Thanks. I appreciate it. Yeah, it was a drum sander. I've never used one so that's why I'm hesitant. The oscillating floor sanders are easy, but I don't know if they could take it down enough to get these gouges out of it. Guess they could but would take awhile.OC, from my 30+ years in the flooring business (not refinishing) what I saw most of on floors that were really bad was the big drum sander, like a belt sander on steroids. They would sand then use a wood putty as close as possible to the wood, but they were pros at it. We didn't do hardwood floors, we did carpet, vinyl, and tile. Towards the end of my flooring career they came out with the laminates, which they have improved since I quit. Wish I could help you more. My attitude now is, if I don't think I can do it, hire it out to the pros!
One the good side, with floors in a pre-Civil War house, they're plenty thick. Probably 7/8 or an inch.