I would agree with Brian, no aggressive chemicals should be used.Originally Posted by Brian Dick
Use red scotchbrite to get the crap out of the pores and prepare for refinishing.
In the UK, I use Liberon spirit based colours, I find mid oak/dark oak mix 50/50, works well.
Oil using RLO, first coat cut 50% with terps (the reduced viscosity allows the mix to penetrate) the terps acting as rapid catalyst and evaporating quickly.
This first step gives great depth to the final finish.
Follow on with neat RLO applications until it stops sinking in, wipe off excess and buff up to a lovely semi Matt finish.