Painting in Vancouver: Causes of Failure
Vancouver’s Best Painters
CAUSES OF FAILURES
The following is a brief description of some of the causes of premature failures, which may result from substrate conditions, paint material, surface preparation, application, and underlying moisture.
SUBSTRATE VARIABLES
The substrate, or base material over which the coating is applied, may be suitable for some coatings and unsuitable for others. For example, an epoxy coating that may work well over concrete and steel may fail when applied over wood because the wood expands and contracts too much. Similarly, an alkyd coating that is suitable over wood and steel may fail over concrete due to the high alkalinity of concrete. Many substrates can be painted, and each has its own characteristics, including hardness, porosity, flexibility, coefficient of thermal expansion, roughness, pH level, and moisture sensitivity.
COATING MATERIALS
There are many generic coating types. Even within the same generic type, different solvents and pigments can be used to manufacture a paint with modified application and performance characteristics. Just as no single coating material can be expected to resist all environments, no one coating material can be expected to work on all substrates, with all types of surface preparation methods, and in all kinds of weather conditions.
Coating materials are generally formulated to be applied under specific conditions, to specific substrates, and with recommended surface preparation methods. Deviation from the recommended conditions or usages for the paint may result in failure.
On rare occasions, coating failures may be caused by a manufacturing error. When developing a paint, manufacturers test a number of different coating formulations and decide upon the best formula based on cost, performance, ease of application, and other factors. Once that formulation is determined, the paint is made in batches, often consisting of 50 to 1,000 gallons or more.
Resins, pigments, and solvents are added to the batch according to the paint formula. If all of the ingredients are carefully screened for quality, weighed, mixed, and added to the batch as planned, the paint will be consistent with other batches and with the original formulation. However, if any of the ingredients are defective (for example, an improperly-compounded resin) or if something should go awry in the manufacturing process (such as the addition of the wrong pigment or solvent blend), uniformity is not maintained, and a particular batch will be different from other batches. The properties of this batch may cause problems during or after coating application.
Rick Anderson
www.vancouversbestpainters.com
www.vancouverindustrialpainter.com
local: 604-PAINTER Toll Free: 1-800-PRO-PAINTER
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