Centerless grinders are a special type of grinder that has the grinding teeth situated in a disc, which is then placed inside a chuck or die and is spun around by a powerful electric motor. Because the grinding teeth are not located in contact with any other surface, there is little or no interference from neighboring metals during the grinding process. Centerless grinding is also a very convenient machining procedure which makes it ideal for use on a wide variety of jobs.
Unlike traditional “through-feed” and “center-feed” grinders, a centerless grinder will not spin through the work. The workpiece will be ground in one cycle, then the grinding wheel will cease and rest while a magnetic force is used to align the teeth of the grinding wheel with the work surface. The work will then be ground again, and the process will continue until all of the material that was ground in one cycle has been removed. The entire operation requires very little manual labor, and the speed at which the grinding wheel works is typically greater than four hundred revolutions per minute. This type of machine is ideal for small projects such as plastic crafts, jewelry, woodworking, and various other woodworking processes.
In addition to the use of a stationary workholder to protect the grinding area from interference, the use of a centerless grinder also allows for the use of a safety workers. These are typically made out of a hard plastic, metal or even wood and are attached to the worktop or workbench with screws. These workrests provide a strong support for the worker as they perform the necessary tasks. The two types of wheels that a centerless grinder will typically use are:
o Standard: The most common style of centerless grinder is the standard wheel. These machines utilize a small jackscrew connection to the spindle arm to connect the machine to the workhead or workbench. The small Jackscrew connection is not often used because it increases setup time on these machines but there is an alternative method that can be used called the Schlatter style connection, which does not require a jackscrew connection.
o Imt. The Imt. refers to the in-set or preset speed that the machine will operate at. There are many manufacturers that have developed their own unique set of speeds, which means that when you purchase your centerless grinder, you will want to check the speed of the machine to ensure that it will work properly for the type of work that you will be doing on it.
o Spindle: The other major component that is used in a centerless grinder is the spindle, which is the part that connects the workpiece to the machine. There are two types of spindles that a grinder can use; a tapered spindle, and a solid disc or wheel spindle. The type of spindle that is chosen will depend upon the workpiece that are to be cut, the type of cutting procedure that will be done, and the diameter and roundness of the workpiece that is to be worked with.