Originally Posted by dabac

Re: etching
Aluminium spontaneously react with air by forming an oxide layer. Getting stuff to bond well to that layer is tricky. The etching is supposed to remove that oxide layer to let whatever you’re applying bond to truly bare metal.
One option to etching is to mix up a small batch of resin, then use that to wet sand the area about to be treated. The sanding breaks through the oxide simultaneously as the resin fills in the scuffs before the metal has had time to re-oxidise.

I think you’ve done a good job and I would be quite content to ride a bike with that kind of repair. A good amount of overlap.

Me, I might have tried to get away from that huge chunk of filler some way. And maybe cut the CF more at a taper the whole way to create a smoother transition from the aluminium to the repair and back to the aluminium.
Not that I think it’d be hugely important.