ABC's of Spray Painting
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ABC’s of Spray Painting $10.00 A-2928-A ABC’s of Spray Painting Forward Table of Contents About this book….. Forward …..…………………..….2 While this book examines the spray finishing operation and its This book has been updated equipment from many viewpoints, several times from “The ABC’s of 1. Introduction ………………..3 there is still much more to be Spray Equipment,” originally learned to become truly proficient published by The DeVilbiss Surface Preparation………...3 at spray finishing. Company in 1954. It focuses on equipment and techniques for Paint Preparation……………3 spray finishing. The best way to become proficient at spray finishing is to 2. Air Atomizing Spray just do it! Many trade technical The format of the original book Guns………………………....4 and community colleges offer was question-and-answer. We Spray Gun Types ……….….4 courses in spray finishing, a great have retained that format in this way to improve your skills. edition. Part Identification and Function……………….……..6 Many of the “tricks” of the This book is organized around the Operation ……………..……..9 professional spray finisher involve major components of an air spray Maintenance ……….………11 paints and coatings. The system… spray guns, material manufacturers of these materials containers, hose, air control Troubleshooting …………...13 routinely publish complete books equipment, compressors, spray on these subjects. These booths, respirators and a short publications are available in section on general cleanliness and 3. Material Containers…...…16 specialty paint stores and will other sources of information. A provide you with considerable thorough understanding of the detail. Many of these books also material in this book - plus a lot of 4. Hose and Connections …18 contain information on techniques actual spray painting practice - for surface preparation. should enable you to handle just about any spray painting situation. 5. Air Control Equipment.….20 Another important source of information, particularly on Although we have made an effort 6. Respirators …….…….……22 equipment use and selection is to make this book as detailed and your local spray finishing as complete as possible, be aware equipment distributor. No book that the equipment and product 7. Air Compressors…….……23 could ever completely cover a systems used to illustrate points specialist’s in-depth knowledge of are entirely based on DeVilbiss equipment, techniques, technology. DeVilbiss is the 8. Spray Booths ……….…….25 maintenance and troubleshooting. world’s oldest and largest manufacturer of spray painting equipment, and has maintained Information is available from many this leadership since its founding resources on the subject of spray in 1888. finishing. It is our hope that this book will provide you with a start toward perfecting your finishing skills. A recent addition to resources available to the spray finisher is the World Wide Web. Many manufactures are represented and question and answer forums are available. Please visit our websites . at www.devilbiss.com and www.binks.com. 2 1. Introduction Plastic parts may contain static you close, but for professional This book is about the selection, electricity from the molding results, use a viscosity cup. It is a use and maintenance of finishing process. This static attracts simple but very accurate way to equipment: spray guns, tanks, particles of dust and dirt. Eliminate measure the thickness of paint. cups, hoses, compressors, them by treating with “destatisiz- With the cup, you can thin or regulators, spray booths, ing” air using a special blow-off reduce the paint to the precise respirators, etc. It presumes that gun that imparts a neutral charge consistency required by the you are familiar with standard to the airflow. A chemical anti- manufacturer. surface preparation techniques static treatment is also available. that may be required before Always prepare paint in a clean, finishing actually begins. It also dust-free environment. Paint has a presumes a basic knowledge of remarkable ability to pick up dirt. Paint Preparation the many different types of paints Dirty paint will not only clog your and coatings available. Today’s finishes are extremely spray gun, but it will also ruin your complex chemical formulations. paint job. Get in the habit of Creating a perfect finish requires a They include both solvent and always pouring paint into the cup solid knowledge of surface waterborne types. Some may or tank through a paint strainer. preparation, finishes and spray require the addition of solvents to Paint is never as clean as it looks. painting equipment. The first two form the proper spraying viscosity. are extensively covered in many Others may simply require the other books. The manufacturers of addition of a second component at paints and coatings have gone to a prescribed ratio to obtain great length to publish information sprayable consistency. Many of on their new and existing them also have hardeners or other products. chemicals, added to them to But, even an extensive knowledge insure correct color match, gloss, of surface preparation techniques hardness, drying time or other and paint chemistry is not enough characteristics necessary to to assure a professional finish. produce a first class finish. Make The finish must be applied by a sure you are familiar with the spray gun, and all the variables of specific finish material data sheets its use must be mastered. accompanying each material. Do not mix materials from various The equipment necessary to apply manufacturers. Read and follow the finish – the spray gun, tank, directions carefully. cup, regulator, hoses, compressor, etc. – must all be All finish materials must also be matched to the job as well as to supplied with a Material Safety each other. That equipment must Data Sheet (MSDS). This data be used and maintained properly, provides information on proper with an appreciation of how and handling and disposal of why it works the way it does. materials. Many states require that MSDS be kept on file by the user. The moment of truth for any finish happens when the trigger is The first step is knowing the type pulled. This book focuses on that and color of paint the project moment. requires. With this determined, follow the manufacturer’s instruction for preparing it exactly. Surface Preparation If you have any doubts about how to proceed, don’t guess! Contact The surface to be finished should your paint supplier for help. be well cleaned before painting. If Improperly prepared paint will the paint manufacturer’s never produce a good finish! instructions call for it, the surface should be chemically treated. Use The chief characteristic that a blow-off gun and tack rag to determines the sprayablility of remove all dust and dirt. No paint and how much film may be amount of primer or paint will applied is its viscosity … or cover up a badly prepared consistency. Following the paint surface. manufacturer’s instructions will get 3 3 2. Air Atomizing Spray Guns Figure 4 shows a material con- Suction feed is easily identified by Introduction tainer some distance away from the fluid tip extending slightly be- The spray gun is the key its pressure feed gun. yond the face of the air cap, see component in a finishing system. It figure 2. The type of material feed system is a precision engineered and is also a way of classifying guns: manufactured instrument. Each type and size is specifically Suction Feed... draws material to designed to perform a certain, the gun by suction as in Figure 1. defined range of tasks. Gravity Feed... the material travels As in most other areas of finishing down, carried by its own weight work, having the right tool for the and gravity as in Figure 3. job goes a long way toward get- Pressure Feed... the material is ting professional results. fed by positive pressure as in Figure 2 - Suction Feed Air Cap This chapter will help you know Figure 4. which is the proper gun by review- Suction feed guns are suited to Guns may also be classified as ing the Conventional Air and High many color changes and to small either external or internal mix Volume/Low Pressure spray gun amounts of material, such as in depending upon the type of air designs commonly used in finish- automotive panel/bumper repairs cap. ing - suction feed, gravity feed and and "completes," touchup, or pressure feed. It will also review lower production operations. the different types of guns and 3. What is a suction feed gun? components within each design. A spray gun design in which a A thorough understanding of the 4. What is a gravity feed gun? stream of compressed air creates differences between systems will a vacuum at the air cap, providing This design uses gravity to flow allow you to select the right gun, a siphoning action. Atmospheric the material from the cup, which is to use it properly to produce a pressure on the material in the mounted above the gun, into the high quality finish and to con- suction cup forces it up the suction gun for spraying. No fluid pickup tribute toward a profitable finishing tube, into the gun and out the fluid tube is used, since the fluid outlet operation. tip, where it is atomized by the air is at the bottom of the cup. cap. The vent holes in the cup lid This cup has a vent hole at the top must be open. This type gun is SPRAY GUN TYPES of the cup that must remain open. usually limited to a one-quart, or It is limited to 34 ounce capacities 1. What is an air spray gun? smaller, capacity container and due to weight and balance. low to medium viscosity materials. An air spray gun is a tool which Gravity feed guns are ideal for uses compressed air to atomize small applications such as paint, or other sprayable material, automotive panel/bumper repairs and to apply it to a surface.