What are some causes of loss of adhesion?
Poor sanding
- Lack of raw wood sanding (white wood sanding)
- Lack of intercoat sanding
Inappropriate uses of stain
- Oily stains were not adequately dry prior to first coat of finish (often caused by not removing excess stain after application
- Shading or toning with only stain leads to pigment obstructing a mechanical bond (suspending stains in a thinned topcoat can help adhesion)
Incompatible systems
- Using a softer sealer coat can lead to wrinkling or cracking in the topcoat.
Example: Using a nitrocellulose sealer beneath a conversion varnish topcoat.
What are some causes of poor atomization?
- Too little fluid pressure under-atomizes the material
- Too large of tips deposit too much under-atomized material
- Worn equipment causes unequal distribution of sprayed material
- Viscosity that is too high for equipment leads to poor atomization and lack of material
- Basketballs vs. Marbles
- Finer atomization leads to better hide and film development
- Larger particles can hinder color development and proper film formation
Why am I not achieving consistent color?
Color vs. strength of color
- The color is correct, but not enough has been applied. Opaque colors that have not achieved full hide can look different
- Concentrates may not have been properly reduced, leading to too much color being applied
Raw Wood (white wood) sanding is inconsistent, leading to different amounts of stain deposited on the wood
What is causing fish-eyes on my project?
Most typically caused by surface contamination
Occasionally caused by poorly maintained equipment
- Oil in air lines is most common
- Silicone oil in lubricants could also be a source
Rarely caused by contaminant in product
