The authoritative public forum
  for Metal Finishing since 1989
-----

Powder coating vs. aviation gasoline

January 22, 2011

I'm replacing the gas caps of my vintage 1947 Stinson 108-2 aircraft. The replacement parts are of aluminum (alloy unknown) and MAY be clear Alodined. The filler neck mounts are drawn steel, alloy unknown.

Is powder coat insoluble in 100 Low Lead aviation gas? Insoluble in 90 Octane no lead/no alcohol auto gas? Does the pigment used make any difference? (I want a bright yellow on the aluminum and bright red on the filler neck for contrast - the red is hidden when the cap is properly installed)

Exposure for the aluminum parts will be the occasional splashing and handling wet during the tank filling operations. The steel parts may be partially immersed (full tank condition) for extended periods of time. The aircraft is kept in an unheated hangar; temperatures can range to 40° C, but direct sunlight exposure occurs only when the aircraft is actually in service.

What sort of powder coat(s) do I need to specify for this application? Surface preparation required for both metals?

Eric Schlieper
Aircraft owner/restorer - Toronto Ontario Canada