Paul Dye wraps up the KITPLANES Metal Magic series with a discussion of whether or not to primer-protect aluminum structures. There’s a lot of debate on the subject, but Paul offers a few points of view to help you decide.
This series is sponsored by Aircraft Spruce & Specialty.
Fantastic video, as usual. The only thing that might be added when considering priming or not, is the corrosion protection provided if/when using alclad sheet stock. The thin layer of pure aluminum on alclad reacts with the air and forms an aluminum oxide surface possibly sufficient to convince some that primer isn’t necessary.
Great video as always. I was more than a little disappointed that you didn’t mention aluminum alloys. Many kit manufacturers, like Zenith for example, use 6061 aluminum which is quite corrosion resistant. If I remember correctly, Sonex also uses 6061 in their kits. Which is probably a major reason you SubSonex is not primed inside.
I’ve seen lots of Zenith and Monnett’s airplanes unpainted and left outside for years with little or no corrosion.
This is an excellent video with as much “un”-bias on the subject as possible. I think the presenter is well aware that we are addressing aircraft aluminum. I think one factor we can further consider is that if one chooses not to prime, there are also other preventative measures such as fogging interior structures with anti-corrosive lubricant/penetrant. I have a fogger and I find this an easy solution during the annual when all the inspection panels are off. Some, hate the run-off while others see it as a sign of protection. Again, you choose…
As usual, an excellent episode. Thank you for doing the series! I do want to comment on something I noticed while watching that has nothing to do with priming. However, I feel the need to mention my observation as it deals with shop safety. Your Smithy combo machine was prominent in most shots, and I couldn’t help but notice the lathe chuck key was left in the chuck. It tends to be rather nasty projectile should the lathe be accidentally turned on. Small detail, but just thought you should know…