Super Koropon Primer.

[mustang]

This stuff was recommended to me by guys that work on seaplanes all day. I first read about Super Koropon in the RVator. Developed by Boeing for Space Shuttles, it is a two part epoxy primer that becomes impervious to all fluids except for long periods of immersion in Skydrol hydraulic fluid. I was a bit skeptical but after accidentally spilling a small amount on the floor which splashed onto my polyethylene garbage container, I became a believer in how this stuff sticks. I waited a day before wiping the mess off of the garbage can. Rather, I should have said trying to wipe it off, nothing came off even using my strongest solvents. I've never met any primer that would stick on poly before but this stuff does. Laquer thinner would not touch the cured primer, not even a trace of color on the rag!

I have been etching, alodining and then priming with this Koropon stuff and it looks like zinc chromate pretty much. Of course I have not been alodining the skins, (too big and too much splash) but the skin metal, when cleaned with solvent and prime wipe takes a solid coat which does not come off. I have been shooting the ribs and spars with my little Badger hobby spray gun with a glass jar under the spray head. This works well and I'm not losing much primer to overspray with the small gun which is sized between an airbrush and a detail gun. The Super Koropon is a bit thicker than acrylic enamel to spray so I had to open up my spray nozzle very slightly to allow a flow coat on the little parts. The detail gun handled the skins OK but so did the badger and I am just misting it on the skins to keep the weight down on the tail.


I bought two gallon cans which contain equal volumes of the primer and catalyst. Cost was about 140 Candian dollars. I'm thinking I will do the interior surfaces of the tail feathers and the interior of the fuselage. Since we have ordered the QB kit, there won't be an oportunity to do the interior of the wings, at least where the ribs meet the skins. I think this stuff will be good for the exterior too.

Cheers, Pete

[Snap]

This stuff sounds good. What sort of protection do you have to use though? Is it nasty stuff?

[mustang]

Snap,
So far, I have been wearing my normal painting mask with charcoal cartridges and a fiber pre-filter. Seems to be similar to painting with acrylic enamel, which is what I intend topcoating with. Just don't dilly dally after any spills, LOL
Cheers, Pete

[aerial]

This stuff was recommended to me by guys that work on seaplanes all day. ....

Hi Peter,

Where you the gent at Van's in August who ordered the RV-8 emp, and doing the factory tour? It sounds like you are coming right along if so.

This was the type of primer information that I am looking for. Someone with practical experience in a coastal environment. It would be nice to find someone who lives on the coast, has a built RV for at least 10yrs., primed or not, to see what kind of corrosion problem, if any they have had. My 4 is going to spend a lot of time tied down right on the coast as there are not hangers at the local airport.

David

[mustang]

David,
Yes, that was me.
Today, I was just asking about top coating exterior surfaces after riveting while priming with the Super Koropon. An aircraft painter told me today that I should use the same procedure for painting the exterior surfaces as I do with the individual parts. Scrub with etch cleaner, alodine, wash, dry and prime. I asked him about the etch cleaner getting under rivet heads and the Alodine doing the same and he said not to worry, just wash it very carefully after each step and even lightly pressure wash after alodining, let dry and prime with the Super Koropon. I was shocked, amazed, and almost unbelieving. This painter said that is the way they paint using the Super Koropon primer. \

Hmmmm, any comments about this????

Cheers, Pete

[aerial]

I don't know that I would worry about the exterior right away. I think that the alclad and plastic film will do just fine until the aircraft is ready for exterior paint. I am not so worried about the outside which is visible and can easily be inspected on almost every walk-around.

The fella who did my wings primed each strip of rivets. He primed every area that had the plastic coating removed, and he only removed the platstic coating on the rivet lines of the skins. I'm not sure if you can alodine partial points can you? No matter how you look at it, that's a lot of work.

My inclination would be to leave the exterior until the final paint, then prep it all at once. But what do I know? Very little.

I know we all want the pefect airplane that is going to last forever, but for now we will probably have to settle for something less and enjoy it while it lasts. Where I live, when it's really really quiet, you can hear the rust.

[mustang]

Well, my intention is to paint each piece after it has been inspected. We know our color scheme so I can paint each individual piece as I build.

I do not want to leave the plastic on much longer. Evidently it gets very difficult to remove a year later. There is also the possibilty of corrosion under the plastic in moist environments. I figure if I prep and paint the pieces, I won't have to worry about them until assembly when I can mask and paint the trim with the aircraft as a unit later. Another factor is that it is a lot easier to paint the pieces than it is to paint the whole thing at once.

I'm waiting on an inspector right now before I button up the last skins on the HS and VStab. The Canadian way EH?
Cheers, Pete

[aerial]

Are you able to get a "repairmen's certificate" for your RV in the Great White North? I remember when I went by the little airstrip outside of Vancouver, a couple of pilots there told me they flew to the US all the time. I never thought to ask if there was any advantage to registering their aircraft in the US and just parking it on the other side. I bought my motorcycle in Canada because it was cheaper. I liked the NAFTA free trade agreement.

[Thermos]

Hey Pete, where'd you get the Super K at that price? I paid about $20 USD more for the same 2-gallon kit!

Cheers,

Dave

[mustang]

Dave,

I got it from Lindair at CYVR southside. I think they sold it to me cheaper because it only had 9 months of shelf life remaining. Max shelf life is 12 months.

Cheers, Pete

[mustang]

Aerial,
When you own a homebuilt in Canada, you can do anything you want on it. I bought a homebuilt Pitts years ago and we fixed anything and everything on that little porker.
Cheers, Pete

[rigster]

Any of you super Koropon primer users have a source in the US.

Thanks

Dave

[Thermos]

Sorry for not seeing your post earlier Dave, I bought my Super Koropon directly from PRC-DeSoto. Call them at 1 800 237 6649.

Hope this helps...

Dave

[rigster]

Dave,

Thank you for the reply, I will call them tomorrow. Is there a part number or will they know which one everyone is using?

Thanks

Dave

[Thermos]

Dave,

There are three different kinds of Super K, they're all pretty much identical except for color if I recall correctly. I use 513K009 for no other reason than it's a nice, bright yellow.

I don't know how to post stuff in the Document Share; if you'll shoot me a PM with your email address, I'll send you the spec sheet/application guide.

Dave

[spikescopilot]

I don't know how to post stuff in the Document Share; if you'll shoot me a PM with your email address, I'll send you the spec sheet/application guide.

Dave

Shoot Spike an email and he'll get it up there for you.