26 Paint Mixing and Reducing Chapter

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Objectives After studying this chapter, you will be able to: Know where to find a paint code on a vehicle. Understand how to use the paint code to obtain the paint part number. Understand the importance of thoroughly stirring tints. Explain how to mix a color. Know how to reduce paint by volume, percentage, and weight.

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing Paint code –Letters, numbers, or combination –Represents color of vehicle –Paint code location varies by vehicle manufacturer

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.)

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint code –Date of vehicle manufacture –Code may be same for different years

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint part number –Number assigned by specific paint manufacturer –Unique to each paint manufacturer –Different paint part number for each paint code

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint part number –Find paint part number with paint code Color chip book Paint code/paint part number CD Paint manufacturer’s web site

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Alternate paint part numbers –Same paint code –Slightly different color on vehicle –Reasons for different colors Vehicles built at different factories Different paint manufacturers Spraying conditions, equipment at factories are different

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Alternate paint part numbers –Alternate deck of color chips –Check chip against vehicle –Select best matching alternate

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Alternate paint part numbers –Underhood color Similar to exterior color Lacks metallic or pearl

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint sources –Jobber Sells paint Mixed by jobber Sells factory-pack color paint Supplied by paint manufacturer –Intermix Mixed at shop Uses tints supplied by jobber

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint mixing equipment –Digital scale Weighs tints Accurate to 100th of a gram Digital readout Zero scale by pressing bar

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint mixing equipment –Tint mixing bank Stirs and stores tints –Paint shaker Stirs tints

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint mixing supplies –Tints High-strength Low-strength Powder pearl Metallic tint

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint mixing supplies –Binder Forms paint film when dry –Balancer Corrects ratio of pigment to binder Flake control

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint mixing supplies –Comprehensive tint system Add tints to create paint –Single tint system Add tints, binder, and balancer to create paint

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint formula –Recipe for specific color –List of tints –List of weights of each tint

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Paint formula –Quantitative formula Lists required weight of each tint –Cumulative formula Lists weight of entire mixture as each tint is added

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Color creation –Stir tints for 15 minutes twice per day –Stir new tints for 30 minutes –Stir tints five minutes before mixing color –Do not mix waterborne paint in metal cans –Remove dried tint from pour spout

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Color creation –Recheck tint number before adding to can –Concentrate while pouring –Add tints to center of can –Start with clean paint can –Follow formula –Add specified amount of each tint

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Mixing (Cont.) Overpour –Add too much of one tint –Remove excess tint –Some scales can recalculate Paint can label –Contains safety information –Lists paint part number –May attach printout of formula

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction Stirring –Paint must be uniform before reduction –Heavier paint components settle out –Scrape solids off bottom if settled –Do not shake waterborne paint –Seal lid in place –Unsealed lid allows solvents to escape

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Reducer type –Match to spray booth temperature 60  – 70  F low-temp reducer 70  – 85  F mid-temp reducer Above 85  F high-temp reducer

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Hardener type –Temperature rated –Intended usage rated –Surface cure Amount of time paint will stay wet Absorb overspray

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Hardener type –Spot-rated Fast surface cure –Panel-rated Intermediate surface cure –Overall-rated Slow surface cure

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Viscosity –Thickness of paint –Measure with viscosity cup –18 – 22 seconds for most paints

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Viscosity –High-viscosity value Paint too thick –Low-viscosity value Paint too thin –Sprayable range

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) –Part reduction –Percentage reduction –Combination volume reduction

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Volume reduction Part reduction –Instructions given as ratio For example, 4:1 = four parts (units) of one substance to one part of another substance –Mixing stick Contain lines indicating units Must have straight-sided container

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Part reduction using mixing stick with equal increments marked (4:1:1 mixing ratio)

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Part reduction using dedicated paint mixing stick

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Part reduction –Graduations Units on paint mixing stick –Mixing cup Has various mixing ratios Select correct ratio

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Percentage reduction –Uses percent of volume Combination volume reduction –Uses both parts and percentage

Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Paint Reduction (Cont.) Weight reduction –Use scale –Weigh out components –Produces desired volume of paint –Volume mixing ratio cannot be used