TEKNODUR COMBI 800-500

Remove from the surfaces any contaminants that might be detrimental to surface preparation and application. Remove also water-soluble salts by using appropriate methods. The surfaces are prepared according to the different materials as follows: STEEL SURFACES: Remove mill scale and rust by blast cleaning to preparation grade Sa 2½ (standard ISO 8501-1). Roughening the surface of thin-plate improves the adhesion of the paint to the substrate. ZINC SURFACES: Hot-dip-galvanized steel structures that are exposed to atmospheric corrosion can be painted if the surfaces are sweep blast-cleaned (SaS) till matt all over. Suitable cleaning agents are, e.g. aluminium oxide and natural sand. It is not recommended according to standard ISO 12944-5 to paint hot-dip-galvanized objects that are subjected to immersion strain. Painting of hot-dip-galvanized objects that are subjected to immersion strain must be discussed separately with Teknos. It is recommended that new zinc-coated thin-plate structures are treated with sweep blast-cleaning (SaS). Surfaces that have been weathered to matt can be treated also with RENSA STEEL washing agent. OLD PAINTED SURFACES SUITABLE FOR OVERCOATING: Any impurities that might be detrimental to the application of paint (e.g. grease and salts) are removed. The surfaces must be dry and clean. Old, painted surfaces that have exceeded the maximum overcoating time are to be roughened as well. Damaged parts are prepared in accordance with the requirements of the substrate and the maintenance coating. The place and time of the preparation are to be chosen so that the prepared surface will not get dirty or damp before the subsequent treatment. Additional instructive information for surface preparation can be found in standards EN ISO 12944-4 and ISO 8501-2.

Take into consideration the pot life of the mixture when estimating the amount to be mixed at a time. Before application the base and hardener are mixed in right proportion. Stir thoroughly down to the bottom of the vessel. Inadequate stirring or incorrect mixing ratio results in imperfect curing and impaired film properties. When needed, thin the paint with TEKNOSOLV 9521 or TEKNOSOLV 433. Apply by airless spray, brush, roller, and after diluting – conventional spray. Suitable airless nozzle size 0.011 - 0.015". Before use clean the spray gun and mixing vessels with a thinner TEKNOSOLV 9521 or TEKNOSOLV 433. Do not use universal thinners, since they may contain alcohol which will react with the hardener. When preparing painting specification, depending on subject and type of construction, different dry film thickness than recommended can be assumed. If is required to obtain a coating with lower thickness, it is recommended to dilute the paint, adding the recommended thinner in the amount of 5-10%. The minimum recommended dry film thickness is 50 µm. Different dry film thickness than recommended causes change in theoretical spreading rate, wet film thickness, weight of dry film thickness, drying time, overcoating time and ready for handling time.

The surface to be treated must be dry and the relative air humidity below 80%. Minimum surface temperature -5°C (surface frost- and ice-free) and at least 3°C higher than dew point during the application and drying period.

The storage stability is shown on the label. Store indoors in a cool and dry place and in a tightly closed can. The hardener reacts with air humidity and therefore the can is to be kept carefully closed. Use opened hardener within two weeks.