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Minimally primed RV-12s?

ravenstar

Well Known Member
As I'm waiting for my first kit to arrive I'm agonizing over the decision of whether to prime or not, and how to do it if I choose to go that route. Since the RV-12 has been around for over a decade now, I was wondering if there are any early builders out there who chose to do the minimum priming indicated in the plans and whether they're still satisified with the results?
 
Mine is a 2010 model, I've done 2 CI's since I've owned it (I'm not the builder) and have found no corrosion...yet, but I do apply corrosion preventative compound to lower bildge area's, I'm conducting my 3rd inspection now and will re apply it...if I were a builder I would prime, maybe just because I had a 40 year career as an airline A&P and Inspector, we always were aware of potential corrosion problems.
 
Look inside the wing of a 60 year old Cessna or Piper. Mostly Alclad. It’s appropriate to prime small parts where the Alclad might have been compromised and it’s mandatory on any steel parts.

They don’t call it a “primer war” for nothing. In the end, do what makes you the most comfortable.
 
Look inside the wing of a 60 year old Cessna or Piper. Mostly Alclad. It’s appropriate to prime small parts where the Alclad might have been compromised and it’s mandatory on any steel parts.
They don’t call it a “primer war” for nothing. In the end, do what makes you the most comfortable.

I don't disagree with this but would go a step further with steel parts and also apply a top coat to fully seal the part, because many primers (other than epoxy) are porous and will not provide long term protection against corrosion.
 
I was in the same boat as you a few months ago waiting on my kit to arrive. My conclusion was priming probably isn't really needed but from all the feed back I got was if I decided to sell down the road there are a lot of people out there who wouldn't buy a plane not primed. So I'm priming the mating surfaces.
 
Look inside the wing of a 60 year old Cessna or Piper. Mostly Alclad.

Yes, but look inside the wing of a NEW Cessna or Piper and you’ll see full two-pack epoxy priming. Why? Because much of the older GA fleet are now Alclad rust buckets giving rise to a multi million dollar corrosion reclamation industry that grows annually.

When they built all those Cessnas and Pipers in the 60s and 70s they never imagined in their wildest dreams that many of them would still be flying a half a century later. They thought they’d be junked like cars. Now they know better and they’re building them to last for the long run.

The problem in the amateur-built category is that many people are fully preoccupied with saving money and time....so many just don’t prime, or they prime inadequately. They’re building aircraft to “last a lifetime”....but it’s the remaining flying lifetime of the BUILDER they’re talking about, not the flying lifetime of the AIRCRAFT. The former might be just 10 years....the latter might be 50 years.

There’s going to be an amazing number of really badly corroded RVs out there in a couple of decades.
 
9 1/2 years since first flight and no primer except as part of exterior painting process and the cockpit interior. No corrosion issues. One big qualifier: I live in AZ. It’s a dry heat.
 
Thank you all, this has been very helpful. What I'm coming around to thinking is that a quality epoxy primer is the "gold standard" for priming and will probably ensure the plane outlasts me, but there are various other degrees of protection down to no priming on alclad that also provide some benefit. The challenge seems to be much like choosing which airplane to purchase: finding the one that best suits my unique combination of environment, build ambition, and expectations. It sounds like at the very least the aircraft won't fall apart on me a year after I finish it no matter what unless I really do something terrible.

Now having said that, I think I'll probably start out at least with applying an SEM primer as I'm very pleased with how tough it seems to be and how it looks while being simple to apply with manageable (in my build environment) hazards. Steel parts will get that plus a finish coat.

I've still got a couple of months before the first kit arrives to change my mind, but at least I feel better about having a path forward.
 
Randy, at my age I’m not worried about selling mine. My guess is that when I have to stop flying I’ll donate it to a good cause.
 
I live in the humid Southeastern US and plan to make Florida (and Coastal Georgia) trips a regular part of my routine so when I start my build I will DEFINITELY be primering my plane.
 
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