The belt sander can achieve different grinding effects mainly in the following ways:
Selection of sanding belt
Grit size: The grit size of the abrasive belt is one of the key factors that determine the grinding effect. Abrasive belts with coarse grit (such as 60-80 mesh) have strong cutting ability and are suitable for quickly removing a large amount of excess on the surface of the material, such as the initial grinding of the rough casting surface, which can quickly grind the protrusions. Abrasive belts with fine grit (such as 220-320 mesh) are used to obtain finer surfaces, such as the final fine grinding of the surface of wooden furniture to make the surface smooth and flat.
Grit material: Different materials of grit will also affect the grinding effect. Common ones are aluminum oxide grit and silicon carbide grit. Aluminum oxide grit has good toughness and is suitable for grinding metal materials with higher hardness, such as stainless steel and alloy steel. Silicon carbide grit has high hardness and sharp cutting ability, and has better grinding effect on brittle materials such as glass and ceramics or hard alloys.
Adjust the speed
The speed of the belt sander has a significant impact on the sanding effect. Higher rotational speeds (within a safe range) can increase the cutting efficiency of the abrasive belt and make the sanding process faster, but may leave deeper scratches on the material surface. This situation is suitable for rough machining or grinding operations that do not require high surface quality. A lower rotational speed will make the cutting effect of the abrasive belt relatively gentle, which is suitable for polishing fine parts or easily deformed materials. It can obtain a more delicate surface and reduce the damage to materials caused by vibration and heat generated by high-speed rotation.
Sanding pressure control
The amount of pressure applied to the abrasive belt determines the depth of the grinding. Higher pressure will cause the abrasive belt to cut deeper into the material, achieving the effect of rapid material removal, and is often used to remove thick oxide layers, rust or old paint layers. However, excessive pressure may cause the abrasive belt to wear too quickly, or even damage the surface of the material. Lower pressure, fine abrasive belt and appropriate speed can be used for gentle polishing or fine grinding of the surface, such as grinding the housing of precision instruments or decorative parts.
Grinding method and path
Using different sanding methods and paths can also produce different effects. For example, for large-area surface grinding, the belt sander can be made to reciprocate in a straight line along the material surface to ensure uniform surface grinding. For curved surfaces, it is necessary to adjust the angle and motion path of the belt sander according to the curvature so that the sanding belt fits the curved surface to obtain a smooth and continuous grinding effect. For edges or corners, you can use the edge part of a belt sander or a special small belt machine for targeted sanding to avoid over-sanding other parts.
