Primer choice and priming methods?

[con_doggiee]

So I’m starting the prime process on the horizontal stabilizer of my RV-8 and I’m almost overwhelmed at the wealth of information in this never ending debate- at the risk of igniting another debate, what’s everyone using for their primer, and what’s your general process for part preparation? Are the zinc phosphate rattle-can primers generally acceptable or are their other primers that you’d recommend along with a HVLP system application vs a rattle can? Thank you!

 

[Nashpdman]

I'm using the product linked below, I don't believe you can buy a better product. Sand the skin before dimpling, prime, then dimple. I'm priming both sides, but I'll also be the painter.

AkzoNobel 10P4-3NF/EC-117 BAC377 Yellow BMS 10-11 Type I, Class A, Grade A Spec Structural Corrosion & Chemical Resistant Epoxy Primer - 2-Gallon Kit

AkzoNobel 10P4-3NF/EC-117 BAC377 Yellow BMS 10-11 Type I, Class A, Grade A Spec Structural Corrosion & Chemical Resistant Epoxy Primer - Gallon Kit - Visit and view our entire SkyGeek, Shop Supplies, Primers, Chrome-Free Epoxy Primer, section at SkyGeek!

skygeek.com

 

[BillL]

Well, the zinc phosphate rattle cans will probably provide a good active corrosion control, but needs to be impervious to solvents or it can not be top coated. The Akzo product is active for corrosion (scratches etc) and is very tough even if not top coated.

I was going to order qt size and found the green color shipping is $23 and yellow (above) is $73. Same hazard class, same SDS. SkyGeek is puzzled and say they will get back to me on the next business day.

 

[bertschb]

I did a poll here a couple years ago and rattle cans were the #1 choice for priming. I used Akzo and would do it again. You'll get 50 other opinions so buckle up...

 

[brad walton]

You need an acid etch primer (phosphoric acid) to form a chemical bond with the aluminum. Usually followed by an epoxy primer and top coat. I like urethane top coat for its durability. There are other systems, as long as you begin with a good chemical bond.

 

[wirejock]

Whatever you choose, consider the weight vs longevity.
Weight of paint adds up
How long do you expect to own it
I sprayed P60G2 and would do it again
VANs has a sample posted here somewhere. Seems like it's going on 15 years exposed.

 

[Cessnadog]

I picked P60G2 because it was what Van’s was using on QB kits, so figured it would work fine and “match” my QB wings. it is quick and easy to spray, very light and honestly adheres was better than any rattle can primer I have found. It does require a spray gun.

I scuff with scotch brite and water with a few drops of Dawn in it, rinse with water, wipe with a degreaser and then spray. Dimple after prime.

 

[chrisskymaster]

I went with Stewart’s systems ekoprime and ekoetch. Great results with hvlp spray gun

 

[rv6builder]

M

I went with Stewart’s systems ekoprime and ekoetch. Great results with hvlp spray gun

+1. Very easy to use, Isnt going to give you cancer, seems very durable. I used it inside my -6 which lives outside on the west coast of Canada and has stood up just fine. No waste either, pour whatever you dont use back in to the can (not catalized)

Their epoxy primer is awesome too.

 

[skelrad]

M

+1. Very easy to use, Isnt going to give you cancer, seems very durable. I used it inside my -6 which lives outside on the west coast of Canada and has stood up just fine. No waste either, pour whatever you dont use back in to the can (not catalized)

Their epoxy primer is awesome too.

+1 on Stewart Ekoprime. I started using their Ekoetch, but after a lot of experimentation, decided just scuffing with scotchbrite and then cleaning with acetone worked fine for interior priming.

 

[Scott Chastain]

Good timing. The elevator hinge bracket service bulletin for my -8 involved removing so many rivets that the paint job on the horizontal stab became toast. Lucky for me, I had a spare horizontal from a later project which already had the extra bracket beef installed, so I drilled it to my airframe and am preparing it for paint as we speak. It saved me many hours of sanding and stripping and filling backcountry dings which had built up over the years.

I use Cromax VariPrime 615S Self-Etching for underside and on all the skeletal work. It saves a lot of time and weight and provides superb corrosion protection.
Then I switch to an epoxy like the Akzo-Nobel series or the Poly-Fiber EP-420 for topcoats. You will want a good epoxy primer topside for a decent paint job. If you plan on color sanding a 2-stage system and buffing for the wet-effect, I also recommend a light coat of a high-build surface primer on top of the epoxy. There is a significant weight penalty, of course, but for aesthetical appeal it provides unmatched depth and gloss. That's the route I always take. For me, the weight penalty isn't so bad with 220 horses on the nose, but YMMV.