Diana Tennyson

Spray Painting Cars

Spray painting a car is different than spraying paint on just anything else. Millions of cars are made each year and the car bodies must all be painted to prevent them from going rusty. The paint is sprayed onto the car bodies and the process is made more efficient by using electrostatic charge.

How This Works

Involved With Electrostatics

The paint spray goes past a high voltage positive needle as it leaves the spray gun and the tiny droplets of paint pick up a positive charge. This is the point where electrons are being lost. Since electrons are the only ones that can move, the car body is given a high voltage negative charge which attracts the positively charged paint droplets.
electrostatic spray painting

Improvement of Efficiency

1. The paint droplets spread out more as they leave the gun. This is because they get the same positive charged so they repel each other. This is efficient because the paint will cover a wider area more evenly rather than coming straight out of the gun.

2. The paint droplets are attracted to the negative metal car body, so less paint will be wasted by landing on the floor or the walls of the surrounding area.