While down in Adelaide recently I called in on SAAA member, Patrick, and borrowed his long alodining bath, so tonight I thought was a good time as any to treat the front/rear spars and spar doublers.
First I rubbed each part down with isopropyl alcohol, and then filled the bath with Alumibrite acid etch and immersed each piece, one at a time, for one minute. After a rinse with the hose I carefully set the parts aside as I swapped out the Alumibrite for a tank full of Alodine.
Each piece then got five minutes in the Alodine before another rinse off under the hose. I then set them all aside to air dry.
I found it very difficult to handle the long parts without rubbing off some of the wet alodine in a few spots (see picture below)
Also, the whole process of treating just six pieces took me 2 hours. One bath is not enough so for future long pieces I think I'll set up several baths so I can quickly move the pieces from one to another without having to empty and refill the one tub. I have some lengths of PVC guttering which I'm hoping will do the trick.
I'll leave the newly alodined parts to properly dry over night and them give them a coat of epoxy primer tomorrow. Once that's done then it's time to start rivetting!
Front and rear spars and spar doublers now alodined
Some alodine rubbed off while trying to handle the parts
