thomasyost
Member
I just finished my VS skeleton and about to attach the skin. I painted the skeleton with primer and thinking I should also primer the interior of the skin for corrosion protection.
Any ideas?
Any ideas?
Van's Air Force
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Interior Skin Primer?
- Thread starter thomasyost
- Start date
apkp777
Well Known Member
Why would you want to prime the skin? Alclad 2024 is used and to quote Alcoa "Alcladding these alloys provides high resistance to atmospheric corrosion. The clad surface is resistant to corrosive attack and also provides additional cathodic protection to the core alloy.
In order for the primer to "stick" you'll have to "scuff" the alclad, thus damaging its protective qualities and then prime it which provides little corrosive protection.
Of course, the prime or not to prime debate has been argued many times here. Lot's of thread on that. At best, I would prime the "faying" (mating) surfaces.
In order for the primer to "stick" you'll have to "scuff" the alclad, thus damaging its protective qualities and then prime it which provides little corrosive protection.
Of course, the prime or not to prime debate has been argued many times here. Lot's of thread on that. At best, I would prime the "faying" (mating) surfaces.
Thomas,
To prime or not to prime - the eternal question! This is a highly individual decision - you can find arguments from one end of the spectrum to the other if you do a search. After much consideration, I took the middle road. A major factor in my decision was, I don't live near salt water.
I am priming all the stuff Van's says should be primed, like bar stock, angle stock, anything that is not alclad. In addition, I am priming all internal structural parts, because they get pretty roughed up during the deburring process, and a lot of the alclad gets compromised. I am NOT priming the inside of skins as a cost and weight saving measure. (I own a 1969 Arrow that was not primed or corrosion treated, and it still looks great on the inside.)
I am using NAPA 7220 self etching primer. It is relatively cheap (ask them for a discount when you buy it six cans at a time), easy to use, and is available locally. Many other builders are using it. Probably not as good as a two part primer, but way easier to handle.
OK, that's my compromise solution to the priming issue. Just my humble opinion. Check back with me in 50 years and I'll tell you if I have any corrosion!
John
To prime or not to prime - the eternal question! This is a highly individual decision - you can find arguments from one end of the spectrum to the other if you do a search. After much consideration, I took the middle road. A major factor in my decision was, I don't live near salt water.
I am priming all the stuff Van's says should be primed, like bar stock, angle stock, anything that is not alclad. In addition, I am priming all internal structural parts, because they get pretty roughed up during the deburring process, and a lot of the alclad gets compromised. I am NOT priming the inside of skins as a cost and weight saving measure. (I own a 1969 Arrow that was not primed or corrosion treated, and it still looks great on the inside.)
I am using NAPA 7220 self etching primer. It is relatively cheap (ask them for a discount when you buy it six cans at a time), easy to use, and is available locally. Many other builders are using it. Probably not as good as a two part primer, but way easier to handle.
OK, that's my compromise solution to the priming issue. Just my humble opinion. Check back with me in 50 years and I'll tell you if I have any corrosion!
John
Scott Hersha
Well Known Member
I agree with Tony. Why corrosion proof something that is already corrosion proofed. I primed all the non-alclad parts internally and nothing else. I primed everything on my RV-6, but on this RV-8, I didn't and it saved my lots of time and there was less risk contaminating my lungs.
Scott
Scott
Prime or not
I did a lot of reading about primers and found that many, if not most, do NOT provide a moisture barrier. They do provide a good tooth for the paint to adhere to but do not give the corrosion protection that many believe they do. You might want to do some reading and come to your own conclusion. I agree with one of the posters who pointed out that the alclad is really all you need. B17's that sat for years had perfect interior skins with no primer or other protection other than alclad I have read reports about. FWIE
I did a lot of reading about primers and found that many, if not most, do NOT provide a moisture barrier. They do provide a good tooth for the paint to adhere to but do not give the corrosion protection that many believe they do. You might want to do some reading and come to your own conclusion. I agree with one of the posters who pointed out that the alclad is really all you need. B17's that sat for years had perfect interior skins with no primer or other protection other than alclad I have read reports about. FWIE
esjacoby77
Well Known Member
I read through all the "primer war" stuff before starting and I don't think you can go wrong either way.
Because the rattle can NAPA 7220 self-etching primer is relatively inexpensive and incredibly easy to apply, I decided to use it on mating surfaces and parts that are not alclad.
While I do think that not using primer would also be fine, the little bit that I am using is more for peace of mind than corrosion protection. As I proceed past the empennage, I can easily see myself reducing primer use even further.
Because the rattle can NAPA 7220 self-etching primer is relatively inexpensive and incredibly easy to apply, I decided to use it on mating surfaces and parts that are not alclad.
While I do think that not using primer would also be fine, the little bit that I am using is more for peace of mind than corrosion protection. As I proceed past the empennage, I can easily see myself reducing primer use even further.
thomasyost
Member
Thanks for all of your ideas.
I had two concerns when considering to prime the skins. The first was that when I debur the skin holes that I would be removing a small amount of the alclad and might provide a starting point for corrosion. Secondly, there is a reasonably good chance that I may be retiring (many more years from now) near the ocean.
I am using NAPA 7220 self etching primer and paid under $5 per can for a case of 6. I think I saw someone post a price of $9.95 on another forum.
I had two concerns when considering to prime the skins. The first was that when I debur the skin holes that I would be removing a small amount of the alclad and might provide a starting point for corrosion. Secondly, there is a reasonably good chance that I may be retiring (many more years from now) near the ocean.
I am using NAPA 7220 self etching primer and paid under $5 per can for a case of 6. I think I saw someone post a price of $9.95 on another forum.
