I've had a very busy three days sanding down this concrete floor. It was very bumpy and covered with goo in the beginning. The floor had been covered in carpet that was glued down. There were many spots where the concrete had been patched in the past.
The owner had considered putting down new carpet or putting some sort of interlocking flooring. The option chosen was only slightly more expensive and it will last longer than he will.
This Husqvarna floor planer has diamond impregnated disks on the bottom. It's a very heavy and powerful machine.
I made a few alterations to the machine to make it more functional. The cord comes out behind the machine, in a manner that allows it to be walked on or run over when you're backing up. I threaded the cord through the body of the machine and taped it to the left handle, pointing away, so that it would now run along the side when I make trips back-and-forth. The front bumper was quite scratchy so I covered it in thick, slippery tape.
When a bump is encountered on the floor, the machine tends to grab hard and it can throw the operator. My friend who is older and skinnier than me, tried to use the machine, but he was thrown around like a rag doll.
I'm glad he tried it early on because in the one minute of use, he put four bad gouges in the floor. They were sanded out and there is no evidence of them now.
It's all done now. The office will be put back together later today.
The portion to the left, in the fourth photo, was much higher originally. When it was ground down, this exposed the larger rock below.
My friend wasn't concerned with having an absolutely new looking floor. He realized he's working with 100 year old concrete.
Although it was a hard slog, this method of finishing a concrete floor, uses far less resources than any other method that I know of. We used one gallon of water soluble finish and we used so little of the diamond disc that they didn't charge for it.
Two days after the grinding process, I still had sore pectoral and abdominal muscles.