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RNB

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I would like to play around with some painting, specifically for now some priming. I have ordered some rattle can primer and now want to order some 2 part epoxy primer to mix up and spray on, I think with a gun from Harbor Freight.

I'm looking at Spruce and the choices seem too plentiful. I'm going to read more here on this forum, but want to ask, is there an easy way to decide?

For now my plan is to paint the light kit one method and the control surface kit another, then likely go with one or the other for the bulk of the plane. I'm not worried about color, though I will likely try for gray or white over a green or yellow as I do not plan to finish my interior.
 
Choose one system and stick with it throughout your build. You keep the same gun setting at every paint session, no need to remember the different paint mixture ratios, different viscosity, etc. Paint is paint. If you decide on 2 part epoxy primer, then stick with it and prime everything with it. If you want to paint with the latest polyurathane automotive paint, or the old aircraft formulation, then stick with it. They all worked before. Think of production line. If you keep on switching paint/primer system, you never finish.
 
The Harbor Fright HPLV purple guns work just fine, just clean immediately after use. If you walk away for a few minutes, wipe the nozzle area with MEK. Put a pressure regulator at handle but cover plastic viewing plastic. I was using an acid etch primer for skins, and 2-part epoxy for ribs, frames, etc. Hated the etch primer coverage look so now just one product. I also alodine, so my 2-part epoxy is specific for alodine coverage. These paints and thinners have killer VOC's so strongly suggest a full face respirator with external airflow. I have also used rattle can primer for small items.
 
RNB said:
I would like to play around with some painting, specifically for now some priming. I have ordered some rattle can primer and now want to order some 2 part epoxy primer to mix up and spray on, I think with a gun from Harbor Freight.

I'm looking at Spruce and the choices seem too plentiful. I'm going to read more here on this forum, but want to ask, is there an easy way to decide?

For now my plan is to paint the light kit one method and the control surface kit another, then likely go with one or the other for the bulk of the plane. I'm not worried about color, though I will likely try for gray or white over a green or yellow as I do not plan to finish my interior.
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Don't be overwhelmed. We have been immobilized due to it. NOTHING has been as bad as somone on this forum believe.

Best of luck!
Mike
 
Just another option. As someone else said, 2K epoxy primer is 2K epoxy primer.
Check out Kirker EnduroPrime. Fairly inexpensive. Available in white, gray and black. I have sprayed all three. My interior is gray and black. It's 2.1 VOC. Use a good respirator. I brush it on fiberglass as a high build primer to fill pin holes and cut it 10% with slow reducer for spraying. Auto Body Toolmart sometimes has a free shipping promo.
 
One thing that might help is to evaluate and understand your goals here. Priming can be thought of as “grades” of protection.
Bare Alclad inherently has some corrosion protection as it is manufactured.
Self etching wash primers, like P60G, which has been used on QB kits forever, provides a first level of protection. Although the manufacturer recommends top coating, there are thousands of RV’s flying with no other protection on interior parts. Scott McD did a basic test at the factory whereby he hung bare Alclad strips and P60G strips under the stairs outside at the factory. After some time, the bare parts had corroded but the self etching wash primers parts looked great. Keep in mind, one factor that led to Vans debacle was QB kits shipped from overseas with improper priming. They corroded in transit. This was a first and all the previous QB’s with proper wash primers made it just fine.
Acid Etching and Alodine conversion has been a staple forever in aircraft manufacturing. It requires a primer coat, which may require a top coat.
After etching and conversion, the most complete protection are your two part epoxies and a top coat.
On my aircraft, all interior unseen skins and parts are P60G. Inside cockpit and visible parts were primed with P60G and top coated with PPG Concept, a basic auto industry product. The exterior was acid etched and alodine with a single part primer and top coat.
Keep in mind, each level of protection adds cost, labor, and some weight. The level of protection you need may be influenced by the environment you intend to store the aircraft in.
There is no wrong or right answer which leads to the never ending debate…..
 
JonJay said:
One thing that might help is to evaluate and understand your goals here. Priming can be thought of as “grades” of protection.
Bare Alclad inherently has some corrosion protection as it is manufactured.
Self etching wash primers, like P60G, which has been used on QB kits forever, provides a first level of protection. Although the manufacturer recommends top coating, there are thousands of RV’s flying with no other protection on interior parts. Scott McD did a basic test at the factory whereby he hung bare Alclad strips and P60G strips under the stairs outside at the factory. After some time, the bare parts had corroded but the self etching wash primers parts looked great. Keep in mind, one factor that led to Vans debacle was QB kits shipped from overseas with improper priming. They corroded in transit. This was a first and all the previous QB’s with proper wash primers made it just fine.
Acid Etching and Alodine conversion has been a staple forever in aircraft manufacturing. It requires a primer coat, which may require a top coat.
After etching and conversion, the most complete protection are your two part epoxies and a top coat.
On my aircraft, all interior unseen skins and parts are P60G. Inside cockpit and visible parts were primed with P60G and top coated with PPG Concept, a basic auto industry product. The exterior was acid etched and alodine with a single part primer and top coat.
Keep in mind, each level of protection adds cost, labor, and some weight. The level of protection you need may be influenced by the environment you intend to store the aircraft in.
There is no wrong or right answer which leads to the never ending debate…..
Click to expand...

I might not do anything to the plane I build. It is not needed and my 1974 C172M was not primed and had no issues.

My goal in doing this with the practice kits now is to determine what works for me and what my tolerance level for doing so is. If the process worked out ok I would consider painting the plane myself. My 172 was 20K plus to paint.

The bit I think I have picked up is that a two part epoxy primer is likely the most durable. But when I search on Spruce for "epoxy primer" 71 products get returned. That is the part that was frustrating. I don't want to deal with hazard disposal.

I like the Kirker EnduroPrime idea ($$$)
 
Well here's another angle on it.. the alclad parts (most of the airplane) do not need to be primed. The idea behind alclad aluminum was to eliminate the need for priming and paint. Especially true for the interior surfaces that are never exposed to the outdoors. Scuffing up alclad aluminum kind of defeats the purpose. Just adds unnecessary complexity and cost.
 
71459 said:
Well here's another angle on it.. the alclad parts (most of the airplane) do not need to be primed. The idea behind alclad aluminum was to eliminate the need for priming and paint. Especially true for the interior surfaces that are never exposed to the outdoors. Scuffing up alclad aluminum kind of defeats the purpose. Just adds unnecessary complexity and cost.
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Yes, to help 2024 alloys be better at corrosion resistance, but 2024 is still considered to have poor corrosion qualities. Alclad certainly helps, but it didn’t help all those QB fuselages Vans lost to corrosion in transport.
Also, none of your extrusions are Alclad. They are bare 2024.
That said, your airplane will likely outlast you and maybe the next guy….
 
Where I primed (initially the entire tailcone and emp, but thereafter just the faying surfaces and anything that wasn’t ALCLAD) I used Stewart Systems water based primer with good results. However, I basically got tired of all the metal prep work and decided that unscratched ALCLAD, as has already been mentioned, was good enough. I live in a saltwater environment and my unprimed interior wing skins look good as new. YMMV……….
 
Couple more points. Probably covered in the Primer Wars thread.
-Easiest is self etch. Several really good products. SEM & NAPA 7220
-I also sprayed everything with SW P60G2. Easy to use. Weighs almost nothing. Still a bit of extra work.
-That leads to the last point. Watch the weight in the empennage. A nice coat of epoxy primer with a top coat inside then another primer and top coat outside really adds weight where you probably don't want it.
If you don't live near a caustic environment, consider leaving it bare and only rattle can priming where Vans suggests.
 
RNB said:
I would like to play around with some painting, specifically for now some priming. I have ordered some rattle can primer and now want to order some 2 part epoxy primer to mix up and spray on, I think with a gun from Harbor Freight.

I'm looking at Spruce and the choices seem too plentiful. I'm going to read more here on this forum, but want to ask, is there an easy way to decide?

For now my plan is to paint the light kit one method and the control surface kit another, then likely go with one or the other for the bulk of the plane. I'm not worried about color, though I will likely try for gray or white over a green or yellow as I do not plan to finish my interior.
Click to expand...
Brian has the Paint Society YouTube channel and I have learned a lot about painting process, good reasonable price equipment, and supplies. I may not learn something every one of his videos but I have learned a lot to make paint touch up on my RV aircraft much easier.
 
RNB said:
I'm looking at Spruce and the choices seem too plentiful. I'm going to read more here on this forum, but want to ask, is there an easy way to decide?
Click to expand...
No. But you are 25-50 miles from salt water. That may point you towards a more robust priming system than someone who lives in a less humid/salty environment.
 
Back when I built (2014-2017) the wife refused to have any toxic chemicals around the kids so I went with Stewart systems EkoPrime

stewartsystems.aero

EkoPrime

EkoPrime EkoPrime is a single-part, water-based primer designed for use on metal, composite, fabric, wood, vinyl, and many plastics. EkoPrime is primarily designed to provide very effective corrosion resistance for steel and aluminum surfaces and to create an excellent surface for EkoPoly...
stewartsystems.aero stewartsystems.aero

(water-based) and used a decent quality airbrush to apply it. Took maybe 3 times as long to apply as a spray gun but not a big deal and it was easier to get in the corners and small parts and no cleanup; just toss the airbrush into a cup of water and take it back out for the next session.
Obviously not as industrial-strength as epoxy but after 8 years looks good as new. My Cessna 152 with no primer was 50 years old and and looked fine too.
 
Oh, and keep notes on batches. (if 2-Part primer) i.e. small batch X of Solids X of Hardener and X of reducer (thinner), for medium batch and for a large batch.

Get a Zahn Cup for the primer you'll use.
Old timer seeing my setup said "Thin to Win!" so if the Zahn time is 18-25 seconds, thin for 18 seconds.
 
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