Auto Technical Reference Library
Auto Refinishing
Auto Technical Reference Library |
Topic
Index |
Acid Rain – Acid rain is largely created when sulfur dioxide and nitrogen dioxide are discharged by factories and power plants. When acid rain falls on a vehicle, the moisture evaporates but the acid remains. Concentrated by sunlight, the sulfuric acid can become so strong that it will eat through or etch a car's finish.
Adhesion – The ability of the paint film to adhere to the surface beneath it.
Air Blowing – Using an air blow gun to blow dust and dirt off the vehicle and its parts. It has a trigger that can be pressed to release a strong stream or blast of air. A blow gun can also be used to dry panels after wet sanding and to also remove debris along trim pieces and other enclosed areas.
Basecoat – A highly pigmented color which requires a coating of clear for protection, durability and gloss. Basecoat is used in two-stage and three-stage paint procedures. Most basecoats dry in 5 minutes and can be sanded and recoated if imperfections appear.
Blending – The gradual shading of paint from one panel to adjacent areas to assure color consistency.
Blending Agent – Blending Agent is a ready-to-spray liquid utilized to melt the edge of topcoats to make invisible blend repairs where full panel refinishing is not desirable.
De-nib – To remove any surface imperfections or contaminants in the top coat. This can be accomplished by either wet or dry sanding and then followed by machine buffing.
Buffing – A technique used to machine polish an area to remove sanding marks or surface imperfections.
Car Cover – See Mask below
Clearcoat
Gloss – A translucent coating containing no pigment or only transparent pigments. Clearcoat is used in two-stage and three-stage paint procedures for durability, gloss and the proper protection of metallic and solid colors.
Matte – A translucent coating containing no pigment or only transparent pigments. Commonly utilized for underside panels but is now trending towards exterior finishes as well.
Ceramic/Cross link clear – Ceramic Clearcoat uses nanotechnology to migrate silicon particles to the outer surface of the coating, creating a very thin, hard, glass-like surface. It creates a scratch resistant surface which is at least three times better than that of any prior coatings, while maintaining excellent acid etch resistance.
Self-Healing Clear – Self-healing clearcoat actually repairs scratches upon heat activation such as the sun. This technology enables the clearcoat to reflow when it is exposed to warm temperatures in order to heal scratches arising from day-to-day use
Color Sanding – The sanding of a paint film to prepare for buffing or recoating.
Color Sand & Buff – Involves a thorough sanding and polishing of the entire surface to remove surface texture or contaminants to better match the OEM finish and texture.
Corrosion Protection – the process of applying corrosion-inhibiting chemicals, waxes or sealers to the underside and inside of the vehicle's body
Dry Sand – A term describing sanding completed with sandpaper, without using water. Dry sanding is for the adhesion of a top coat and also done to remove material quickly. It can also be utilized as a finishing operation prior to machine buffing.
Dust and Water Removal – Compressed air is typically utilized to remove dust and dirt off the vehicle and its parts. It can also be utilized to dry panels after wet sanding and remove debris along trim pieces and other enclosed areas.
Electrostatic Painting Process (E-Coat) – Manufactures utilize a negative and positive charge to precisely target the paint to the vehicle body. This eliminates waste and provides uniform coverage.
Epoxy Primer – A two-part water resistant primer that has the capabilities of filling and sealing. To initiate the chemical reaction between the primer and the catalyst, some epoxy primers need to stand a predetermined amount of time before it is applied. Epoxy primers are especially effective in weld joint areas and enclosed areas such as the box section of a frame rail.
Etch Primer – A one part primer which contains an acid for chemically treating metal for corrosion resistance. Etch primer also promotes adhesion for the primer filler which must be utilized with another priming product. This product is not designed for enclosed areas or to have body fillers applied. (add link for photo)
Feather, Block and Prime – The process of bringing a repaired panel to the level of a new undamaged panel for refinish processes.
Featheredge – A sanding process of tapering a broken paint edge to a smooth finish. Feather edging is sometimes completed by the body repair technician prior to entering the refinish department.
Flex Additive – A substance added to paint to improve its performance characteristics such as impact resistance and flexibility over plastic or flexible surfaces.
Guide Coat – A reference coat of a different color often applied to a primer filler. It is sanded off to visually determine if the panel is straight and free of imperfections. Aerosol spray and carbon based powders are just a couple of the products used as a guide coat.
Mask – Process of applying tape and paper to a vehicle to prevent paint from being applied where it is not wanted. To avoid overspray, the remainder of the vehicle is covered with a vehicle cover, plastic, paper or a liquid mask that is water-soluble.
Midcoat – The additional coat applied after the basecoat and before the clearcoat in a three-stage paint procedure. The midcoat is almost always a pearl color.
Mix Color – Mixing paint based on a paint formula with percentages of each ingredient that is needed to match an OEM color.
Mixing Coatings – Involves blending the paint with hardeners, activators, thinners, reducers and other additives to the correct thickness or viscosity. Today, paint manufacturers require that most mixing systems utilize scales to obtain the pre-determined weights and measures when mixing coatings. These measuring systems save a lot of time and material costs.
Paint Code – Numbers, letters or the two combined for mixing the right type and color paint. Paint Codes are listed on the body I.D. plate on the door, console lid, trunk, trunk lid or elsewhere on the body.
Paint Variants (chips or decks) – Paint manufactures will typically provide convenient samples of vehicle colors on cards or chips to easily identify the vehicle color. Repair facilities can also develop and maintain their own color library as well.
Primer – The name of the base coat or first adhesion-promoting coat applied to the surface to be painted, primer is designed to promote adhesion and corrosion resistance.
Primer Filler – A primer used to fill pitted or rough surfaces and later smoothed by sanding after primer has cured. A non-corrosion inhibiting primer/filler should not be used directly over bare metal structural or cosmetic parts.
Powder Coat – A type of coating that is applied as a free-flowing, dry powder which does not require a solvent to keep the binder and filler parts in a liquid suspension form. The coating is typically applied electrostatically via a spray application and is then cured with heat.
Rust-Proofing – The application of a PVC type of rubberized sprayable liquid that preserves and protects objects constructed of iron and/or steel which are subject to rust.
Scuff Pad – A synthetic pad utilized to clean and lightly scratch the vehicle surface so that new paint will stick. This procedure is usually performed when blending within and into a panel. Scuffing allows the clear to adhere to the existing finish. (A coarser scuff pad is sometimes used to scuff around a repair area before priming. This allows the primer to adhere to the existing finish.)
Sealer – An undercoat that enhances topcoat adhesion by isolating and sealing absorbent and relatively porous substrates. Sealer is often used over e-coat instead of spraying and sanding a primer or primer/filler.
Single-Stage Color – A one-step paint procedure of applying color, protection and durability in one application. No clear is used.
Spot Refinish – The process of isolating the refinish work to be completed within the damaged panel using a graduated spray application that will create a proper color match without impacting non damaged panels.
Spray-Out Panel (Let down panel) – This is a test to panel to assist with making a blend decision, the mixed vehicle color is sprayed onto a spray out panel and then compared to the vehicle for color match. The spray out panel contains different levels of color to provide coverage guides which are documented to assist with the color match. These spray out panels are vital when matching the vehicle color when color variants exist.
Solvent Wash – A solvent based cleaning material used to remove contamination from surfaces prior to refinishing. A rag dampened with cleaning solution is wiped across an area to be refinished, followed by a dry rag to assist in the evaporation process.
Solvents – Low-viscosity liquids used to dissolve the substances that form the paint film. The solvent (thinner or reducer) used to dilute paint must be adapted to the components of the solvents contained in the paint.
Spray Guns
Siphon Feed – Siphon style guns have reservoirs that hold as much as a quart of reduced sprayable liquid. The movement of the air inside the spray nozzle creates a siphon that pulls paint out of the reservoir via the siphon tube.
Gravity Feed – Gravity-feed guns mount the paint reservoir on top and utilize gravity to allow the paint to flow down into the air stream. These reservoirs typically can hold about a pint of reduced sprayable liquid
HVLP – This is similar to a conventional gravity feed spray gun using a compressor to supply the air, but the spray gun itself requires a lower pressure (LP) and a higher volume (HV) of air to aerosolize and propel the paint. The result is a higher proportion of paint reaching the target surface with reduced overspray and materials consumption.
Note: Special considerations are required when spraying any waterborne products as these require stainless steel spray gun technology to prevent the internal parts of the spray gun from corroding.
Stone/Chip Guard – There are multiple applications of stone and chip guards available. These can be paint applied, adhesive applied and solid metal or plastic type guards.
Tack Wipe – Wiping surfaces to be refinished with a tack cloth, which is sticky and used to remove dust and other fine particles.
Tinting – The mixing of a color, or the final adjustment of the color of a ready-mixed shade, to match the vehicle to be painted.
Two-Tone – Refers to a second application of a different color on the same panel.
Undercoating – Undercoating materials adhere to either bare or painted metal surfaces. Most come in pressurized cans for easy spray-on application or can be spray on commercial applications. Ingredients used in manufacturing include fiberglass, rubber, ceramics, silicone, asphalt, or petroleum. Each has different properties in terms of heat retention and resistance but all do offer protection against the elements and damage caused by moisture, debris and road salt as well as sound insulation.
Volatile Organic Compound (VOC) – Are organic chemicals that have a high vapo pressure at ordinary, room-temperature conditions. VOCs are typically found in solvents that make up a large percentage of automotive paint products. VOCs are regulated by law, especially indoors, where concentrations are the highest. Harmful VOCs are typically not acutely toxic, but instead have compounding long-term health effects. An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon.
Wash Primer – A pre-treatment for sheet metal that offers good adhesion and corrosion protection for the surface being painted. Wash primer components include phosphoric acid (for adhesion) and Zinc chromate (for corrosion resistance). Also called an etching primer.
Waterborne – The solvent in automotive coatings thins pigment solids for smooth and even application and then evaporates. Waterborne coatings contain water as the main solvent but also contain other solvents, such as glycol ethers, to improve application. These coatings are ideal primers because they have greater resistance to heat and abrasion and provide excellent adhesion. Waterborne primers and primer-surfacers have a volatile organic compound (VOC) content as low as 1.2 lbs/gal. Manufacturers and repair facilities are now utilizing this technology that is environmentally friendly and very high tech.
Wax and Grease Removal – Wax, grease, oil, tar and other surface contaminants reduce the adhesion of paint. Proper pretreatment of the surface to be painted requires a thorough degreasing.
Wet Sand – Using sandpaper that can be used with water for flushing away sanding debris that would otherwise clog fine grits. Wet sanding is for the adhesion of a top-coat. Occasionally coarse dry sanding is done first to remove major surface imperfections, followed by wet sanding for final smoothing.
Wet Sand and Buff – A finishing operation which consists of a back and forth scrubbing action with the sandpaper mounted on a rubber blocking tool. Block sanding is often used on flat surfaces helping level the surface, make it flat or to better match the existing factory texture (orange peel). Block sanding can be done wet or dry. Once the sanding is complete, the surface is then machine polished to restore the shine.
