Investigating the Sanding Process of Medium-Density Fiberboard and Korean Pine for Material Removal and Surface Creation

Jian Zhang,Feng Cheng,Bin Luo,Li Li,Junhua Ying,Hongguang Liu

doi:10.3390/coatings8120416

Abstract

As an important fine machining method, sanding operation is widely used in most engineered materials. In wood sanding, high material removal rate and surface quality are expected. Clarifying the material deformation in the sanding process is the key to improving sanding efficiency. In this study, a single grit scratching method is used to investigate the material removal and surface creation of medium-density fiberboard (MDF) and Korean Pine (Pinus koraiensis Sieb.et Zucc). It is found that there are some differences in the material deformation during scratching Korean Pine and MDF, compared with grinding metals. A mechanism based on the anatomical cavities absorbing effect was proposed to account for the differences. This mechanism helps to explain why tiny, or even no, “pile-up” (like swelling ridges created by the ploughing effect) occurs during scratching Korean Pine, especially in longitudinal direction. MDF as a densified wood composite presented more pile-up and the variation of pile-up ratio was investigated. The porosity and wood grain direction exert great influence on material removal and surface creation in wood sanding. At the rubbing stage, a new method was developed to confirm the elastic spring back effect both in MDF and Korean Pine scratching. The results obtained and the approaches used in this paper could provide insights into the material removal and surface creation research of other wood species and wood composites to finally improve sanding efficiency and surface quality.

Highlights

Wood materials are widely used in floor and furniture manufacturing
The material removal and surface creation process of sanding medium-density fiberboard (MDF) and Korean Pine was studied with single grit scratching tests
It is found that there are some differences in the material deformation during scratching Korean Pine and MDF

Summary

Introduction

Wood materials are widely used in floor and furniture manufacturing. As an important fine machining method, sanding of wood is usually the last operation of surface modification before gluing and painting, which aims to improve surface quality and ensure dimensional accuracy [1,2,3]. There are not many systematic studies on material removal and surface creation in wood sanding operation. Stewart studied some surfacing defects and problems related to wood moisture content [4]. He proposed that the defects commonly associated with sanding operations are fuzzy or raised grain, crushed or burned surface, and moisture content exerts great influence on it. Grain raising like lifting of fibres in wood was deeply researched by Evans et al [5]. They clarified the relationship between wood density and grain raising. Koehler observed that sanded wood surface was more susceptible to grain raising than planed wood surfaces [6]

Methods

Results

Conclusion