Alodyne spar countersinks instead of priming?

[Captain Sacto]

Question for those with an interest in corrosion control.

I just finished installing platenuts and countersinking the main wing spar flanges (and inboard web). Van's directions calls for spot priming the countersinks, and while it's no biggie, I would rather use an alodyne pen on the exposed aluminum in the countersink ring.

Then, I'll prime the wing skin that mates with the countersink (e.g. the wing tank skin-to-spar attachments.)

I can't imagine any "issues" doing this, but I thought I'd run it by the VAF forum before blithely messing up a spar flange. Comments (and critiques) kindly invited.

Thanks in advance.

Tom in Sacramento.

[terrye]

The main wing spar is anodized, not alodined, so you're not duplicating the anti-corrosion process that was originally applied if that's what you are thinking. I would be concerned about being able to completely wash the alodine off of the bare aluminum when you're done, especially if any gets between the nutplate and the spar flange or around the AN426 rivet holes. I primered mine with epoxy and applied it with a Q-tip.

[Captain Sacto]

Terrye, thanks for the info (and I'm glad I asked)

I've been using the NAPA primer for much of the interior skin surfaces, but I suspect that an epoxy primer such as you mention just might be a better product for these countersinks in structural areas.

I just looked throught the "primer" forum (whew) and also looked at AC Spruce re expoxy primers. Lots of options on primers (but I better not start anything )



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