Alodining pain

[plhamilton]

I am interested in seeing how many people stopped using alodine once they got to the end of the tailcone... If you decided to stop, I would appreciate a simple statement of why... Also interested if you decided to go to a commercial operator to do it for you... Thanks in advance.


Cheers

Paul

 

[Auburntsts]

I stopped, well sort of. I wasn't actually using Alodine but another chemical conversion process, but the end result is/was supposedly the same (time will tell). Anyway prepping and priming (I used Stewarts water based epoxy primer-sealer) takes a lot of time. I primed everthing in the tailcone. When I got to the wings, I prepped and primed the ribs and only the rivet lines and overlap joints on the skins. With the fuse I didn't prime anything but skin overlap joints and I did that with a rattlecan.

If I had to do it over again, I'd only prime the faying surfaces throughout the kit. YMMV....

 

[J Twilbeck]

Applying a chemical conversion coat such as alodine requires prepping the aluminum with an etching acid. The process removes the pure aluminun clad surface that almost all parts of the kit are made of. The clad surface is naturally corrosion prohibitive which make applying alodine to a clad surface basically a fruitless effort. You're removing a corrosion prohibitor to apply another. Still, all bare aluminum parts should be alodined to apply the surface treatment.

.....priming on the other hand may still be required but we won't get into that.

I have only alodined bare parts since day one and am still alodining only bare parts now.

 

[Auburntsts]

Applying a chemical conversion coat such as alodine requires prepping the aluminum with an etching acid. The process removes the pure aluminun clad surface that almost all parts of the kit are made of. The clad surface is naturally corrosion prohibitive which make applying alodine to a clad surface basically a fruitless effort. You're removing a corrosion prohibitor to apply another. Still, all bare aluminum parts should be alodined to apply the surface treatment.

True. But you left out some info as why anyone would want to alodine to begin with--2 main reasons: durability and a better paint substrate. The Alclad layer is extemely soft and easily damaged. Removing and replacing it with a chromate coversion layer produced by the alodine provides a more durable protective coating, even if scratched (to a point). The etching the provides a much better substrate for paint adhesion than a smooth Alclad layer. Note: if you use a self-etching primer, you are damaging the alodine layer and defeating the purpose.

IMO, if you aren't going to prime, there's no reason to alodine as you pointed out. I'd either just use an alodine pen and/or a shot of rattle can epoxy primer on any scratches or areas where the alclad was removed.