Centerless grinders are one of the more unique types of grinders that are used in the fabrication industry. It utilizes a spinning blade to grind continuously in a counterclockwise direction for a continuous grind, similar to the way a blender works. Although they look like an alien machine, it is actually very simple to use. They are commonly used for precision surface grinds, fine burrs and other types of grinding.
The work piece to be ground is put into the top of the chuck, and the work blade spins in a counterclockwise direction. The material to be printed passes through the grinding device, while the blade gently grinds the workpiece to create an evenly ground product. The reason this type of grinder is called centerless is because it doesn’t use the cutting edges to create the grind perimeter. Centerless grinders are typically used for precision surface and flat grinding, but they can also be used on larger pieces of metal that have a high roundness to them.
A centerless grinder consists of two major components: the chopping wheel and the workpiece. The wheel is attached to the machine with an arm that has a slot to attach to the work. This slot then fits into a notch on the cutting surface of the chuck. The arm of the cutting wheel has a slot to secure the workpiece while it is being printed.
Because of their unique design, a centerless grinder requires some very precise machine setup in order to ensure consistent and reliable operation. To ensure a clean, even surface, the machine setup must always start in the same position as the diamond in the middle of the grinding wheel. To provide a consistent grind, the wheels should be turned at exactly the same speed each time the blade is engaged in turning. Machine setup should also ensure that the work is properly grounded.
Centerless grinders are particularly suited to producing extremely low roundness diamond parts because the design eliminates the need for a grinding wheel lock. Because of this, the grinding surfaces of the centerless grinder can be designed to produce extremely low chatter and minimum surface finish erosion. Unlike other types of diamond cutters that use a locking action to secure the work, the centerless grinder utilizes a sliding motion to secure the workpiece against the grinder. The sliding action will not only reduce chatter but also create a smooth workface finish. Because the centerless grinder has no moving parts, it requires minimal cleaning and maintenance.
Centerless grinders are also preferred for applications where the operator needs to quickly alter the workpiece or cut the workpiece to an alternate direction without changing the grinding angle of the machine. For example, it may be necessary to move the workpiece to the right for cutting a square, but to the left for the purpose of making a rectangular shank. In this case, the distance between the two cutlines on the shank is greater than the distance between the two cutlines on the end of the piece so the workpiece is moved to the right by the addition of a rotation to the machine. These rotations are typically performed at high speeds and with a large amount of manual work. Although these units are used frequently in applications that require speedy temperature changes, they do not require a large amount of maintenance. A small amount of oil is usually sufficient to lubricate and protect the moving parts during normal operation.