After searching far and wide for a stand-up diamond grinder rental in my area, I thought I was lucky to find an Edco unit (two 7" discs with diamond inserts), which I rented for the weekend. I was surprised at how little productivity I got from it. I wasn't expecting to grind down to the aggregate in nothing flat, but after eight hours, I figured out I only got 50 ft2/hr with only very light surface removal, and this doesn't count the areas against the walls, which I'll do later with a hand grinder. I also have a lot of areas I'll need to clean up with the hand grinder since the removal was close to nothing.
I've searched the forum and saw where someone used a field stone to weigh the unit down more, so I put a 60 lb. bag of sand on the front, and that didn't improve things much. I even sat on the sand bag and pulled myself along with my legs, and this helped a little (also helps with getting a sore backside...). These were for sure the diamond inserts and not the stone inserts. When I rented the unit, they also threw in the steel scrabbler discs, and those barely scratched the surface. My concrete is around 4 years old, standard power trowelled finish and no sealers, hardeners, etc.
I've read on the forum where folks have gotten around 50-100 ft2/hr by hand grinding. I'm thinking about just hand grinding in the future, since it's about the same production rate, and (hopefully) more agressive in the surface removal. Speaking of... Any thoughts on a good hand grinder? I've seen where someone had good luck with the Bosch. There's also Metabo and Hilti (locally the Hilti DG150 is $1100, plus a $500 power conditioner(?) -I know they make good tools, but wow).
I've searched the forum and saw where someone used a field stone to weigh the unit down more, so I put a 60 lb. bag of sand on the front, and that didn't improve things much. I even sat on the sand bag and pulled myself along with my legs, and this helped a little (also helps with getting a sore backside...). These were for sure the diamond inserts and not the stone inserts. When I rented the unit, they also threw in the steel scrabbler discs, and those barely scratched the surface. My concrete is around 4 years old, standard power trowelled finish and no sealers, hardeners, etc.
I've read on the forum where folks have gotten around 50-100 ft2/hr by hand grinding. I'm thinking about just hand grinding in the future, since it's about the same production rate, and (hopefully) more agressive in the surface removal. Speaking of... Any thoughts on a good hand grinder? I've seen where someone had good luck with the Bosch. There's also Metabo and Hilti (locally the Hilti DG150 is $1100, plus a $500 power conditioner(?) -I know they make good tools, but wow).