How To Level and Polish Concrete

Thursday, 20 May 2021

How To Level and Polish Concrete

Here at Abrasives World, we can help you achieve a polished concrete surface with a variety of finishes from a matt satin effect to a glossy mirror-like finish. The finish of the surface can also be controlled by different levels of polishing materials. Polished concrete has been popular in commercial buildings for many years because it is very easy to maintain, however more recently with the interest in programmes such as Grand Designs it is becoming popular in private residences. Maintaining the surface requires dust mopping and occasional use of a cleaning product.

In simple terms, polishing concrete is similar to sanding wood. The use of Heavy-duty polishing machines or handheld equipment that is equipped with progressively finer diamond-impregnated segments or disks are used to gradually grind down surfaces to the desired degree of shine and smoothness.

The Polishing Process
The process begins with the use of coarse diamond segments bonded or welded into a metal disk. These segments can be coarse enough to level a a rough surface and then remove minor pits, blemishes, stains, or light coatings from the floor in preparation for final smoothing. The initial surface will determine the processes required the initial rough grinding is generally a three- to four-step process.

The next step will involve increasingly finer grinding of the concrete surface using diamond abrasive. The use of these increasingly finer grades of polishing disks (known as Lapping) will be required until the floor has the desired sheen. For an extremely high-gloss finish, a final grit of 3000 may be needed.

You can polish concrete with both water lubrication (called wet) and a dry method with no liquid involved. Although each has its advantages and disadvantages, dry polishing is dusty and will require extraction, whereas wet polishing uses water to cool the diamond abrasives and eliminate grinding dust. The water will extend the life of the disks and tooling due to reduced temperatures and lubrication, however this can leave a slurry that will need to be removed.

 

 

Right then now you're all ready let's have a look at a how to …...

Starting with a reasonable surface here are the products available for the first stages and some notes on usage.

 

Diamond Grinding Discs: Double Row 

Double row of diamond segments for fast, controlled grinding.

Available in 115mm, 125mm and 180mm. Use 180mm for 230mm angle grinders.

Open segment layout reduces risk of loading/clogging.

Generous 5mm deep diamond segments for long life.

 

Diamond Grinding Discs: Turbo SegmentedView

Turbo segmented making it easier to achieve a smoother result.

Suitable for harder stone types, granite etc.

5mm deep diamond segments for long life.

100mm and 115mm have integral M14 fixing nuts. 125mm and larger sizes have 22.2mm centre bore.

100mm has M14 Fitting for 115mm and larger grinders (ie not suited to 100mm angle grinders with M10 fitting).

Use 180mm size on 180mm or 230mm angle grinders.

 

Diamond Concrete Floor Grinding Discs: L SegmentView

Long diamond segments help achieve smooth results.

Open lay-out resists loading.

Can be used wet or dry.

6mm deep diamond segments for long life.

Sizes 125 and 180mm fit industrial grinders and floor grinders, sizes 125, 180 or 230mm.

Size 150mm fits Hilti DG150 floor grinder.

 

If you need to remove more material, bitumen or glue then these will be required to ease removal as they are less prone to clogging and fast removal of material

PCD Floor Preparation Cup DiscsView

Uses polycrystaline diamond (PCD) tips for performance and durability.

Generous PCD tip count for rapid action and longer life.

Fits standard angle grinders and floor preparation machines with standard 22.2mm flanges.

Rapid removal rate, (wear eye and dust protection).

 

Diamond Floor Grinding Plates - 250 mm.View

Fits most 250mm floor grinding machines (If hiring, check machine is supplied with suitable adaptor plate.)

Suitable for medium and hard surfaces, such as concrete with hard aggregates.

Colour may vary (these are not colour coded for hardness as they all cope with medium-hard surfaces).

Diamond Segment Depth: 9mm.

Checking your size: The 4 inner holes are on a square of 48mm side. (Your machine may need the correct adaptor plate.

250mm PCD Floor PlatesView

Fits popular 10in or 250mm floor preparation machines.

Uses PCD (Poly-crystaline diamond) in large segments to give exceptionally hard wearing tips.

16 PCD tips.

9 Holes (1 centre parallel sided. 8 countersunk).

Suitable for anti-clockwise running when looking from below at the working face.

 

 

So that’s the surface flat and even and ready to polish, we have below some selected products that will give you the required results

Diamond Polishing Pads - Wet UseView

Premium grade pads with high performance diamond grain.

100mm diameter (4").

Generous 3mm depth of usable diamond pad for longer life.

Grades from 50 (coarse) to 3000 (ultra-fine), plus white and black buffing grades.

9 disc set includes all grades, 50, 100, 200, 400, 800, 1500, 3000, white buff, black buff.

Water cooled, the surface should be kept wet.

Use at approx 2,000 - 2,500rpm for best results.

 

Dry Use Diamond Polishing PadsView

Premium grade pads with high performance diamond grain.

Size 100mm (4in).

Grades from 50 (coarse) to 3000 (ultra-fine), plus white and black buffing grades.

9 disc set includes all grades, 50, 100, 200, 400, 800, 1500, 3000, white buff, black buff.

Air cooled by rotating action.

Use below 4,000rpm for best results.

Designed for dry use, but also suitable for wet use where situation permits use of water.

Loop grip backing.