Centerless grinders are a popular type of milling machine due to their flexibility and robustness in handling heavy materials. These machines allow for the removal of large areas of material with one single cut, making them ideal for applications requiring heavy material manipulation. Due to their unique design, centerless grinders require a steady hand and precise techniques to ensure the finest cuts possible. When properly used, a centerless grinder can create more accurate results than any other grinding technique.
The most basic of these machines has a revolving disc on the top of a tumbler housing containing powder. In order to operate, the operator places the rotating disc into the tumbler housing at the same time pushing the opposite sides of the tumbler towards the grinding wheels. The tumbler is returned to its original position after the grinding process is complete.
To achieve maximum power output from the centerless grinder, the operators should place the hand on the workers while sliding the grinding wheels together. At this time the workers must be located near the center of the wheel. The workers should be pushed up slightly to make room for the grinding wheels to pass over the abrasive. Once the workers are located on the wheel and is pushed up to its highest position, the operator should rotate the grinding wheel and continue to push on the workrest while the wheels passed across the abrasive.
Because the entire operation of a centerless grinder is controlled by the operator, it is imperative that proper operating procedures are observed. First, the machine should be turned on and preheated prior to use. The heat generated during operation should be adequate to meet the lubrication unit, but not hot enough to cause damage to the moving parts. After the preheating process is complete, a coolant flush should be pumped through the engine at regular intervals. If the engine is overheated, additional air cooling components should be added to the engine system.
After completing the steps necessary for starting the motor and warming the engine, the workpiece should be lined up with the motor at its center. The tooth pattern of the grinder will vary slightly based on the type of material being ground. For example, the centerless grinder is set up to grind fine jewelry wire. A fine wire is not the only item that can be ground with this type of grinder; therefore, it is important that the workpiece is perfectly straight and aligned with the motor to ensure consistent results. It is important to make certain the angle of the workpiece is evenly distributed across the front and back of the motor so that the wheel head will contact both sides of the inside of the workpiece at the same time. If the tooth pattern includes raised areas, this will cause uneven contact.
After lining up the tooth pattern and the motor, the workers should be firmly pressed into the table with enough force to hold it in place and to avoid slipping. The workers should then be held in place and firmly centered in the worktop or workpiece with a pair of reference pins. The motor should now be energized. The centerless grinder should now be securely positioned in the workers, with the workers and worktop firmly centered in the worktop, and the tooth pattern and wheel axis positions correctly identified.