Replies

1. 
   mgard38 | Feb 26, 2010 08:01pm | #1

   I dont know were you live but look up a tool rental place like sunbelt rentals or similar thay rent concrete planers and grinders. A grinder will work if the slab is inside and a planer will work if in a well ventaded place.

2. 
   DanH | Feb 26, 2010 08:47pm | #2

   You need to be a little careful about the tool you pick -- many of the grinders are really intended only for rough work, when you have to take down a high spot by an inch or so, eg.

   Used to be you could get a hand grinding block -- basically just a chunk of special concrete with a handle attached.  Would work well if you only have to take off a few trowel marks.  Don't know if they're made anymore, though.

   And if you only had a very little to do you could probably use a grinding attachment in a MultiMaster.

3. 
   davidmeiland | Feb 26, 2010 09:49pm | #3

   You can probably find someone to come out and grind/polish your slab for you. Medium and large markets usually have companies that do slab sawing, core drilling, and slab grinding. They'll bring a big machine and hopefully some expertise to avoid putting marks in the slab to replace the ones that are ground out. It's not easy to do what you want with a small tool, especially if you're going to put a glossy finish on it. I have all sorts of grinders, diamond cups, cones, etc., and I wouldn't attempt it unless I could easily afford to fail.

4. 
   popawheelie | Feb 26, 2010 11:44pm | #4

   I've ground down small defects in conrete using a block like a cinderblock.

   I also used some muriatic acid to soften it up a bit.

   As you rub the block back and forth it will create a slurry.

   I used knee pads and both hands. It is phisical work.

5. 
   sunsen | Feb 27, 2010 04:40am | #5

   Thanks for the advice everyone. The hand "sanding" block sounds like the ticket. I'm aware of how difficult it would be to do this with an electric grinder without making things a whole lot worse. I haven't seen one of those blocks with handles before but I'll head on down to the concrete supply house and ask about.

6. 
   Kevin_D | Mar 02, 2010 01:18pm | #6

   There are a variety of grinders for Concrete. 

   There are large floor grinders and small handheld grinders.

   I did a google image search and found them in about 2 seconds: 

   Here are the pictures for you.

   Large :  http://www.mikes-rental.com/Pics/Pics/Concrete%20Grinder%20Small.jpg

   Small:  http://www.thegeneralrental.com/rentalcatalog/images/grinder_hh_surfacer.jpg

   You can also get handheld blocks for minor stains etc.

   Check out Fu-Tun Chengs "Concrete at Home" for some tips on using these, or another quality concrete book.

    http://www.amazon.com/Concrete-at-Home-Fu-Tung-Cheng/dp/156158682X/ref=sr_1_1?ie=UTF8&s=books&qid=1267553416&sr=8-1

   I like Fu-Tung Chengs book as an example, because he does very high end finish work and grinds a variety of aggregates and finishes.

   Edit: Sorry forgot the hand held diamond pads  http://www.amazon.com/Diamond-Hand-Polishing-Pads-Stone/dp/B000UGJUDW

1. 
   popawheelie | Mar 02, 2010 01:39pm | #7

   I think you are right about a grinder working fine. It sounds like the OP just had a few to take down.

   The angle grinder should work fine.

   I think using the angle grinder would be like some other tools.

   Like a big belt sander. Go easy at first to get the feel of it.  Stop once in a while to look at what you are doing. Don't bear down on one side or you will get marks.

   I guess for some tool users it would be intimidating and they might not have the skills.

   I've always started slow and easy with a new tool to get the hang of it. Works for me.

2. 
   sunsen | Mar 03, 2010 10:42pm | #8

   Hey thanks Kevin. I have several grinders and the link to the amazon page gave me the idea of buying the proper diamond pad that will fit one of those things.

3. 
   DanH | Mar 03, 2010 10:47pm | #9

   I haven't been able to find a decent grinder since I left the east coast.