Is there any direct to metal paint system in use in GA?

MedEwok wrote:

Euch ist richtig weil du mehrere Leute ansprichst und sich Flieger alle duzen

Liebe Grüße nach Niederösterreich!

Dankeschoen!

Steve6443 wrote:

with a Mac at least

Thanks for the tip!
I’m swimming in Linux… and am too lazy to set up shortcut keys for the Umlauted letters… maybe I should…

In Linux, go to system settings – text entry – keyboard settings – enable compose key. Chose which key you want to use (eg right alt). You can then press that key followed by a combination to get the character you want. For umlaut press right alt then tilde then u.
Simon

Thanks @simon32

Hmmm, Ubuntu has changed the System Settings menu to reflect tablet compatibility now.
They must have just changed that in the recent past.

Ironically, the keyboard option is gone. But a simple keyword search for keyboard brings up the interface.
öäü
… and we’re in business.

Thanks!

Here in the states, there are some direct-to-metal paint systems. The down side is you lose the corrosion resistant properties the primer holds.

Alodine is hardly used after production when repainting aircraft. The priming agents used have great adhesion qualities and corrosion preventative qualities by themselves and alodine is just not necessary for the hassle.

I have used many paint systems, all of which involve primer and base color coat. Clear coat (UV laquer) is dependent on the paint system. The paint system AMS3095A, which Peter mentioned seems no different than most. The primer is epoxy based which bonds to the aluminum and allows what is called a “sand free” preparation for topcoat. As long as you wait the allotted time, you can spray your top coat directly on the primer without sanding. The epoxy agents in the primer will bond with the topcoat.

Quite honestly, for GA aircraft I use automotive “grade” paint systems. The price difference between automotive and aerospace is ridiculous. Most GA aircraft don’t see the conditions these aerospace paints are designed for. Airliners are a different story, there are certain specifications that are spelled out by the aircraft manufacturer that need to be meet for the entire paint system.

Here are a few links which are very informative:

FAA Guide to Painting and Finishing Aircraft

Aircraft Painting and Finishing Manual from PTI

Peter wrote:

One problem with alodine is that it is water based and is can apparently cause corrosion if it gets into any cracks

Alodine IS corrosion (more or less, it’s highly reactive chromic acid). What alodine does is to replace the hard natural oxide layer (actually a ceramic layer) with a chromated layer, sticky and much softer. This requires scuffing of the surface to remove the oxide layer while the surface is in continuous contact with alodine, so the aliminium react with the alodine instead of the oxygen in the air. It’s a much better surface for paint to stick to than the hard natural oxide layer and it prevents corrosion if the paint should be physically damaged. When the surface is converted, all traces of alodine must be flushed off with water, or it will continue to eat up the aluminium.

Alodining an entire aircraft (instead of the individual parts and sheet metal before putting the aircraft together) sounds like a rather insane thing to do IMO. How do you get all the alodine out from all the micro cracks around rivets and joints ? That alodine could stay there for years, slowly eating up the aircraft.