Understanding & Using Diamond Tooling for Concrete Surface Preparation

From industrial facilities and manufacturing hubs to residential buildings and high-end corporate headquarters all over the world, floors made from concrete, especially polished concrete, are becoming the preferred choice for contractors and their customers. In addition to reducing maintenance costs, concrete floors are durable, long lasting, environmentally sound for LEED projects, reflect light beautifully and can give the appearance of unique stonework.

Before a floor can be transformed however, the hard work of preparing an old floor for a new application must be taken care of. Not only to clean and sanitize, but to remove all built-up residues or coatings, which, if left on the surface, will impede any successful concrete polishing job. Depending upon the type of residue, the hardness of the concrete, the desired finish and the square footage of the area, grinding removes almost any coating, epoxy, glue or mastic. Between the actual grinding machine and the concrete is the diamond tooling, the real workhorse of any equipment package. Understanding how to determine the appropriate type of diamond tooling relative to the substrate you are working on, as well as the desired end result, is crucial.

Anatomy of Diamond Tooling

Definition: Diamond tooling cuts or polishes a concrete surface using one of the hardest materials on Earth: diamond grains, a distinct advantage compared to tools that use common abrasives such as corundum and silicon carbide.

Bond: In order for a grinder to use diamonds to cut, small chips of diamonds are suspended in a bond made from metal, resin, carbides, hybrid or mixed-resin (a blend of both resin and metal bonds) or polycrystalline PCD.

  • Metal-bonded diamonds are ideal for removing brittle adhesives
  • Carbide-bonded diamonds are ideal for removing tacky adhesives, leaving a smooth finish and no damage to concrete
  • PCD-bonded diamonds are ideal for removing epoxy coatings, adhesives, leveling compounds or membranes and quite popular because they are so aggressive

To achieve the greatest productivity on hard concrete, a soft-bonded diamond needs to be used; conversely, a hard-bonded diamond needs to be used on soft concrete.

Segment: Segment refers to the raised part of the tool that holds the bond. More segments on the mounting plate means less head pressure, whereas a single segment withstands all of the head pressure.

Grit: Diamond tooling is available in various grits, indicating the size of the diamonds within the bond. The lower the number of grit, the larger the size of the diamond. The higher the number, the smaller or finer the diamond. Most concrete grinding jobs require a combination of diamond grits to achieve a desired end finish.

Concrete Hardness

Knowing whether the substrate you are working on is soft, medium or hard concrete determines the correct diamond bond to use, which dramatically increases productivity. You can determine concrete hardness by conducting a Mohs Hardness Test, which ranks the hardness of all minerals on a scale of 1 to 10 from softest to hardest. Concrete falls between 4 and 8 on the Mohs scale.

Surface Prep Selections

Diamabrush Mastic Removal Tool

  • Removes mastic, carpet or tile adhesive, thin-set and thin mil coatings like urethane or paint
  • Uses rigid, exposed diamond coated blades to grind stubborn coatings from concrete, creating a level floor with normal use
  • Retains sharp cutting points over the life of the tool
  • Designed to fit a wide variety rotary flooring machines
  • Low profile design enables tool to travel over gaps in the concrete
  • Simply apply water to eliminate dust and to flush debris away
  • Money saving replaceable blades

Husqvarna Pirhana PCDs

  • Rids concrete of hard-to-remove coatings, adhesives and screeds
  • Specially formulated grade of Pirahna PCD diamond scraper inserts ensure maximum wear and productivity
  • For use on the PG machinery range in conjunction with the Redi Lock system
  • Single or double quarter-round PCD with protective diamond strip
  • Tools can be re-tipped once worn out

HTC Metal-Bond T-Rex Series

  • Removes coatings as opposed to grinding them, including thick coatings such as paint, epoxy, varnish, acrylic, glue and screed residue
  • Finer scratch pattern
  • Leaves a good profile for laying down a new floor covering
  • T-Rex EZchange Gold allows the user to choose the correct grinding pressure needed

Trends In Diamond Tooling

One of the hottest trends in diamond tooling today is the use of transitional diamonds or hybrid diamond tooling, which combines the deep cutting and grinding action of metal tooling with the softer polishing action of resin tooling, making the progression from grinding to polishing easier and faster. Modern contractors are also testing the use of diamond-impregnated pads, which are easier to use and tend to last longer than traditional diamond tooling.


[INFOGRAPHIC] How to Polish Concrete with Husqvarna

After several requests for a step-by-step guide to polishing concrete with Husqvarna tooling, here it is. This 9 step concrete polishing process gives a general outline for which grits to use in each stage, the exact tool to use in each and best practices. Keep in mind however, that this is by no-means translatable to every concrete slab, it may vary, but it gives a solid starting point.

Also, in order to understand the speed requirements, it’s important to be familiar with Husqvarna’s Dual Drive Technology™ and specifically the functionality of Husqvarna floor grinder control panels, which have 2 speed controls (potentiometers). For an overview of Dual Drive Technology™, check out this blog post.

How to Polish with Husqvarna

For a complete catalog of Husqvarna grinders and tooling, visit our website. Please contact us with any questions you may have. And if you would like a customized infographic for you and your crew, please contact us and we will make it happen!

The HTC Ravager’s Performance As Told by 2 Concrete Contractors

The HTC Ravager is a relatively new grinding tool with the ability to remove thick coatings and expose large aggregate. Two of our customers have recently used the Ravager for small demos, one removing a coating and the other exposing aggregate. Read on for the results.

1. Coatings Removal: The first is Scioto, who removed 10-12 millimeters of urethane epoxy coating in one pass with the Ravager. They were pleased with the outcome; you can see the Ravager in action in the images and video below.

2. Exposing Aggregate: The second demo was by Applied Flooring, who did a 10′ x 10′ patch in their shop on an already polished floor. The goal was to expose large aggregate with an HTC 800 Classic and the Ravager. The Applied crew tested at various speeds (1, 5 and 10), and determined that the higher the speed, the more quickly this tool tore up the concrete. With that said, the Ravager effectively took the slab to the desired aggregate after two passes. One thing to note for anyone wanting to use the Ravager on an 800 Classic though, is that the tool makes the machine stand up tall, so you may need to adjust your shroud so as not to have a gap that allows dust and dirt to fly up. See images from this demo below.

We’re looking forward to seeing how well this tool performs with other jobs. The only question now is how long a Ravager tool lasts…time will tell. The Ravager is relatively straight forward and has many applications, so there is a lot of potential. For more information on the HTC Ravager, please refer to the product spec sheet. And if you’ve used the Ravager and would like to share your experience, please comment in the section below.