Effect of Sanding on Surface Properties of Medium Density Fiberboard

Abstract

The objective of this research was to investigate the effects of sanding on the surface properties of the medium density fiberboard (MDF) panels made from Rhododendron ponticum L. wood. The MDF panels were sanded with different sizes of the sand paper grit: 60-, 60+80- or 60+80+120-grit. Surface absorption and surface roughness al the MDF panels were determined based on EN 382-1 standard and ISO 4287 by using a fine stylus profilometer respectively. Sessile water drop technique was used to determine contact angle values of the panel Sillftlee. The results indicated that sanding process improved the sum face smoothness of the panels. However the wettability and surface absorption of the panels were negatively affected by increasing grit size. The MDF surface sanded with 60-grit size had a lower contact angle, more wettable surface, compared to those that were sanded with 60+80+120-grit size. For example, the average contact angle value of the panels sanded with 60-grit sandpaper was 43.3 degrees as compared to the panels sanded with 60+80+120-grit sand paper which was 76.1. The rougher surf. ace was more wettable and absorbent compared to smoother surface. Based on the findings obtained from the present study, sanding has a significant effect on the wettability, surface roughness, and surface absorption af the MDF panels, which could provide useful infarmatkm on the bonding and finishing of the MDF panels.