Preparatory
Preparatory
Shotblasting
Shot blasting is a very clean way to produce a surface profile. This method is very simple, small steel shot is placed into a reservoir and is feed into a paddle wheel that is spinning at approx. 300mph. This is equivalent to a Tornado. The wheel then projects the shot on to the surface removing loose concrete and laitance. This opens up the concrete and gives it a heavy sand paper profile. It also will clean out cracks and joints. This profile can be very rough which is great for epoxy coatings. This profile is not as favorable for thin mil coatings that cannot cover the peaks and valleys of the concrete and will consume more product.
Though this product gives us a great profile for adhesion it does not remove some coatings very well. It does get into places that grinding system will not reach.
Grinding
Diamond grinding is becoming the preferred method of prepping in today’s flooring industry. With polishing taking a big chunk out of the commercial – industrial markets these machines have been improving and are being priced in reach. Diamond grinding is the rotation of one or more abrading stones or discs applied under pressure at right angles to the surface. This method may be used on horizontal surfaces to remove deposits or coatings and to reduce or smooth surface profile. The grinding diamonds is applied under pressure and moved across the surface until the desired effect is achieved. Diamond grinders can utilize both metal or resin bond diamonds that can be used either wet or dry for concrete grinding. Solid carbide scarifying cutters are used for thicker coatings. Grinders can also be used effectively to level uneven joints or high spots of 1/16 to 1/8 inch. Grinding provides contractors with a smoother finish than shot blasting, scarifiers or scabblers.
Scarifying
Scarifying is the rotary action of the cutters (toothed washers) impacting the surface at a right-angle ton fracture or pulverize the top surface of the concrete to exposer a clean, fresh surface. The cutters are assembled on tempered rods mounted at the perimeter of a drum that rotates at high speed. Scarification is used for the removal of concrete or coatings up to ¼” thick. It may also be used to profile concrete surfaces. Scarification can also cut deep grooves into the concrete to provide a non-slip surface.