problems with floor prep before epoxy, diamabrush

[ryan1000]

I used the diamabrush for about 7 hours on 475 sq/ft . I'm still far from bare concrete. I have some kind of black layer under the epoxy that takes forever to get off. Some areas are .040 thick. I do have a basement under the garage so I'm not sure if the black coating has something to do with that.

I cringe at the idea of renting the diamabrush again and working all day on it. Any ideas of how I would turn out with primer or patching followed by epoxy-coat and a clear coat? End result doesn't have to be perfect but I don't want it to look bad either.

Please take a look at my video and provide feedback. the video kinda focuses on the bad areas however most of the floor is smoother

 

[gregtwojeeps]

No good news from me, sorry. You needed a more aggressive grinder and cut that puppy down fast. You have a lot of what looks to be surfacer type patches that will de-laminate and cause you problems regardless of what type surface you choose to put on it....

If your tired of working on it and money is tight, just scrape the loose stuff off and roll on a garage epoxy. It will not stay on it like it should though because prep for epoxy is stringent and must be right.... The lay down mats might work on what you have showing right now...

If you are not tired, and have the money to spend, rent a professional grinder, a dual cutter wheel from a contractor's rental store and get it down to good concrete. About $300 a day... Then you can epoxy it, tile it, just use a densifier, whatever. Just do a search, this forum is full of ideas. Good Luck. JMO

 

[ryan1000]

The edco grinder is available for me locally. I was under the impression the diamabrush I rented was on the same level.

I want to go the epoxy route because I want the floor well sealed since there is a storage area under the garage

 

[ryan1000]

any other opinions, here are some more pictures

 

[workhurts]

Not much help here but if you can chisel it out by hand, how can whatever diamabrush you're using not just eat through that. I'd say, **** it up and get something more aggressive to take it off properly.

There was a post on here of someone doing it by hand with a dewalt grinder and shopvac of some sort. It looked pretty aggresive.

 

[leeklm]

By no means a pro here... just look at my previous post

I used a diamond cup wheel on my 4" grinder, and it will really tear the concrete down. You could get one for a 7" grinder and do the bad spots by hand. Be sure to keep it flat!! One of our area home depots had a floor machine with a 10-12" diamond cup that while slow, takes a lot more surface off than the diamabrush does. While I only used it once on old concrete, i did not care for the diamabrush.

BTW, you definitely want the vacuum dust attachment on your hand grinder when using the diamond cup wheel!!