Selecting and Applying Painting Materials Unit 29 Selecting and Applying Painting Materials

Paint What is the purpose of Paint? There are two types of paint: To improve: Appearance To preserve There are two types of paint: Oil-based Water-based (latex)

Paint What are the two types of paint finishes? Types of Finishes Enamel (shinny) Flat finish (dull) What is the correct temperature for painting? The correct temperature for painting is: 75 – 95 degrees Fahrenheit

Application Methods Brushes and Rollers Low cost Used for most home and farm projects Brushes are useful for small paint jobs and painting irregular areas Rollers are the best method for making, wide, flat and quick applications.

Spray Guns Application Methods Device that releases paint in the form of a fine spray Two types: air atomization: paint is split into tiny droplets using compressed air (pneumatic) airless: paint is pumped through hoses under high pressure; no air is used

Spray Guns (continued) Major parts gun body fluid control knob pattern control knob air valve paint needle valve packing nuts fluid nozzle air nozzle trigger

Aerosol Can’s Application Methods Pressurized paint in a disposable can. Cheap Easy to use Little clean-up

Preparing Wood and Metal for Painting Methods used to prepare wood and metal for painting are: Sandblasting Pressure Washer Wire Brush Sanding Chemical Solvents

Spray Painting Procedure Prepare the surface Choose an appropriate location Follow safety precautions Prepare the paint Adjust the spray gun Operate the spray gun Clean equipment

Safety Rules Mix paints and solvents in well-ventilated areas Spray paint outdoors or in special booths Never smoke or have any source of fire in the vicinity Wear a respirator or paint mask Only use ladders that are in good condition Avoid electrocution! Keep aluminum ladders away from all electrical wires

Safety Rules Mix paints and solvents in well-ventilated areas Spray paint outdoors or in special booths Never smoke or have any source of fire in the vicinity Wear a respirator or paint mask Only use ladders that are in good condition Avoid electrocution! Keep aluminum ladders away from all electrical wires

Operating a Spray Gun A gun stroke is made by moving the gun parallel to the work The closer the gun is to the work, the faster it must be moved to avoid sags and runs The farther the gun is away from the work, the drier the paint spray and the more spray dust is created

Important Terms Formulate: to put together according to a formula Chalking: formulated so that a tiny bit of the film washes off each time it rains Trim and shutter paint: formulated to stay bright without chalking Enamel: paint with a gloss or semigloss finish Gloss: shiny Semigloss: slight shine

Important Terms (continued) Flat finish: dull or without shine Water-base: contains a water vehicle Oil-base: contains an oil vehicle Latex: water-based paint Alkyd: oil-based paint Epoxy: synthetic material with special adhesive and wear-resistant qualities Interior: does not hold up to weather Exterior: withstands weather conditions

Important Terms (continued) Hiding power: ability to a create color and mask the presence of old colors Lead: metal that has a cumulative toxic effect and stays in the body once ingested Titanium dioxide: high-quality pigment Calcium, magnesium, silicon: low-quality pigments Asphalt: provides excellent black hiding power Undercoater: used to prepare surfaces for high-quality top coats

Important Terms (continued) Compatible: go together without undesirable reactions Drop cloth: material used to protect surroundings from paint droppings Fingering: dividing of bristles Loading the brush: removing excess paint to prevent dripping Paint roller: cylinder that turns on a handle Nap: the soft, woolly, threadlike surface of the roller cover

Important Terms (continued) Propellant: propels paint toward object being painted Regulator: keeps air pressure at a set level Extractor: removes moisture and oil from the compressed air Siphon system: has a small vent hole in the cap of the cup Pressure feed cup and pressure feed tank systems: operate with the paint under air pressure at all times

Important Terms (continued) Aerosol: high-pressure container with a valve and spray nozzle CFM: cubic feet per minute Viscosimeter: instrument used to measure the rate of flow of a liquid Viscosity: a liquid’s tendency to flow Roller cover: hollow, fabric-covered cylinder that slides onto the roller handle

Important Terms (continued) Sag: when a large area of paint shifts downward because it has been applied too thick Run: narrow stream of paint flowing downward due to excessive buildup Tacky: sticky