Techniques for Successful Spray Coating Application
Good quality spray coating finishes are only accomplished by means of correct procedures and motions.
For a successful outcome each time the following tips should be observed.
Always start with a suitable substrate. Correct any substrate defects before starting to coat, as any visible defect may show through to the final coated finish. Do not rely on the coating to hide substrate defects as it is not their function. Good preparation is the key to a flawless finish.
Select the best type of coating application equipment to achieve the desired coating finish. This will depend on a number of factors, primarily the coating to be used and the environment it is to be sprayed in.
Learn the correct setup procedure for the particular spray equipment to be used and adjust gun settings to achieve a correct fan pattern.
Always thin product to be used to the recommended viscosity.
When applying the coating use an even stroke where the gun moves parallel and at 90° to the surface. The distance from the fluid head (approx. 15-25cm) to the surface to be sprayed should stay uniform throughout the stroke, with the speed of the stroke staying constant throughout the pass. Each stroke should overlap the previous stroke by 50% to achieve an even application of the coating. Moving the gun too fast and not overlapping could result in orange peel and streaking can occur. Holding the gun too far away from the surface can cause excessive dry spray and holding the coating too close can result in runs, sags or flooding. The most obvious fault that occurs is the arcing or tilting of the gun, as shown below. Download the Technical Bulletin.