Polishing concrete is a specialized technique that undergoes a multi-step process to achieve the desired quality. The process involves the use of adequate tools and equipment. A well-polished concrete floor should have a glossy and mirror-like finish. You can have a variety of options to choose from when polishing your concrete.
You can have any colour, design using saw cuts, and embed aggregates into the concrete before polishing. For the floor to reflect differently, you can use several steps of concrete polishing and control the reflectivity you need.
Polished concrete is mostly found in commercial buildings as it is easy to maintain. The polishing process is done by heavy-duty polishing machines furnished with finer grits of diamond segments that soften the surface to the desired results.
Concrete Polishing Process
The polishing process starts by using coarse grit bonded in the metallic matrix to remove minor pits, stains, blemishes and light coatings on the surface. This can be termed as preparing the floor for final smoothing.
The concrete surface will determine the grinding process, this means it can be 3-4 steps of polishing and grinding. The next phase is grinding of the surface by the use of diamond abrasive rooted in a resin matrix. The lapping process is introduced. This is the use of ever-finer grit known as a polishing disk to produce a finer sheen.
To arrive at an extreme finer sheen or high gloss finish, you can increase the grit finer to 1500 or even more. The polisher should be able to know when to change to the next finer grit by having a close eye on the surface and the quantity of waste material being removed.
When the polish process is taking place, an internal sealer is applied which sinks into the concrete and becomes unnoticed. The sealer protects and densifies the concrete inside out and gives no room for adding a topical coat.
Various contractors add a commercial polishing compound on the surface during the last polishing step. Concrete polishing can be done using wet or dry methods. Dry polishing is mostly preferred as it tends to be faster and environmentally friendly.
In wet polishing, water is used as a lubricant to cool the diamonds, it also gets rid of dust and broadens the life span of abrasives used.
The wet polishing process creates a lot of slurries that need to be cleaned. On the other hand, in the dry polishing process, the polisher is connected to a dust containment system that vacuums all the mess.
Step-by-step Polishing Process
- Eliminate existing coatings, in case there are thick coatings use 16 or 20 grit abrasive
- Seal all the visible cracks and joints with a semi-rigid filler.
- Grind with 30- or 40- grit then 80-grit lastly 150- grit metal-bonded diamond
- Introduce a chemical hardener that will densify the concrete
- Start polishing with 100- or 200- grit resin-bond Diamond
- Polish with 400- grit followed by 800- grit resin-bond diamond
- To wrap it up, finish with a grit resin bond diamond of approximately 1500 or 3000
Once all the steps have been followed, you are advised to apply a stain shield. This is beneficial for it helps safeguard the polished surface. This in return makes maintenance easy.
The concrete polishing process is not an easy project. It requires heavy machinery with unique diamond tooling equipment.
Get yourself some qualified persons for the project. This is because they are well placed to understand the concrete polishing process and know what it takes to achieve a satisfactory result.
Safety precautions should be taken during and after the polishing process.