I’ve recently been scratching my head over issues that are so rare that it took some digging through contacts to resolve. Here is the full explanation of diagram of a phenomenon know as Benard cells:
Bénard cells: differences in surface tension
To achieve good flow, the surface tension must remain uniform over the complete surface of the coating layer whileit is drying. During the drying of a solventborne coating film, the solvent on the surface evaporates causing differences in temperature, surface tension, solvent concentration and density within the film. To balance the thermodynamic disequilibrium currents occur in the coating film. These currents produce eddies in the drying layer, a phenomenon known as the formation of Bénard cells. The surface tension ishigher at the edges of the cells than at their centers and coating material flowsfrom regions of lower surface tension to regions of higher surface tension. The resulting unevenness in the surface dries into the coating film. This produces an irregular surface as the coating shows marked texture.
I wanted to simply post about this phenomenon as a way to let people know that floor finishing can be a very tricky business and so many variables apply to coating a floor that it is often unfair to blame contractors for an issue this rare. It took a number of phone calls to various experts in the field to uncover this phenomenon and an appropriate fix. This is a case where even my experience was not enough. My network was the real strength in resolving the matter.
Problems will happen with any hardwood floor during installations and wood floor refinishing. The goal is to minimize the number of problems and if they do occur, then to quickly arrive at an answer to expedite the fix and get homeowners back in the home with minimal impact on their life. If we had approached the issue with recoating the floor, then the problem would likely have been the same with each attempt. We were able to fix the problem with a minor buffing with a polishing pad in a couple of hours.