rags, sandpaper, scotch-brite, etc).

Not sure what your plan is for a paint scheme but if you are planning on a multi-color job, YOu will be amazed at how long it takes you to mask, unmask, remask, unmask, then shoot a clear coat. In most cases it all has to be done within 24 hours. Primers typically have a limit to how long they can cure before applying the color coat. You don't want to go beyond that time then have to sand it to re-apply the primer.
 
You can frustrate yourself to no end with the wrong equipment. I would recommend a cheap harbor freight HVLP gun with a 1.4mm tip for the priming. It?s very important with high build primer to use 1.4 or higher tip. For the base and clear the best gun on the market for the price IMHO is the DeVilbiss GTI Pro lite 1.3mm tip for solvents. Just be sure to run the correct pressure at the gun for base clear and a 1.3 tip with the material you recommend in your OP, plenty of YouTube vids for this. As recommended, practice on an old fender or hood from a junk yard. Also there is a detailed write up in the tips section on this forum for cutting and buffing later. Having a great paint job that you did yourself is very rewarding indeed!
 
Might consider when scuffing with scotchbrite to use water like wet sanding to contain the aluminum dust. Scotchbright is the way to go and having done it dry and also with water, water is a heap cleaner and it helps to recognize when the gloss is gone.
 
I painted my RV8 last year. I have been painting for many years, but this was my first aluminum airplane.

here is the things I recommend and why.

Use an automotive paint such as PPG concept. It is very forgiving and can be buffed. I used PPG aerospace paint and was not happy with the process. The paint is tough and may be eve a little less expensive than the PPG concept , but too much hassle. There process is designed for big shops. not small one offs.

If you have any metallic you will need to clear coat the paint. If I were to do mine again I would clear coat everything. The amount of extra weight is negligible. The BIG advantage of clear coating is you can sand and buff the clear and fix almost any sin. I would shy away from metallic if you can.

My prep was standard. I washed with soap and water. Used aluminum prep and then alodine. After that just get some expose primer and put on a good coat maybe two. If you do not use a metallic you can use regular concept for the colors and lightly sand them before clear coat. Clean prep is the key.

I would use a good gun like an IWATA. I have used harbor freight guns and they are inconsitent at best. Its expensive 300 to 400 bucks but worth every penny. You can use the Dekups system for most guns that are disposable spray cups . They make cleanup a snap and work well on the HVLP gravity guns.

One last thing. Google "the Gunman Spray painting" He is a a real character from Australia,.. You can lear a lot form his videos.

Hope this helps
 
Plus one on the gunman vids LAZ. Fun vids, but I think the brother has run too many solvents through those nostrils though. :D
 
Check out PreKote

On my latest project decided to try PreKote to prepare the aluminum for primer.
Used aldine before but not enviro friendly and just nasty. PreKote goes on with spray bottle and then scrub the area with scotch bride pad, rinse with water, air dry and prime. Easy peasy. Very happy with the result. Check out PreKote's video. Used by USAF.
 
On my latest project decided to try PreKote to prepare the aluminum for primer.
Used aldine before but not enviro friendly and just nasty. PreKote goes on with spray bottle and then scrub the area with scotch bride pad, rinse with water, air dry and prime. Easy peasy. Very happy with the result. Check out PreKote's video. Used by USAF.
Hi Mark,
Thanks for the info. How much PreKote would you say is needed for a RV? Two or three gallon?
 
Painting

Get your TDS (Technical Data Sheet) for each primer, paint etc. The TDS will tell you specific things like how many minutes in between coats. And whether to do thin coats or medium coats and whether to dilute. STICK TO THE TDS. All the professional paints will have TDS. Make them your buddy. Follow their directions.

If you have time got to Sherwin Williams class. I had a lot of fun flying to Wichita and taking the Sherwin Willliams painting class on a weekend. Of 10 students, 8 were building RVs. It was a great little vacation.
 
Back
Top