Improving on your old wooden floor

If you think you can improve on the look of that old timber floor ,,,think again . Especially if someone else has already tried to cut and varnish it before.
-The dark stains where water has got to the wood must only be skin deep or they will show
Staining is very difficult ( even when using a stain in varnish- the best way ) because every brush stroke matters ( on the 110 sq metres I just did that's probably 110by 100= 10000 brush strokes (10hours of careful work)

Also feather to nothing  the edges,  or,  like me,  you will get most of it right and have your joins look wrong ..Suggest you do one complete board( max 2) at a time ie full length. The worst thing you can do as with most paint jobs is to brush over tacky areas . Itried sanding those mistaken darkened pieces but complete removal is required to avoid blotchy effects ( unlike the grain effects ). You can and often have to go darker than you would like,  which suggests a lighter first coat/ stain  is nothing to worry about .
 I knew it wouldn't be easy in my case because the baltic pine ( apart from being more valuable than the whole building ) was second grade and had lots of green on the edges ( lovely pinky red on inside ) making the pattern have too much contrast and darkness .Glad i didn't try to just "paint " them - days of work ! The one thin coat of jarrah varnish stain ( 5% could have been less )turned the green to brown successfully,  but only just .

Make sure you sand it back well at the start and don't leave the drum ver spin in one place. Most boards bend upwards so have to go across sometime to get all the cover off . Use course paper for a start as old varnish will clog up fine very quickly . medium seems to be the best finisher provided you don't want a surface like a mirror < use satin and good luck .