Surface Preparation Best Practices for CTS Rapid Set Products

shot blastingRegardless of trade, preparation is often the single-most important step to ensure a professional installation. This is especially true when contractors are looking to install cement toppings. CTS Rapid Set concrete is specifically designed to harden and set within minutes of mixing, which can drastically increase contractor productivity. By setting rapidly, contractors can avoid the typical 30 day cure time many other concrete mixes require. Most CTS products allow contractors to return the next day to begin polishing or coating the placed slab. Preparation for CTS Rapid Set Products can be broken down into two steps: Surface Preparation and Priming the Surface.

Prepping the Substrate: The substrate should be clean, have an absorptive surface, be free of oil, curing compound, sealers, hardeners, or any other material that would inhibit adhesion. The surface should be mechanically prepped, with the preferred method being shot blasting or grinding. The surface of the concrete can be measured using the ICRI Concrete Surface Profile (CSP) of between 3-5. Shot Blasting is typically the easiest method for achieving this profile. See this chart below, which overviews surface profiles.

CSP Inspection Guide

putting down TRU Epoxy PrimerPriming the Substrate: Once shot blasting and/or grinding is complete, the substrate should be primed to allow for maximum adhesion when the CTS Rapid Set is placed. CTS Rapid Set offers both an acrylic primer, as well as a 2-part epoxy primer. The acrylic primer is mixed 1:1 with water and applied to the floor using a soft bristle broom at between 400-600 sq. ft. per gallon. A second coat of acrylic primer might be necessary depending on porosity of the slab.

The second option for priming the surface, is CTS TXP 2-part epoxy primer. TXP offers superior bond strength, one coat application, can withstand interior and exterior applications, and allows for placement of Rapid Set products in as little as 12 hours. The surface is prepared the same way, achieving a CSP of between 3-5. The floor is then cleaned using an auto scrubber. The TXP is mixed at 2 parts A to 1 Part B (2:1) using a slow speed drill mixer. The material is poured onto the substrate and applied using a notched squeegee and back-rolled using a 3/8″ nap roller at around 12 mils thick (0.3mm). After the coating is placed and still tacky, clean, dry silica sand should be broadcast to rejection using mesh #20-#30 sand. Once dry, the excess sand can be removed from the floor.

Once preparation and priming is complete, the floor is now ready for placement of CTS Rapid Set products. Runyon Surface Prep Carries a wide range of CTS products, as well as the tools used to install the products. Click here for our “Build Fast, Build to Last with Rapid Set Cement Products” article, outlining the process and products needed for TRU self-leveling projects.


The Importance of Surface Prep for Decorative Epoxy Flooring

One of our customers in Florida, Artistic Surfaces, is a prime example for how important it is properly prep your concrete before putting down a coating – whether it be an epoxy, overlay, etc. Below are four different epoxy jobs that their crew completed recently, courtesy of Sam Godbey, the Director of Operations at Artistic. The pictures don’t do them complete justice, but it is very evident surface preparation played a major role, and we were happy to have a part in that.

Charcoal Metallic Floor

This 3,600 square foot charcoal floor is owned by a high profile client. It’s a private residence, used to store the owner’s cars, sports memorabilia, and other appropriately coined “toys”.

Artistic prepped the surface with an HTC 800, Ermator T8600 and 25 grit HTC diamonds. This is a grey epoxy with a combo of Sterling, Onyx and Quick Silver metallic pigments.

Harley Quinn-esque Floor

This blue and pink metallic floor looks like cotton candy. It is located in a residential dressing room. Artistic partnered with Coastal Construction for this job.

They prepped the surface with an HTC 500 and 25 grit HTC diamonds. It’s an epoxy with black pigment base and metallic pigment colors Surfs Up and Merlot.

Black & Aluminum Striped Bar

This black and aluminum striped floor is located in a 5,500 square foot bar called the Escape Lounge. The epoxy was poured with a black base and then the aisles were taped out in a curved design and colored with Aluminum metallic.

An HTC 800 and 25 grit diamonds were used to prep the surface. Artistic also used CTS Rapid Set TRU self-leveling overlay in the back of the bar. The black portion of the epoxy floor was pigmented with Jet Black metallic and the stripes were pigmented with Aluminum metallic.

Intricately Designed Office Floor

Artistic recently re-did their 1,300 square foot office floor. They cut off the old white overlay and transitioned it to an epoxy metallic floor. They kept the same detailed saw-cut design work.

To prep the surface, Artistic used a 60 grit screen and floor buffer. This epoxy floor required a myriad of metallic pigment colors for all the intricate designs: Copper, Butterscotch, Merlot, Mother-of-Pearl, Surfs Up, Rose, Maui and Jet Black.

After putting down the metallics, they used a regular blade and v-blade to re-cut the saw-cut designs. Then they filled the cuts with black grout. And finally, they re-sanded the floor and put down 2 clear coats of epoxy.

About Artistic Surfaces

Artistic Surfaces was founded in 1989 by Harvey Namm after 25 years’ experience in flooring. The Company soon became an award winning flooring contractor in the Florida market installing flooring in stores like; Macy’s, Bloomingdales, Burdines, and Saks 5th Avenue. Luxury hotels, Art Galleries, Airport Terminals, Performing Arts Centers, Sporting Arenas and other venues were added as the years passed.

In the winter of 2009, Artistic Surfaces launched a new division for decorative concrete. This new division will capitalize on the emerging demand for interior and exterior decorative concrete flooring. This new division marked the company’s entry as the area’s most experienced design applicators for decorative concrete concepts.

*All photos and information courtesy of Sam Godbey – Director of Operations at Artistic Surfaces. Reach him at

Surface Profile Inspection Guide from SP1 to SP10

A surface profile of concrete or asphalt is a number associated with the material’s desired roughness or texture and its general appearance. It helps in determining if the surface is fit for a specific purpose. Roughness can be an indicator for:

  • Wear-ability
  • Friction coefficients
  • Performance in terms of cracks or corrosion
  • Adhesive properties

Our Surface Profile Inspection Guide helps in determining the desired surface profile of your concrete or asphalt and indicates the proper diamond tooling and machinery required for achieving it during the preparation process.

Surface Profiles (SP1-SP10)

The lower the surface profile (SP) number (SP1), the flatter the surface. An SP10 rating is an extremely rough surface. An accepted definition of surface profile is “the average distance from the peaks to the valleys of the surface, as seen through a cross-section of the prepared substrate.” The range of variation with your specific concrete slab, substrate or asphalt depends on its strength, composition, aggregate and finish. The final surface must allow for the secure mechanical bond of any sealer, coating or marking material, so make sure the surface is free of any dirt, oil, films, paint, coatings, cure, sealer and any other material before creating your desired surface profile.

Runyon Surface Prep carries a full line of HTC, Husqvarna, and CPS grinders, Edco scarifiers and scabblers, National floor scrapers, diamond tooling, carbides, scrapers and shot blasters for use in surface preparation.

What Grinders, Scarifiers, Shot Blasters & Scabblers Can Do For You

Grinders, scarifiers, shot blasters and scabblers – these tools help contractors with the preparation of concrete surfaces. Whether it’s a repair job or decorative work, each of these machines have specific strengths for performing a number of jobs effectively. This article gives an overview of their capabilities, coverage rates, power options and benefits.


Grinders use cutting discs that rotate (rather than impact) to remove material at a depth of about 1/8 inch. They can be powered by electric, gasoline and propane and are versatile enough to be used in wet or dry conditions. Grinders use multiple types of tooling, pads or discs to perform a variety of tasks, made from silicon-carbide-impregnated grinding stones, tungsten-carbide inserts or diamond-segmented grinding tools (attachments for removing thicker coatings and mastics are also available). Grinders typically leave behind a smoother profile than scarifying or shotblasting because they polish hard, dense concrete rather than abrading the surface.

Grinders are available as walk-behind models good for floor and slab surfaces that range in size from single-, dual- and four-disc machines ideal for smaller jobs, to heavy-duty planetary machines ideal for high-production grinding of large slabs. Single-disc grinders have a working width of 10 to 12 inches, whereas dual-disc units cover 20 or more inches in one pass using counter-rotating discs to provide balanced torque so the grinder won’t pull from side to side. Planetary units range in coverage of 11 to 36 inches, with individual speed and direction control of the planetary head/s and satellite discs, optimizing any grinding application.

Disc rotation speeds range from about 250 to over 3,000 rpm, with floating heads that follow the contour of the floor, adjustable rear wheels that keep grinding discs level and vacuum ports which allow for dust-free, dry grinding.

Grinders are also available as hand-held models, good for working in tight areas where larger units can’t maneuver, such as in corners and close to walls. Grinding diameters for hand grinders range from 5 to 12 inches and can also be used to remove bumps, form marks, and graffiti from vertical surfaces or to grind concrete countertops.

Grinders come with a selection of grinding accessories and can be hooked up to an industrial vacuum for dust control. Not to mention, they are very adaptable for decorative work, as well as surface prep – profiling floors before application of thin coatings or paints because they won’t create ridges in the surface, as can scarifiers. Grinders are most effective at removing thin coatings and paints or for cleaning and lightly abrading floor surfaces. They also break up deposits of grease, dirt and industrial contaminants, level uneven joints or high spots and polish concrete surfaces with finer-grit abrasives.


Scarifiers, also refered to as surface planers or milling machines, remove concrete faster and more aggressively than grinders. Scarifiers can be powered by electric, gasoline and propane. They use the pummeling action of multi-tipped, interchangeable cutting wheels called flails that rotate at high speeds to chip away at the concrete surface. Cutters are made of tungsten carbide or hardened steel. Tungsten carbide cutters are more aggressive and longer lasting, making them practical for jobs requiring high production rates or scarifying of high-psi concrete, whereas steel cutters are less expensive and have a shorter life. Either type of cutter is available in different diameters, widths, number of cutting teeth and grades. Tip styles include blunt or flat for aggressive removal, sharp for gentler scarifying action or angled for scraping.

Scarifiers are available as small hand-held units with 2- to 3-inch cutting widths. They are also available as manual push or self-propelled walk-behind machines with working paths of 4 to 16 inches. Production rates range from 350 to 1,500 square feet per hour. Cutting depths are adjustable on most machines, with some models achieving up to 1/4 inch of material removal in one pass. Some models have self-leveling scarifying heads that automatically adjust to contours in the floor.

Vacuum attachments collect dust and debris. In addition, scarifiers have cutting wheels mounted to shafts of a removable drum; quick-change drums allow for easy switch or replacement. They leave behind a rough finish and may create ridges in the concrete. However, they can remove heavy floor tile mastics, rubbery elastomeric and epoxy materials, as well as perform light or heavy milling.

Scarifiers can also groove walkways to make them slip resistant, remove trip hazards in sidewalks, level misaligned concrete joints and uneven surfaces and can achieve different finishes by adjusting the spacing and pattern of the cutter assemblies; the closer the cutters are spaced, the smoother the finish.

Shot Blasters

Shot blasters use a one-step preparation method for stripping, cleaning and profiling surfaces for coatings and overlays. Shot blasters produce a roughened texture that improves adhesion of decorative toppings, as well as leave surfaces dry and immediately ready for recoating or resurfacing. Shot blasters can be powered by electric, diesel and gasoline.

Shot blasters use high velocity centrifugal force of a wheel with paddle-type blades to propel steel shot at the surface, fracturing off the surface layer of the concrete as well as any dirt, coatings, paint or other contaminants. Shot blasters also use an enclosed blast chamber that separates dust and debris from the spent steel shot, and recovers the reusable abrasive for recirculation. Shot blasters remove materials at a depth determined by the size and concentration of the shot, the rate of machine travel, shot impact force and condition of the surface.

Shot blasters are available as manual or self-propelled walk-behind units, with blasting paths range from 4 to 32 inches. Removal rates range from about 200 to over 3,000 square feet per hour. Smaller steel shot provides better coverage and higher production rates and smaller models are good for working in tight areas, around equipment and obstructions, next to walls or residential garage floors and balconies for decorative coatings.

Shot blasters are used for surface preparation such as very light etching to more aggressive removal of surface mortar down to coarse aggregate. They provide a cost-effective way to remove dirt, grime and chemical contaminants from large areas and for prepping substrates for self-leveling or polymer overlays, epoxy toppings and most coatings. Shot blasters produce very little airborne dust or debris, good for work areas such as food preparation facilities or manufacturing plants.

Shot blasters are affected by the hardness of the concrete or existing coating with regard to production rate and the depth of material removal. However, you’ll need multiple passes to remove thick coatings, rubbery mastics or heavy elastomeric coatings and are less effective than a scarifier. Shot blasters can leave “cornrows” where successive passes overlap, which can stay visible under a clear surface coating.


Scabblers are designed to roughen concrete surfaces more effectively than a grinder or scarifier. They use compressed air to hammer piston-mounted tungsten carbide bits into the concrete surface, up to 1,200 hits per minute. Scabblers have tungsten carbide bits that can last about 50 hours, and can be powered by air, electric and gas. Scabblers require vacuum ports for dust-free operation, as well as an automatic in-line lubricator or oiler for low piston maintenance.

Scabblers remove up to a 1/4 inch of concrete in a single pass, depending on the strength of the concrete. Typically it takes several passes to achieve a desired depth, but scabblers remove up to 200 square feet per hour at Depth Per Pass of 3/16”. Scabblers scabble down high spots in concrete, create excellent surface texture for bonding overlays and level uneven joints.

Scabblers are also effective in creating wheelchair access ramps, repairing sidewalk trip hazards, creating slip resistant surfaces, removing delaminated, spalled or deteriorated concrete and breaking up ceramic tile.

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.

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.

2 Proven Surface Prep Tools for Removing Glue and Mastic

You’re about to refurbish a concrete floor. Once you determine the square footage of the work area and the condition of the existing floor, you decide on the type of floor finish you want to achieve, and a budget. Before you can apply any new overlay or polish, you must first prepare the existing surface, removing any glue or mastic residue left from old floor coverings.

Glue & Mastic Residue Removal

Based on your initial assessment, use the overview below to determine which of the two most effective surface preparation tools for removing glue and mastic residue will work best for your floor revitalization project.

EDCO 10″ Propane Turbo Concrete Grinder

  • Grinding cup wheel includes 10″ diamond disc, 2″ – 3″ Multi-Vacuum Port, Water Port and Leveling Kit
  • Achieves super smooth surface profile with a working depth of 1/8″ per pass
  • Works four times faster than other conventional Edco grinders
  • Rounded shroud allows grinding within 1/2″ of any vertical surface with better dust control
  • Effective in a wet or dry environment
  • Ideal for grinding rough concrete surfaces and removing coatings
  • Rigid head assembly ideal for grinding uneven expansion joints, high spots, joint curls and bridge decks
  • Optional flex head assembly ideal for preparing a smooth, flat floor to receive a new coating
  • More costly because of diamond technology

Swing Machine with Diamabrush Concrete Prep Plus Tool

  • Can be installed on existing floor maintenance equipment
  • Ideally suited for hard-to-remove coatings and thin layers of paint or epoxy
  • Flexible blades designed to always remain in contact with the floor regardless of imperfections
  • Uses a 25 or 100 diamond grit bonded to metallic backing and assembled to flexible steel spring blades
  • Designed as the first step of a complete concrete floor preparation system that includes six different polishing tools used to achieve the level of gloss the floor application requires

When you do need specific equipment, count on Runyon Surface Prep. We carry a full line of EDCO grinders, as well as the Diamabrush Concrete Prep Plus Tool, among other Diamabrush tools.