When sanding, choosing the right sanding tools is crucial. People often talk about job power, pad hardness, and the right abrasives. They often fail to mention the most important thing: the correct sanding motion!
Based on the surface quality and desired results, there are various grinding actions to choose from for both rough and fine grinding. The longer the grinding stroke, the more material is removed. For example, a smaller grinding stroke of 3 mm is ideal for fine grinding. A grinding stroke of five to seven millimeters will remove a significant amount of material for rough grinding.
Linear grinding
Grinding motion: pure linear motion.
Application: Linear motion is highly suitable for sanding wood along its grain.
Note: Linear sanding along the grain will not damage the wood fibers (which is important, for example, if oil, wax, or a thin layer of varnish is to be applied to the surface). The linear sanding motion does not spread to the sides; therefore, linear sanders are ideal for sanding frame sections adjacent to glass panes.
Eccentric grinding
Grinding motion: Oscillating motion, combining overlapping linear and circular motions.
Application: Use when the quality of sanding is not critical (for example, if a topcoat is to be applied afterwards).
Note: The triangular sander also exhibits oscillatory motion. It is ideal for removing material from surfaces with small corners, angles, and edges.
Eccentric rotary grinding
Grinding motion: After connecting to the gearbox, it undergoes forced eccentric rotation.
Application: Gearboxes significantly enhance the material removal rate, making them ideal for rough grinding and the rapid removal of old paint layers that are otherwise infeasible
Note: Quickly remove a large amount of weathered paint and varnish layers without the high risk of sanding errors. Eccentric rotation can also be used for polishing.
Rotary grinding
Sanding motion: Pure rotational motion
Application: Use where rapid removal of a large amount of material is required (such as when stripping large areas of paint).
Note: A powerful rotary sander does not tolerate any user errors. When processing on a workpiece that needs to be completely level, it can accidentally produce deep sanding marks.