Re sanding and sealing a wood floor

Hi all, I hope you can help: about 10 years ago I resanded my wood floor. Apparently it's American white oak, and it's laid in strips about 60mm wide and about 5-8mm thick. Straight after sanding it looked great. I then gave it 3 coats of what the hire shop told me was clear sealant (oil based I think), which turned it from a sort of yacht white to a sort of um... yellow.

It's beginning to look a bit tired so now I want to resand and coat it with something that will be hardwearing, as I don't want to do it again, and bring out the real colour of the wood. Obviously I don't want to take off more wood than I need to, but I've heard that finer grit papers become clogged with old varnish very quickly, and I don't want a horror story on my hands.

If anyone has an idea how I should proceed regarding sanding and sealing I would be very grateful. Bill

You'll have to remove all old finish material. Start with grit 80 to see if that does the job - if not, then sand with grit 40.

Finish with grit 120 if you want to apply hardwaxoil or with grit 150 is you want to apply varnish or lacquer.

Oak does turn 'yellow' - honey colour - over time, it's a characteristic of Oak.
Normal, proper sanding takes off 1 - 1.5mm of the surface

Thats great, thanks a lot - although which would you recommend to seal and preserve the original colour? I can't see the job being done again in my lifetime, and we want to preserve the original white oak colour as much as possible. Bill

HardWaxOil natural would be our choice.