I have often wondered if it takes sandblasting with proper blasting media, to get into all the cracks and the bottom of weld-laps or pitted areas on aluminum spars.
It would seem to me that surface sanding on the aluminum, could leave v small corroded areas, which would later break out in more corrosion maybe even prematurely. Does an acid etch get to the bottom of these surface blemishes, satisfactorily ?
On SS fabricated parts we have been cautioned to use only un-recycled glass beads, for blasting media, could this advice be good for aluminum, too ?
My aluminum mast, spreaders, and boom were glass bead blasted, and painted with Awlgrip LPU .
I did have a spot of corrosion bubbling up the paint, and often wondered what caused it.
Sure the answer could be a missplaced finger print, a drop of water from the sky, ect., after the blasting, but before the Alodine etch could be applied, but are there a heap more answers that could apply, too ?
Douglas
