Alodine HELP!

Here is a question that hasn't been tackled:

I own an aluminum glider with discoloration on the aluminum along the cockpit rails. My best guess is that years of post-flight armpit sweat has put salt on the rails causing a little corrosion on the surface.

I'd like to alodine it as a base for grey primer.

1) How do I alodine a cockpit rail without getting the prep, alodine, or rinse all into the cockpit or down the side of the painted glider?

2) What masking tape could be used? (What is used on completed aircraft around Windows that stands up to all the toxic stuff during repainting? Foil tape?)

3) If I have to rinse the alodine afterward, can I use wet rags instead? It doesn't need to be pretty, just good sweat protection and a base for the primer?

4) Can self etching primer be put into the alodined rails?

HELP!
THANKS!

I spoke to a technical representative from PPG many years ago here in England - He said not to use an Etch primer over Alodined surface - The Etch primer is to etch the non treated aluminium - Not a surface that already have been converted by the Alodine process. Use Epoxy primer over Alodine surface - OR - Just use an etch primer on clean aluminium - Using Alumiprep to clean the alu first. Clean up the alu using alumiprep with maroon Scotch brite pads - Now you can Alodine or Etch primer ... both processes must have clean and oxidise free surface to give you best performance - I have made a 'bath zone' using duct tape and plastic to localize application of alodine - Then just rinse off

Agree with Jan. Either alodine or etching primer. Both are not needed.

If you really want to alodine, use light soaked cloth or paper towel to treat the area and avoid run-off. Let it sit on the area a few minutes, as you would if wetting. Remove and rinse.

Reinagreaves said:

1) How do I alodine a cockpit rail without getting the prep, alodine, or rinse all into the cockpit or down the side of the painted glider?

3) If I have to rinse the alodine afterward, can I use wet rags instead? It doesn't need to be pretty, just good sweat protection and a base for the primer?

Click to expand...

This might answer questions 1 and 3:
http://www.henkel-adhesives.com/com/content_data/131874_Alodine_1132_brochure.pdf

Literature says it covers 50 sq. ft. No rinse.

I may try alumiprep followed by my trusty Napa self etching primer. I used the stuff extensively when I built my Kitfox. It has been extremely durable. That being said, on the glider (Blanik), after scotch brite and acetone, it came off with masking tape! I am wondering if, even after my prep work, the aluminum had some contaminant that got in the way of a bond.

I may test this on a removed inspection panel for the forward tow release.

Reinagreaves said:

I may try alumiprep followed by my trusty Napa self etching primer. I used the stuff extensively when I built my Kitfox. It has been extremely durable. That being said, on the glider (Blanik), after scotch brite and acetone, it came off with masking tape! I am wondering if, even after my prep work, the aluminum had some contaminant that got in the way of a bond.

I may test this on a removed inspection panel for the forward tow release.

Click to expand...

Alodine is not durable with respect to physical handling. I use 2 pack etch primer - after Alumiprep .. and that is very durable ....