Originally published November 1996
Three Comments to Add to Charles Wagner's "Alodining"
1. Be sure to check with the local POWT (Public Owned Water Treatment) (sewage treatment) facility about the disposal of used alodine. Those persons living on U.S. government land (even civilians) are probably under the same EPA rules as civilian manufacturing companies. Civilian household waste falls under local and state laws. As an example where I work, one drop (that's all, one drop) of acetone in the waste water will be a violation of EPA regulations. At my house I could legally, but don't wish to, pour a gallon down the drain.
2. Alodine can be brushed onto the metal with a standard bristle or sponge paint brush. It will have to be rinsed.
3. I know people enjoy doing everything themselves, but let's be realistic. There are places that the homebuilt enthusiast can have alodining done relatively cheap in comparison to doing it at home.
More will be written in December or January (after the Flight Test Engineers Symposium) on corrosion control for aluminum aircraft structures.
Lee H. Erb
EAA Chap 1000 Det 5, Arlington TX
Thanks for writing, Lee. We discussed alodine disposal at the meeting, but it didn't make it into the newsletter. You are correct that this is a very important part of the process. I hate to think what the government would do to those of us living on base if they knew half of what we homebuilders were up to, which in the interest of the Fifth Amendment, I won't list here. For the benefit of all readers, this was the approved solution for disposal until somebody comes up with something better:
1. Let all of the liquid evaporate. This may take a few months. Feel free to use this time to prepare elephant stew.
2. Mix the remaining powder into a batch of cement. This is a good time to shore up those fence posts. Alternatively, cut the top off of a milk jug or other suitable container, pour in the concrete. Before it sets, knot both ends of a suitable nylon rope (1/2" in diameter or larger, about 1 foot long) and submerge the ends into the concrete to make a nice handle. Now you have some weights for clamping or holding those composite skins in place. Less messy than jugs filled with water.
We're looking forward to your promised article on corrosion control. This is an important subject that doesn't get discussed much -- ed
Related Article: Still More on Alodining