Definition - What does Alligatoring mean?
Alligatoring is the large formation or pattern of shallow and deep cracks, which look like the skin of an alligator or crocodile on the surfaces of:
- Paint with limited flexibility, excessive thickness, top coat that did not bond well or shrunk faster than the underneath layer
- Hard paint over a softer or partially dried undercoat/ primer
- Bitumen, asphalt
- Other coating materials that have been overexposed to the environment or are too old
Alligatoring is also called crocodiling or chip cracking.
Corrosionpedia explains Alligatoring
Alligatoring on a coating surface is a warning that it is losing its ability to prevent water and other corrosive substances from penetrating the substrate or the surface that the paint is supposed to protect. It also means that whoever is responsible for the maintenance of the painted surface or structure should start thinking of a repainting job.
Water that seeps on small superficial cracks can degrade the coating further as it expands when it freezes, and expands or contract when it thaws. The cracks become bigger as more cracks are formed, until water finally reaches the base surface.
Alligatoring is bound to happen if the coating is already beyond its usable lives. After many years, the coating loses its resiliency to withstand the effects of exposure to extreme temperatures, ultraviolet rays and other environmental conditions.
The problem is premature alligatoring, which means higher maintenance costs. Coating experts advise the following to keep the coating surface in good condition during its expected lifespan:
- Good workmanship, which means: no shortcuts, applying a coating only after the previous one is thoroughly dry, correct mixing of materials, excessive thickness and more according to the manufacturer's’ instructions.
- Using compatible coating materials.
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