Dishwasher rack tines break off or lose the protective coating at the tips and then you get rust spots on your dishes. New racks cost about $80 (and up). But you can fix yours in less than an hour and for a fraction of that cost. Buy a bottle of vinyl repair paint and a package of replacement tips to match your rack color (from any appliance parts store or find-a-fix.com). Cut off the rusted tips with a rotary tool and cutoff wheel. Then retip the tines (Photo 2).
To patch a rusted area around a broken tine, first clean off the rust (Photo 1).