Anyone have pictures of unprimed internal surfaces?

[Snowflake]

Originally Posted by Flying Canuck

This may be a moot point in Canada. It's my understanding that priming interior surfaces is a requirement with the MD-RA. The pre-cover inspection document lists "Are all surfaces protected against environmental deterioration" as one of the questions to be checked by the inspector.

The answer is "Yes, they're Alclad."

[Polar]

Originally Posted by Flying Canuck

Actually the more pertinent question during inspection asked is "Are all interiors treated for protection from environmental deterioration?"

Alclad must be permitted, as I've known a few local builders who didn't prime any alclad parts.

[Polar]

I suppose the answer to my original question is 'do what you're comfortable with'. I still haven't seen any proof that priming is necessary, but I'll probably prime the inside of my wings too, darnit. I actually don't mind priming. I worked in a bodyshop as a kid, and I don't mind the smell of solvents at all. But the prep work! Ugh, the worst.

Thanks for all the thoughtful replies.

[wirejock]

Originally Posted by Polar

I suppose the answer to my original question is 'do what you're comfortable with'. I still haven't seen any proof that priming is necessary, but I'll probably prime the inside of my wings too, darnit. I actually don't mind priming. I worked in a bodyshop as a kid, and I don't mind the smell of solvents at all. But the prep work! Ugh, the worst.

Thanks for all the thoughtful replies.

Cody
Use a really good respirator. You shouldn't smell anything.
I used P60G2. Very light and dries quick.
Prep is not bad. Some disagree but I did a light scuff with scotchbrite on a random orbital. Prior to spray, scrub with grey scotchbrite and Bon Ami. Rinse well. Dry and spray within an hour. If you plan to spray an interior color, spray within 30 minutes for max chemical adhesion.
I have two tests.
1. Test sample to my Sweetie to see if she can scrape anything with her razor sharp nails. No failure yet.
2. Rub a big piece of Gorilla tape on the part.Leave overnight. Rip it off. No failure yet.

[sblack]

Originally Posted by Flying Canuck

This may be a moot point in Canada. It's my understanding that priming interior surfaces is a requirement with the MD-RA. The pre-cover inspection document lists "Are all surfaces protected against environmental deterioration" as one of the questions to be checked by the inspector.

That is interesting. Alclad is a protection against corrosion. So it comes down to how that requirement is interpreted. I suppose steel parts are not alclad, nor are 6061 parts, so they need some sort of protection. But it could be argued that 2024T3 is protected. That is why the alclad is there. It all comes down to what your inspector thinks, or what the MD-RA policy is. You should call headquarters and ask. It is hard to imagine that they can demand a higher standard than a certified airplane, but then you never know.

[Vlad]

I will get you some pictures from inside in couple three weeks Cody. I will be doing my quarterly condition inspection in a Canadian hangar and will access tight spots. I didn't prime/paint any surfaces and I do a fair amount of coastal flying. You will see what salt environment does to alclad. Prime if you plan to fly intensely. Choose a high quality primer vs cheap rattle can. I am not a chemical expert but I've seen peeling primer on an airframe still under construction.

[Snowflake]

Originally Posted by sblack

It all comes down to what your inspector thinks, or what the MD-RA policy is.

No. MD-RA is not a regulatory body, and is not allowed to require things that are not in the regulations.

[f1rocket]

From your signature, I see you're in central Alberta. No salt water oceans in Alberta that I'm aware of. Lots of fresh water lakes though.

Is your RV going to be on floats?

Will it be tied down outside all the time?

Then maybe, some corrosion protection might not hurt. Otherwise, it's a huge waste of time and money, but mostly TIME. You'll be amazed at the time it will add to your project over several years. If you experience "non-primer remorse" after your RV is built, you can always fog the interior surfaces with a corrosion inhibitor. I believe Cessna, Piper, and Boing have something.

As for a picture, here's the tailcone of my RV-12.



It will probably look that good 20 years from now, long after I'm dead.