Freds 73 Scamp restore on a budget

Still use the epoxy primer. All the alodine does is create a thin anodizing etch to the metal. But it does have chromates in it. Kinda toxic to work with , and has to be rinsed with water, adding to the toxic hazard.

The industry is now going with a non toxic product called PreKote to replace alodine. You basically spray it on the bare aluminum, and lightly scrub it with a fine scotch brite pad to agitate it for about 10 minutes, then rinse with water, and reapply a second time. After the second application of Prekote, sufficient dwell time and a thorough water rinse, you do a water break test. The water will try to pull away from a prekote treated surface. Not like water beading up on paint, much more subtle, but the water does try to pull away. This means the aluminum part is coated. This product is as strong as Alodine in preventing surface corrosion on aircraft skin, and is not toxic. You still want to epoxy primer over it to protect the metal well.

Also make sure your chemical paint stripper is thoroughly neutralized before even messing with anything else.

We had a fleet of SAAB 340B airliners that a paint shop contracted to do mtx on. They neglected to fully neutralize the chemical stripper on 2 aircraft but didnt remember which ones. The stripper kept eating the aluminum under the new paint. We had to bring in every one of em several different aircraft each day, and strip squares of paint in key locations on each aircraft inspecting the skins until we found the 2 aircraft in question. We ended up stripping them of useful parts and scrapping them.