Re: Do I need to protect areas scratched on mast?
You should insert an aluminum compression tube through the mast. You can get a tube to fit diameter of through-bolt, drill mast to match OD of tube, have it welded in. Tube length should be same as original outside mast dimension. JB Weld will bring spar back to fair but will not address the compression. Without you are facing spar failure. Scratches can be painted with aluminum compatible paint (zinc chromate primer first), or a clear lacquer. We try to wax entire spar annually too.
BTW - is that a weld further up the spar? Might indicate a previous failure or repair.