If it was a freebee or really cheap and you knew about the defects, and you want to use the rod, here's what I'd do.
Wet sand the blank with 600 grit wet dry. Use lots of water.
Buy a plastic ketchup bottle from Walmart, or turkey baster, some UV Spar varnish from Ace Hardware, some thinner for the varnish, and a tack rag.
Sand the entire blank lightly including the guide thread epoxy.
It should now be a matte finish.
Now you'll need a place that's warm and as dust free as possible.
You are going to have to hang your rod sections to let them dry.
String taped to a broken rod section you might have lying around, will be inserted in the female end of the section or if it's a multi-piece rod, one for each section. If you have ferrules, tape them up with masking tape. If it's a tip over butt, I wouldn't worry about it. You can always wet sand or wipe off the varnish later.
Take some varnish and cut it 50% with your choice of thinner. Mix it up good
Pour it into the clean ketchup bottle.
Now get a roller paint pan and line it with aluminum foil.
(I've done this before in a stand up shower, and used string across the shower for a hanging line.)
Take the tack rag and clean the rod sections of any dirt, or other stuff that might be on it.
Now you'll get your thinned varnish and slowly saturate the rod section. If it's the butt section, grab it by the handle, tip end down, and turn the rod as you drizzle the varnish down the graphite until it's completely covered.
let it drip a little and then hang the rod piece. Do the same with the other section(s).
It will dry to the touch in a hour or so, and just let it hang and dry for a week or two before using.
Simple as that.
The varnish is so thin, it will put a thin flexable coat on the blank that will last a long time. Plus it smells killer when you open your rod tube.