Quote:
Originally Posted by 911obgyn
Another product is ACF50, used on aircraft landing gear and inside of aluminum wings.
In humid climates it needs to be reapplied every 6 mo or so.
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Been using ACF50 on aircraft for 35 years. It has a few volatiles that evaporate and leaves the thin coating on the surface. I had a open cup of ACF with a brush for touch ups on drilled holes and after a year it had thickened so much it almost wouldn’t pour.
The stuff is amazing it is dielectric so it can be used on electronics with out fear of shorting. I use it on everything from tool wipedowns to light switches. Smells nice too..
Magnesium is difficult on the best of days:
http://forums.pelicanparts.com/porsche-911-technical-forum/1029154-fan-shroud.html
If you go to the pics, you will note the internal corrosion on the grain lines. Magnesium is doomed to return to its most stable state as soon as it’s poured. The aircraft industry keeps that herd of cats under control by rigorous maintenance schedules and life limiting parts made of magnesium. The Dow #19 process uses chromium and is not friendly to carbon life forms. Paint and other coverings simply don’t work long term. Which is why the aircraft industry use chromate conversion processes, prior to paint. Cerakote, powder coating and paint just cover up what is going underneath. Magnesium is maintenance labor intensive, with potentially dangerous processes. It’s still used because it is wicked light and crazy strong in the right application. I can honestly say I have never seen a magnesium propeller or fan blade in the aircraft world, but I bet there is one being used somewhere on something.
So the short answer is anything that will stay firmly attached to the surface of the magnesium that will keep water and air(w/oxygen) away from the unoxidized base metal is the answer. I hit my fan and shroud with ACF annually with a brush and occasionally spray some into the idling fan to protect the hard to get to points of the fan shroud components.
Cosmoline is probably the single best alternative, but it is messy and smells like azz for almost ever.