Paul Thomas
Well Known Member
**This is NOT meant to start a primer war. However I do want to hear everyone's opinion and hope we can disagree cordially **
If you don't want to read the whole post, my questions are at the end.
I'd like to start by saying that I'm a firm believer in being an independent thinker and coming to your own decisions after you've done your research. However that doesn't mean you can't ask people for their opinion, it's actually a form of research.
I asked some builders at the airport for some priming suggestions. The idea I liked best was to use a Zinc Chromate Wash so I researched it further and found the following:
Needless to say I'm a lot less enthusiastic about using it since I live in Florida. The airport I will be based at is in proximity of the ocean, and I plan on using a tie-down so corrosion protection has my attention.
I like the idea of using the wash because it's easy to apply. Would using a topcoat of epoxy such as AKZO on it solve the depletion issue? Of course the article doesn't state how long that would take so we could be talking decades.
The reason I'm looking at the AKZO is that from what I've read it seems to be the toughest thing around, simple to use and white which makes it look nice. The cons are that it takes time, space, and has got to weight a ton to prime everything correctly. I'm still unsure as how I would use it, just some area or everything.
My first train of though was to only prime what Van's tell you to prime because the alcald will protect the rest. This is simple and keeps the airplane light which I really like so I haven't completely disregarded that option. However, I want to do the "right" thing and I'm asking others for their opinions so that I can a better decision.
What did you use, why and what is your local climate? (If you didn't build, how much did you factor in primer and the location of the plane.)
What are your thoughts on a Zinc Chromate wash + AKZO and how would you use the AKZO?
What are your thoughts on just prime what Van's tell you to?
What would you use in a humid climate next to the ocean if you were parked outside?
Thanks all for reading this long post and sharing your opinion. I'm sure this will help me make a better decision and will have me armed and ready when I call the manufacturers for more information.
Paul (Not sleeping while waiting for an RV-7 emp kit and trying to make up my mind )
If you don't want to read the whole post, my questions are at the end.
I'd like to start by saying that I'm a firm believer in being an independent thinker and coming to your own decisions after you've done your research. However that doesn't mean you can't ask people for their opinion, it's actually a form of research.
I asked some builders at the airport for some priming suggestions. The idea I liked best was to use a Zinc Chromate Wash so I researched it further and found the following:
http://www.paintcenter.org/rj/jul02k.cfmZinc chromate is simply a corrosion resistant pigment that is added to certain coatings. In the case of a wash primer, the phosphoric acid actually reacts with the metal, whereas in the case of zinc chromate this is not the case. In dry, low humidity weather the zinc chromate does not do anything other than remain in the coating. On the other hand, when the humidity in the air increases, or on a rainy day moisture for the air penetrates the primer coating and slightly dissolves the zinc chromate. The dissolved zinc chromate solution now does react with the underlying metal surface and forms a passive layer (like a blanket|) that prevents corrosion. As soon as the weather becomes dry again the zinc chromate no longer pays a role ... at least until the next time it rains, when the process is repeated. If there are frequent cycles of high and low humidly the zinc chromate will eventually be depleted and soon after you might start to see corrosion of the metal..
Needless to say I'm a lot less enthusiastic about using it since I live in Florida. The airport I will be based at is in proximity of the ocean, and I plan on using a tie-down so corrosion protection has my attention.
I like the idea of using the wash because it's easy to apply. Would using a topcoat of epoxy such as AKZO on it solve the depletion issue? Of course the article doesn't state how long that would take so we could be talking decades.
The reason I'm looking at the AKZO is that from what I've read it seems to be the toughest thing around, simple to use and white which makes it look nice. The cons are that it takes time, space, and has got to weight a ton to prime everything correctly. I'm still unsure as how I would use it, just some area or everything.
My first train of though was to only prime what Van's tell you to prime because the alcald will protect the rest. This is simple and keeps the airplane light which I really like so I haven't completely disregarded that option. However, I want to do the "right" thing and I'm asking others for their opinions so that I can a better decision.
What did you use, why and what is your local climate? (If you didn't build, how much did you factor in primer and the location of the plane.)
What are your thoughts on a Zinc Chromate wash + AKZO and how would you use the AKZO?
What are your thoughts on just prime what Van's tell you to?
What would you use in a humid climate next to the ocean if you were parked outside?
Thanks all for reading this long post and sharing your opinion. I'm sure this will help me make a better decision and will have me armed and ready when I call the manufacturers for more information.
Paul (Not sleeping while waiting for an RV-7 emp kit and trying to make up my mind )
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