old jarrah floorboards

maybe this should go in 'Finishing'

scenario. large dormitory style building, besser brick walls, jarrah floorboards about 40 years old. I suspect these were nailed down and never treated sealed with anything.
I was going to start banging the nails deeper and run over with a scrubber or sander. but stuff that, leave as is but throw down linseed/kero ? mix.
After Easter I will try a couple of litres in one corner but am concerned about how thirsty these boards will be and after all this time giving them a drink can I expect and trouble....... PLEASE PLEASE SAY NO :rolleyes:

thoughts suggestions how fast should I start running

I had a similar challenge a few years back, Tony.

House built in 1880's had Tas Oak floor, mainly messmate, over extremely hard joists - Tas blue gum (E globulus) or spotted gum (maculata). We remove old carpets and antique lino and found the apparently untreated floor.

Asked a professional floor sander for advice. He put a straight edge over the floor - very minor cupping was visible. He said he could easily sand the floor flat but "would you want a floor that looked visibly new in a 100+ year old house? If we stop sanding before all the old surface is removed then we will have a striped floor - stripes of new timber and old timber." He advised us to drive all nails, if possible, and then to sand the floor with a ROS until it looked clean but still showed the signs of its lifetime. We tried driving the nails with a punch and a 5 pound hammer and also with a pneumatic hammer; neither really worked; the timber was just too hard. It was just impossible.

So we sanded the floors with the Festool ETS 150/5 ROS running through grits 80, 120 and 200, until the floor looked OK. Most nail heads proved to be slightly below the surface of the timber. The we filled all holes and all nailholes, including those apparently flush with surface. When cured, a final sand with 250 grit in the ROS, and three of coats of gloss urethane.

I never even considered the possibility of the floor moving with sanding/finishing work on it. After 120+ years it should be stable...

Your floor has been air drying for 40+ years, so it also should be stable. And high gloss jarrah just looks so good.