Another 'different version of the same $%#@!& question' thread

[MidGenerationAL]

So picking up my father's plans build four, the spars are fully assembled, alodined, and zinc chromated. The wing ribs are attached to the spars and untreated. The wing skins are untreated. All the rivet holes are drilled in both the skins and the ribs.
I'm trying to figure out what if any treatment to do on the ribs and skins before riveting them together.
"Diversity of opinions," I know.
"Great way to start an internet argument," I know.
Now that the ribs and spars are riveted together it becomes a very large part to prep and treat with any kind of wet process. Also i am concerned about exposing the finished spars to whatever I do to the unfinished ribs.
I do have good spray painting gear but I'm not aware of anything that can be sprayed directly to aluminum.
I don't live near salt water or fire breathing dragons.
This plane will become my 14 year old daughter's and I'd like it to last for her.
I'm willing to go to some hassle and expense to treat these parts if it will help but not eager to make a giant expensive mess that doesn't help anything.
Advice please.

[alaskabearhawk]

The fact you are using Alclad aluminum means there is built-in corrosion protection. From an online source:

"What Does Alclad Mean?

Alclad is a duplex metal product made by cladding an aluminum alloy core with surface layers of pure aluminum or aluminum alloy, resulting in increased resistance to corrosion.
It is a sandwich of high-strength aluminum alloy between two sheets of commercially pure metal for a combination of strength and corrosion resistance produced by rolling.
The use of Alclad results in greatly increased life for a structural part."

There are thousands and thousands of aircraft out there that are decades old with no primer on the internal aluminum surfaces and they are just fine. If for whatever reason the surface layer is scratched deep enough to compromise it, all you have to do is polish it out and use some spot primer. You'll be fine.

Your daughter should be able to pass it on years from now, that's if she doesn't wear it out first!

[gregc]

Alaskabearhawk is right, it will be fine. If some evidence would make you feel better, I can offer this (although it is only one data point). I had a C172 that Cessna built with a mix of skin panels, some zinc chromated and some not. I have no idea why. After 50 years in New England wx (mostly outdoors), the inside of the cabin area where there was a lot of moisture due to leaks, wet/snowy feet etc. had some surface corrosion on the non-primed skins. The chomated skins were perfect. So, primed is somehat better as you would expect but the difference was not great. Personally I wouldn't worry about it at all.