concrete grinders

[kaffine]

I need to grind a couple of slabs some before putting down VCT. I have 2 small rooms around 12x14 and my shop 28x28 to do. I can tear down the wall between the 2 rooms making it 12x28 if needed. The shop slab is in fairly good condition just a few high and low spots. The other slab is in bad shape and the concrete is weak, also there is also an adheasive residue I've used a scraper to get up all I could get with a pole scraper what is left isn't sticky.

Can 1 type of grinder handle both slabs or do I need to rent 2 diffrent machines?

My local rental yard rents Edco 7 inch 10 inch turbo grinders and a 22 inch dual disc grinder. Which would be easier for someone that has never used on before? I also have some concrete to practice on if needed that doesn't matter if I destroy it.

Do I need to rent a vacuum with it or does grinding it wet keep the dust down enough that the vacuum isn't needed?

Thank you.

 

[Big Boi]

I would like to hear some feedback on this as well.

 

[wbclassics]

When I was renovating / expanding my other home in 2004/2005, our dumb@ss concrete contractor dumped the excess concrete into the middle of the new 16x36 addition foundation. He tried to hide his stupidity by smoothing it out really well, so well that I only caught the mistake when I went to put the flooring down (6months later) at which time he pretended not to know who I was. The floor was 3/4" high in the middle of the foundation and that tapered off to level about 7 feet from that high spot, to the effected area was about 14x14. Walls were already up, and I remember the framing contractor making a remark about the foundation levelness at a certain point, but I guess I was too busy to investigate further then.

The rental shop first rented me an Edco grinder that took six grinding bricks that installed on two rotating pads on the underside of the machine. I used the machine for 30 minutes and took it back, no way was this going to remove 3/4" of concrete. It'll easily knock down small and medium high spots on an otherwise level floor, but no way was it going to work for my issue. I had the roughest grinding media they had available in the machine.

They didn't charge me for that rental and then gave me a concrete scarifier... which worked perfectly and quickly. Removed all the concrete I needed, except the carbide teeth left tracks in the floor which would have to be filled in. So you have to go a little deeper so that you can get a perfectly level / smooth surface again with floor levelling material.

Neither one can get right up next to a wall. You'll have to use an angle grinder with a masonry disc to work in corners and next to walls. Both were extremely dusty, I don't believe either had a vacuum port on the machines I was rented. Both were relatively easy to use, I had never used either machine before, and had no issues.