Originally Posted by 909
A corner needs to be filled , sanded and painted.
Which brands work?
And which don't.
Cosmetic or taking any kind of load?
Personally, my default would be P40 fibreglass filler. Most wood fillers are mostly designed to absorb stain rather than be resilient.
Only concern would be going back to what sort of stresses would it be under as you mention a corner? P40 is still going to be about as good as it gets but even that has its limits.