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501-32-3 Paint Preparation and Application 501-32-3 DESCRIPTION AND OPERATION (Continued) at any time. Isocyanates react with water, which refinishing is to be the in-field equivalent of the factory destroys their effectiveness. Gas is involved when the finish. Two part urethane finishes are recommended. isocyanate reacts with water. If a closed container Two Pack Paints - Surface Preparation shows signs of internal pressure, cover it completely with a cloth and remove the lid slowly to prevent Essential Requirements and General Hints splashing or violent expulsion of the lid. If using only 1. Wash door jambs, engine compartment, etc with portion of the hardener in a can, reseal and use the high pressure hose before sanding and priming. balance of the contents within 36 hours, as it will This will remove all dust and dirt likely to deteriorate on exposure to air. Store in a cool, dry contaminate the top coat. place. 2. Wash surface thoroughly with a grease and wax Accidental spillages should be absorbed into dry sand solvent before sanding and application of primer. or earth, removed from the work area and covered Sanding will not remove wax and grease. Instead, with water for 24 hours. Treat empty hardener it spreads it from one panel to another, leading to containers in the same manner. Do not allow poor adhesion, and cratering if sealed in the materials of this type to enter drains. Dispose of primer. treated waste as directed by the relevant waste disposal authorities. 3. Strain lumpy primers and filler before adding hardener. Lumps will not catalyze and will remain Application soft. These soft areas will show after top coating. Isocyanate paint must only be applied in a spray 4. Wet sand primers and top coats containing booth fitted with an effective filtered exhaust system. isocyanates. Dust particles containing isocyanates The operator must wear the protective equipment can be hazardous to health. prescribed in these guidelines and comply with local 5. Use solvents sparingly over primers and fillers. It legislation applicable to the spray painting of motor can take up to two hours for cleaning solvents to vehicles. evaporate. If sealed in with the top coat it can Additionally, particular care must be paid to other cause “whirl” marks to appear in the paint film. people in the vicinity. The work area should be 6. Mask off vehicle openings, door jambs, engine isolated from other people during all activities compartments, wheel arches, etc. This will reduce associated with the mixing, handling and application the risk of dust and dirt blowing out during top of isocyanate paint until all vapour and spray mist, etc. coat spraying. has been effectively dissipated. 7. Never apply two pack primers over unsanded Whenever unlidding, mixing or the clean-up of liquid surfaces, especially existing finishes. Adhesion residues is taking place, the area in use must be well will be poor. The primer edge will not feather ventilated by an exhaust system sufficient to capture properly and will lift or swell when top coated. all vapour or spray mists generated and conduct them 8. Never use conventional etch primers under two away to a safe discharge point. Where the air flow pack primers. Two pack primers have good velocity in the work area is below 1 metre per second, adhesion to all bare metals but not to at least one hour should be allowed before the conventional etch primers. exhaust ventilation is switched off. 9. Never attempt to use two pack primers or fillers to Wet sanding is the preferred method. Sanding of seal down cracked or crazed surfaces or film isocyanate films should be carried out under the same thicknesses exceeding 250 microns. Unless conditions as apply to spraying, as the dust may stripped, this type of surface will continue to crack irritate operators susceptible to isocyanate contact. under any primer and will eventually pull open the First Aid new top coat. 10. Never use polyester spray fillers on wet or humid If affected by inhalation of vapour or spray mist, days. Polyester spray fillers are very moisture remove to fresh air. If breathing difficulty persists or absorbent and will blister easily. They should be occurs later, consult a doctor and have label dry sanded and primed as soon as possible after information available. application. In case of eye contact, flush immediately with plenty 11. Never use too coarse a paper on final sand of of water for 15 minutes; call a doctor. In case of skin primer before application of top coat. They have contact, remove contaminated clothing and wash skin low film build and will not fill coarse scratch thoroughly with soap and water. Immerse marks. contaminated clothing in water for 24 hours and do not re-use until it has been laundered. 12. Do not exceed these levels of coarseness. Factory Finish The vehicle is finished in either baked polyester solid colour or baked acrylic clear over base coat colour; all G456450 en |