HOW TO grind & polish concrete to a gloss finish

The following notes described the typical processes carried out to achieve a high gloss finish on a suitable surface. Every concrete floor is different and the process may have to be varied depending on site conditions.

When changing from the metal bond diamonds to the resin hybrid based diamonds it can be advantageous to include an additional stage of the resin hybrid at 100 grit.

Preparation of the surface: Remove all dust and dirt with a floor cleaning machine and vacuum. Identify all defects: On the clean, dry surface identify any defects such as holes, chips, cracks, etc..

The polishing process:

  1. Perform the initial grind using metal bond diamond tools, 30/40 grit. This will expose the surface aggregate. If the surface layer is extra thick then it is recommended to use 16/25 grit tools before the 30/40 grit diamonds.
    • Use grinding/polishing machines at an average speed, making 3-4 passes over the area depending on  the surface condition. Each pass to be at 90 deg. to the previous
    • Then clean the floor with a cleaning machine after wet grinding or with a vacuum cleaner after dry grinding.
  2. Repair any defects (holes, chips, cracks, etc.) with suitable filler eg. Bostik 6000, Bostik Combi, Bostik Fin, or similar
    • Application instructions for the Bostik 6000, Bostik Combi, Bostik Fin are indicated in the relevant technical specifications.
  3. Continue grinding with metal bond diamond tools, 60 grit to remove swirl marks and scratches evident after the initial grinding.
    • Use grinding/polishing machines at a moderate speed, making 2-3 passes over the area. Each pass to be at 90 deg. to the previous.
    • Then clean the floor with a cleaning machine after wet grinding or with a vacuum cleaner after dry grinding.
  4. Continue grinding with metal bond diamond tools, 120 grit.
    • Use grinding/polishing machines at a moderate speed, making 2-3 passes over the area depending on the surface condition. Each pass to be at 90 deg. To the previous.
    • Then clean the floor with a cleaning machine after wet grinding or with a vacuum cleaner after dry grinding.
  5. Polishing the surface with a polymer bond diamond tools, 200 grit.
    • Use grinding/polishing machines at a moderate speed, making 2-3 passes over the area. Each pass to be at 90 deg. to the previous.
    • Then clean the floor with a cleaning machine after wet grinding or with a vacuum cleaner after dry grinding.
  6. Application of colorant onto the clean and dry surface (if colour is needed).
    • Procedure for applying colours is described in the relevant application instructions.
  7. Removal of excess colorant and application of impregnating hardener/densifier NANO-­SILICA or NANO-­ LITHIUM on dried (coloured) surface.
    • Procedures for applying NANO-­SILICA or NANO-­ LITHIUM are described in the relevant instructions.
    • When completely dry (not earlier than 2 hours for NANO-­ LITHIUM, AND 12 HOURS FOR THE NANO-­SILICA) it is necessary to again clean the floor with a cleaning machine or industrial vacuum cleaner.
  8. Surface processing with polymer bond diamond tools 400 grit.
    • Use grinding/polishing machines at a moderate speed, making 2-3 passes over the area. Each pass to be at 90 deg. to the previous.
    • Then clean the floor with a cleaning machine after wet grinding pr with a vacuum cleaner after dry grinding.
  9. Polishing the surface with polymer bond diamond tools 800 grit.
    • Use grinding/polishing machines at a fast speed, making 2-3 passes over the area. Each pass to be at 90 deg. to the previous.
    • Then clean the floor with a cleaning machine after wet grinding or with a vacuum cleaner after dry grinding.
  10. Continue polishing the surface with polymer bond diamond tools 1500 grit
    • Use grinding/polishing machines at a fast speed, making 2-3 passes over the area. Each pass to be at 90 deg. to the previous.
    • Then clean the floor with a cleaning machine after wet grinding or with a vacuum cleaner after dry grinding.
  11. Application of impregnating hybrid sealer NANO-­LITHIUM-­PLUS in a thin coat onto a dry, clean surface.
  12. Final polishing of the surface
    • Polishing is performed not earlier than 12 hours after application of the NANO-­LITHIUM-­PLUS. Additional weights may have to be added to the handle of the grinding machine to lighten the weight on the grinding head. Use felt or other pads similar to horsehair that are light coloured.
    • The final polish is carried out at maximum speed.

The above is applicable for concrete slabs aged over 28 days

This document presents updated information, but as we are unable to monitor the use of the material and the compliance process, we are not liable for any loss or damage caused whether direct or consequential. Prior to commencing we strongly recommend the installation of a test area for the detection of possible nuances and characteristics of a particular floor, as well as to agree the final result with the client.