Grinding concrete

“Mega Hire supplies equipment with the best quality blades and consumables to maximise the performance of your hired equipment”

Mega Hire includes the cost of 1mm of diamond disc wear per day, or 5mm per week, in the hire price for concrete floor grinders. The discs are measured with a vernier scale before and after use to calculate the disc wear.

We are asked frequently about how much you can cut / grind with 1mm of usage. The correct, but unhelpful answer, is “how long is a piece of string?”. Diamond disc usage is dependent on a large range of variables such as the age of the concrete, the aggregate used, the concrete strength (25MPA, or 35MPA), even how the concrete was finished when it was poured, but also how the equipment is used. Unlike some hire companies, Mega Hire uses the highest quality consumables in our equipment, so you can be guaranteed you get the most out of your hire.

The hand-held Hilti DG 1500 grinder includes 1mm of wear on a daily rate and 5mm of diamond wear on a weekly rate. Basic information on the handheld grinder can be found at the Hilti website. 

Selecting the correct diamond disc

We rely heavily on Floorex Products for information and technical advice on all things related to concrete preparation equipment and consumables. They are known to be the market leading supplier of all concrete treatment machines and diamond consumables. They have excellent resources online to help you with your concrete project. As a starting point, see the Floorex How To page. There is also further information at Floorex Concrete Preparation Guide page, or more in-depth training guides at the Floorex Premium Training Academy. Floorex' technical staff are always available to answer questions and provide advice, you can contact their store at Wacol on 07 3608 5100

A range of discs are available with varying grit densities, bond strengths and numbers of segments to suit different applications. Selecting the correct disc depends on the task and required finish.

Typically, it is best to start with a 30grit White disc (hard bond) and assess the wear rates and concrete grind as you progress. If progress is limited, this may be due to the hardness of the concrete, so switch to a 30grit Black disc (soft bond) which will respond better to hard concrete. For removing coatings such as tile glue or epoxy coatings, typically discs with less segments work better as they have larger open areas to disperse the material that is being removed (orange disc with three segments is recommended).

Once the surface has been ground down to show the aggregate with the course discs (black or white), the next step is to finely grind the concrete with an 80grit and then 150grit for a perfectly smooth finish. Following this, resin pads can be used for the final polishing step. Refer to our concrete polishing guide for further information.

Feel free to inquire for advice on selecting the best set up for your application.

Wear is charged as follows (per mm):

Concrete Floor Grinder 250mm - $55 (inc GST)

Concrete Floor Grinder 480mm - $35 (inc GST) per disc (the machine uses three discs at once)

Following are some useful info-videos for grinding concrete