I applied tung oil to a pine cookie and the sand lines from the drum sander became more visible. I usually re-sand with fine grit in my orbital sander but this time I must have omitted that step. I tried sanding after the tung oil application and, as I expected, the sand paper gummed up. What are my options other than using a LOT of sand paper? Will tung oil "harden" or become sandable over time? I applied the oil this AM and tried to sand this PM.