Types of paint.

• "Single pack" paint.
  • A "single pack" or "single componet" paint is a paint that does not need a hardener to be added to it.
    
  • Simply apply it and let it dry.
    
  • On the plus side: Single pack paint is easy and convenient to use.
    
  • On the negative side: it's softer, easier to scratch and, in general, is less durable than "two pack" paint.
    
  • Aerosol paint cans are a single pack paint.
• "Two pack" paint.
  • "Two pack" or two component paint requires a hardener to be added to it before it is applied.
  • Usually you should add two parts paint to one part hardener (this is not always true).
  • Once the hardener has been added to the paint it will go hard after a few hours, even if it's kept in a sealed container.
  • The amount of time that the paint can be sprayed after the hardener has been added depends on the speed of the hardener, it's usually 2 to 6 hours.
  • On the plus side: two pack paint is a high quality and durable paint.
  • On the negative side: two pack paint is expensive and it's slightly harder to spray due to it's higher viscosity (although it can be thinned).
  • Two pack paints are not available in aerosol (since they would go hard in the can after a few hours).
• Solid colour paint.
  • Solid colour paint is simply pure colour that does not have a sparkle or and any special effect to it.
  • This coat is Usually a finish coat and a coat of lacquer in not required.
  • This type of paint is usually available in single or two pack.
• Metallic base paint or Pearlessent base paint.
  • These types of paint have a sparkle, a spec of different colour or some kind of special effect to them.
  • This type of paint is a base coat and not a finish coat, a coat of lacquer is absolutely required on top of the base coat.
  • Sometimes this painting system is referred to as "clear over base": clear refers to the lacquer and base refers to the base (mettalic) paint.
  • This type of paint is usually available in single or two pack.
• Lacquer (clear coat)
  • This is a transparent coat usually applied over a base colour.
  • This type of paint is usually available in single or two pack.
  • Spraying lacquer requires a high degree of skill.

Thinners

• Thinning a paint will reduce it's viscosity (high viscoity means very thick).
• Thinning a paint will make it easier for the spray gun to completely atomize the paint.
• Thinning a paint will increase it's volume and enable you to apply thinner coats thus increasing the potential coverage area
• The more you thin the paint the easier the paint will sag.
• There are different speed thinners: Fast, medium and slow (the speed refers to how fast the thinner evaporates).
• "Flash off" time refers to the amount of time between coats.
• Too slow a thinner will mean longer flash off times (flash off also depends on shop temperture).
• Too fast a thinner will mean the paint will start to dry before your finished spraying.
• On an extremely hot day you should use slow thinner
• On a cool day you should use fast thinner (consult U-POL guide).

Spray painting

• Most paints can be sprayed at 4 bar, although high viscosity paints may require a higher pressure to ensure complete atomization.
• When spray painting a surface "atoms" of paint land on that surface, you should continue to apply paint until the "atoms" all join together to form a smooth uniform surface, if the paint is too dry (not enough thinner) then it will be impossible to get all the "atoms" to join up, thus a rough finish will result.
• The more thinner you use the easier it will be to get the "atoms" to join up to form a smooth surface and the paint will be easier to atomize.
• It can be extremely difficult to judge how much paint to apply (especially with lacquer).
• If you apply too light a coat then the "atoms" of paint won't join together to form a uniform surface (finish will be rough and will have little shine).
• If you apply too much then the paint will sag.
• The less experience you have the more you should thin the paint (although this may result in very thin coats).
• Spray guns come with many different diameter nozzles, the nozzle you should use depends on the viscosity and flow characteristics of the paint.
• The larger the nozzle the more paint will be delivered at a given pressure.
• Consult your paint supplier for a reccomended nozzle diameter for a particular paint.
• Summary: Spray at four bar, thin the paint, spray until surface becomes wet.

If you would be content with single pack paint then buying it in aerosol form is probably the best way to go.
However, if you would like to spray two pack paint then you will need an air compressor with pressure control, filter and water trap and a good quality spray gun.
A good quality spray gun should "atomize" the paint completely and never "spit" the paint.

Spray paint tips.

• For tips and instructions on how to spray paint visit the U-POL website by clicking here.