Use a skew for the final pass.
Red oak has open grain, and getting a really smooth surface requires additional steps. One option is to sand with medium CA so that the sanding dust will be forced into the pores of the wood - that would be ideal if you are using a CA finish.
I don't care for a CA finish, so my preference is to smear some wood filler over the turned piece before finish sanding, and then several applications of sanding sealer, sanding between applications. The final finish is then either a lacquer-based friction polish or WOP.