How to Make a Rainbow With an Airbrush Gun

by Brenda Priddy
Wear a mask when working with non-edible airbrush paint.

Wear a mask when working with non-edible airbrush paint.

Jupiterimages/ Images

An airbrush gun is a tool you can use to make a large variety of projects. Airbrush guns have use in the clothing industry, car and body shops, hobby painting, cake decorating and other areas. All airbrush techniques are done similarly, no matter the base. An airbrushed rainbow is made the same when decorating a cake, car, piece of furniture or wall. Adjust the size of the rainbow according to the specifications of the project.

Items you will need

  • Airbrush gun
  • Airbrush paint, various colors (use edible paint for desserts)
  • Air tank
  • Degreasing cleaner
  • White cake icing
  • Vapor mask
  • Spray varnish
Step 1

Set the pounds per square inch (PSI) pressure gauge to 10 for cakes. Do not set the pressure to above 20 PSI, or you can blow holes in the icing, according to the Wilton website. The PSI can be between 30 and 60 for hard surfaces, according to the How to Airbrush website. Attach the air gun to the air tank. Fill the air sprayer with pink paint.

Step 2

Prepare the work surface. Ice a cake with white icing, and clean any other surface with a degreasing cleaner and soft cloth.

Step 3

Hold the spray nozzle about 8 inches away from the surface. Spray a thick arch onto the surface. This will become the top of the rainbow. Spray a smaller arch at the base of the first arch to make the bottom of the rainbow.

Step 4

Switch the color in the sprayer to yellow. Spray half of the top arch with yellow. Spray half of the area between the two pink arches with yellow.

Step 5

Change the color to blue. Spray blue over the bottom half of the yellow line, the empty space inside the rainbow and over the bottom pink line to create purple.

Step 6

Allow the paint to dry. Spray on additional layers of paint to make the colors bolder, or for a thicker coverage of paint.

Step 7

Coat the rainbow with a spray of clear varnish if spraying the design onto a non-edible object. Allow the varnish to dry for 24 hours.

Tips & Warnings

  • Always wear a mask when using an airbrush gun to avoid inhaling paint particles into your lungs.

Photo Credits

  • Jupiterimages/ Images