Sanding/Refinishing 100 year old Douglas Fir
Hey guys! hoping I can get some help (quickly, because I don't have much time to work on these floors :) ) We have 3/4" 100 year old douglas fir plank floors in our living room. They are dirty and gray for the most part, but parts seem to have a brown paint on them. I was working at getting the paint off with an orbital sander and 60 grit sandpaper, but it does not seem to be working very well and it's exposing a lot of new wood on the higher parts of the wood.
1) Is it safe to use a belt sander on these floors or will that ruin the wood?
2) What grit of sandpapers should I be using so that I don't lose the patina? I don't want the floors to look smooth and new, but weathered and old while still being attractive.
3) How much should I sand down to keep the patina? I am not exactly sure what I am looking for. Do I sand til the gray is all gone or do I just sand the gray bit smooth with a fine grain sandpaper?
Help me! :) Thank you!