Grinding Concrete Floor

I want to take a layer off of my garage floor in prep for painting it. I tried a chemical wash and power washer but it was just taking too long and it will take forever to dry in this weather.

I looked at Home Depot, and they suggest this machine:

http://www.homedepot.com/hdus/en_US/DTCCOM/HomePage/Tool_Truck_Rental/FloorCare_Sanding/Body/Images/TTR_FL_Body_floor-maintainer.jpg

Just a regular floor sander but with a different pad.

Who has done this? Where did you rent the machine?

Just looking for some more info, because no one I know has done it or does it for a living and maybe I could hire them.

in for results

Also in for results.

I was looking into this a couple days ago for my basement. But then I said f it and just painted it without sanding. It turned out OK but now I wish I sanded it.

Is your goal to get better adhesion by roughening the surface? Is it currently a broom finish or troweled?

I had a project with all exposed concrete floors that were seriously messed up during construction. It was high PSI concrete with a trowel finish. In ord to get anything to stick to it they ended up having to acid etch the floor…twice. The first time the coating stuck okay until some heavy rolling loads went over it and then it all popped up

Acid etching is a nasty process but effective on a hard troweled slab. if you have more of a broom finish I think the heavy duty sander should be plenty effective

In for results!

Its a trowel finished garage floor, that is many years old. My goal is to get the grease, oil and other contaminents off of the surface of the floor. Not all parts have stains but about 40% of an 800 squ. ft garage do.

From my expierience acid etching really isn’t too bad. Although commercially they probably use harsher chemicals.

Let me tell you what I have done so far.

After sweeping I let some run of the mill concrete degreaser soak in, gave it a scrub and power washed. Most of the grime was removed, but it was a slow process.

I bought acetic acid because I planned on doing a chemical etch before applying the expoxy. I decided I’d give this a try because according to the bottle you can use it for cleaning as well. Pour some on, let it sit, then power washed. This worked much better and I was able to move much quicker. Still I am not convinced I am getting all of the contaminents out. The water still beads up in some of the spots that I have cleaned so I know there is still some stuff in the floor.

Thats where the grinder comes in, if I can take a thin layer off the top it will give me a new surface to work with and also I will avoild adding a ton of moisture to my garage. Most likely I will still do the chemical etch with acetic acid before I lay the paint down.

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ABC rental seems to have a good machine.

Interested in the results as well

Schuele paint rents the machine as well if you’re in buffalo. Call the summer st location downtown buffalo and ask for Nic, tell him Ryan said to call. I use to work there. 884-3374

I used one of those when I worked at circuit city to attempt to remove epoxy. IT SUCKED. There are other members on here that can attest that it took us two days of no stop use to grind out 3 bays and we were using whatever special diamond stone shit they made us buy. We never did remove all of it but we decided that what it couldn’t remove would never be removed by a car tire so we epoxied over the top.

I can also recommend buying a 55 gallon drum of corn syrup…it will eventually eat away the top layer of concrete…watch out for bees

Which machine are you referring to the Home Depot one or the one from ABC Rental.

I have heard a floor buffer with a screen pad is the best method for sanding a floor. I finished my floor in my basement but will be redoing it in some areas because of some changes I want to make. I was planning on going this route.

I’d suggest giving it a go so long as you are not grinding down 1/2" of concrete in areas to make it even. This is more to expose the aggregate in order to re-seal.

Okay. Good to know and like stated before I’m not looking for my floor to get smoother just to have the top layer of set in stains removed thats it.

I like exposed aggrigate.

What did you use for that?

I’m very torn at the moment. The floor isn’t in super great shape so I’m wondering if its worth doing all that work for the epoxy.

My other option would to just clean it up and paint it with regular paint. To make if worse I already have the epoxy.