Paste adhesives trowels

Independent of final adhesive viscosity, hand application, by spatula, palette knife or trowel, is often the favoured method. However, once mixed, low viscosity adhesives are frequently pumped to an applicator gun, which is often robotically controlled. Higher viscosity paste adhesives can make use of hand-held cartridge dispensers which not only mix the adhesive, as indicated above, but also can apply a bead or stripe of adhesive to the substrate, dependant on the design of the applicator head. 

Pastes and Mastics. Bulk adhesives such as pastes or mastics are the simplest and most reproducible adhesive to apply. They produce heavy coatings that fill voids, bridge gaps, or seal joints. They can be in the form of high-viscosity extrudable liquid or a trowelable mastic. 

These systems can be troweled on or extruded through a caulking gun. Little operator skill is required. Since the thixotropic nature of the paste prevents it from flowing excessively, application is usually clean, and not much waste is generated. With trowel application, the depth of notch and the spaces between them help regulate the amount of adhesive applied. Shallow, rounded, and closely spaced notches are often used with lower-viscosity adhesives to allow the lines of adhesive to flow together and form a continuous, unbroken film. 

S Mode of Application and Setting. Adhesives are often classified by their mode of application. Depending on viscosity, adhesives are sprayable, brushable, or trowelable. Heavy-bodied adhesive pastes and mastics are considered extrudable they are apphed by syringe, caulking gun, or pnenmatic pnmping equipment. 

Pastes, mastics Highly viscous single- or two-component materials that cure to a very hard or flexible joint depending on adhesive type. Does not run when applied. Shelf and pot life are often limited. Often applied via a trowel, knife, or gun-type dispenser one-component systems can be applied directly from a tube. Various types of roller coaters are also used. Metering-type dispensing equipment in the 2,500 range has been used to some extent. 

They are used both for professional tile setting and - owing to their simple processing properties - in the do it yourselF (DIY) market They have a broad adhesion spectrum, a long working time and form a flexible adhesive film. Mastics are generally water based and are supplied as a smooth trowelable paste for setting smaller sized tiles (<15 cm x 15 cm). 

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