Jonny C
Member
I just spent 3 days on my knees Scotch-Brite scrubbing aluminum parts with Deoxidine (a mixture of phosphoric acid & solvent for removing oxide and oil residue). It's wasn't fun.
Formed parts like ribs and L angles aren't easy - it takes time and it's sometimes difficult to get in all the internal angles. After this process, I prime with Stewart Systems EkoPoxy (great stuff but not self-etching).
I've got loads more to do and was wondering how manufacturers prepare their aluminum. They can't be doing it manually but I am wondering how they ensure paint adhesion without scrubbing.
I found a video of Piper doing prep and their process is to wash the parts in soapy water twice and then rinse. Next, the parts are dunked in an acid bath to prep the surface for a coat of 2-part primer.
Are they able to avoid abrasive scrubbing because their acid is much more concentrated than the stuff homebuilders use? Are they using a self-etching primer that will stick to a fairly smooth aluminum surface? Does using hot, concentrated acid mean that the surface is etched well enough for a non-etching primer?
Does anybody know the process that other manufacturers use? Is there a way, at least for the smaller parts, that a homebuilder could clean with an aviation detergent, then submerge them in an acid bath and avoid days of Scotch-Brite abrading?
Formed parts like ribs and L angles aren't easy - it takes time and it's sometimes difficult to get in all the internal angles. After this process, I prime with Stewart Systems EkoPoxy (great stuff but not self-etching).
I've got loads more to do and was wondering how manufacturers prepare their aluminum. They can't be doing it manually but I am wondering how they ensure paint adhesion without scrubbing.
I found a video of Piper doing prep and their process is to wash the parts in soapy water twice and then rinse. Next, the parts are dunked in an acid bath to prep the surface for a coat of 2-part primer.
Are they able to avoid abrasive scrubbing because their acid is much more concentrated than the stuff homebuilders use? Are they using a self-etching primer that will stick to a fairly smooth aluminum surface? Does using hot, concentrated acid mean that the surface is etched well enough for a non-etching primer?
Does anybody know the process that other manufacturers use? Is there a way, at least for the smaller parts, that a homebuilder could clean with an aviation detergent, then submerge them in an acid bath and avoid days of Scotch-Brite abrading?
