Options for sanding a concrete slab

[Beltis]

Hello,

I plan to finish a table with a concrete top towards the end of summer. The production of the top is under control, but I have a few thoughts on how to go about polishing the top.

I've been lurking around the internet, and there are a few ways to go.

- Polish by hand
- Order a simpler machine from eBay - wet polish grinder
- Rent a machine when needed
- Buy a better used machine, for example, Flex 1709.

Initially, I want to finish the tabletop and have ambitions to make some other tops in the near future.

The budget is decent, mainly want a good result.

What tips you do have?

/S

 

[Montören]

I just received my wet polish grinder from England today, haven't had the chance to test it yet.
(need to fix the water connection first)
I will be grinding concrete countertops, will update once I've tested it!
Cost 1900kr including shipping and an extra set of grinding/polishing discs from Amazon

 

[Beltis]

What timing. I've been looking at similar machines myself. Have you tried any other form of concrete grinding before?

 

[Buuzzz]

I made a small table with a concrete top that I polished with a Flex. (The first step I polished with a Festool sander with a diamond cup) I used HTC's grinding system (7 steps) I used fine concrete (not a good result, too much small gravel appeared during grinding. I only wanted "large" stones to show up during grinding...) I should have used pure concrete and thrown stones into it, I think. New attempt in the fall. I can post some pictures when I get home.

 

[Montören]

Now I've fixed the water connection and tested sanding a little bit.
I sanded with the 400 sanding block in the picture, and I also saved some of the raw concrete.
It went very quickly to get the surface smooth. I cast with Finja fine concrete so it's the aggregate you see in the picture, not pores.
I have quite a lot to cast for my kitchen, so I will make my own thread about this when I start.