Brief Description: Priming the horizontal stabilizer parts - part 2
I had 18 parts total to prep and prime today. Two big skins, six nose ribs and 10 inspar ribs. The skins were prepped using Prekote and ScotchBright like all my other parts so far. For the smaller parts I wanted to try the etch and Alodine prep to see if it's easier.
I set up three basins and a couple of 2.5 gallon zip-loc plastic bags. The first is a soap (Dawn) and water wash. The second is a rinse for the Alumiprep 33 acid etch and the third is a rinse basin for the Alodine. I used Alodine 1200S. There are a lot of different types of Alodine (Bonderite) and each is used for a specific metal. I bought the 1200S before I did any research. The process specs at work have the answer, so I'll need to read those. In the meantime I pressed ahead. Hope I made the right choice for 2024 clad aluminum.
Alumiprep 33 is diluted three parts water to one part Alumiprep. Alodine is two parts water to one part Alodine. Pop the part into the bag and agitate for about 2-3 minutes (the instructions were strangly silent on the amount of immersion time). The test is a water-break free surface, which is what I got so a couple of minutes seemed fine. Rinse with water then into the Alodine bag for two to five minutes. I did 2:30. The Alodine lost its effectiveness after about six parts. The sixth part was noticeably a lighter gold color than the first, so I mixed another batch of solution. Three batches of Alodine later and everything was a nice gold color.
Into the spray booth for a coat of green primer and it's all done. I did a much better job this time with no runs or missed areas. Experience helps. After it cures overnight I'll try to get all the riveting done tomorrow.
Was this process easier? Yes, but less than I thought it would be. I need to dispose of all the hazardous waste at the local waste station.
Left to right: Wash basin, then Alumiprep 33 acid etch, then Alodine.
Using a 2.5 gal zip loc bag uses less product than a basin. Agitate the part to get full coverage.
Alodine process finished. The different shades are due to the Alodine becoming less effective.
