The effect of surface roughness on the performance of finishes. Part 1. Roughness characterization and stain performance.

TLDR

The study examined how wood surface roughness affects coating performance. Surface roughness of five categories on three wood substrates was measured with stylus tracers and characterized by multiple parameters. Sanding improved paint performance, requiring less paint and yielding superior coverage even on low‑grade wood.

Abstract

In this study, the relationship between the morphological structure of the outside wood layer expressed as surface roughness, and the performance of coatings was analyzed. The surface roughness of five roughness categories (processed by planing, sanding, and bandsawing) on three wood substrates (vertical- and flat-grained western redcedar and flat-grained southern yellow pine) was determined by stylus tracer measurements. Several surface parameters were calculated to characterize the five roughness grades. Surface sanding proved to be an advantageous processing step prior to paint application. Sanded surfaces needed a relatively low quantity of paint for coverage and showed best paint performances even on low-grade wood.