Today I used a buffer equipped with one of those copper plates, to clean up the paint overspray, morter residue, etc, left on new construction My question, Do they wear out? It was on the shops machine, so I have no idea how old it is, and the last time someone used it, they used a 20 grit disc over it. I thought it would cut faster. I sure like the idea of not hand scraping while prepping concrete floors.

I also rented a big Eddco surface grinder to attempt to take care of some high spots. Came with stones on it, and wasn't as aggressive as the rental guy led me to belive. Would a scarify(er) have been the better choice? I had an area about two feet wide, about 6 feet long, that was 3/8 too high. Gave up on the surface grinder, and used self leveler. Grinding still would have been better; what should I have used? Or how should I have gone about it?

I just use a hardplate and some tuff paper.

And tuff paper would be..... 20 grit? Yeah, I'm a dope!

I've tried to knock down high spots on concrete with real coarse sandpaper (16 grit) What a waste of time! I've heard grinders are the way to go. But the dust! Ugh! I avoid slap prep that requires that much detailing. I'll just sub it out and do what I do best, lay floors. Did you consider dynamite?

the problem being that, when installing for a shop, I don't see the job beforehand, then I find what the salepeople don't want to see, and if I pull off, I can lose at least the rest of that day; or maybe the rest of the week.

Yeh, I understand! Ya gotta do what ya gotta do! Do they pay you decent to deal with that? I'll bet they try to talk you out of doing that much prep, saying it isn't that bad. I know when I've subbed for shops they always tried to cheap out on the prep and tried to get me me to cut corners or eat the prep. I got so fed up with that BS that I stopped subbing except for a select few who know where I stand. Now, I don't get many calls for subbing but I'm not doing any prep for free either.