- Tool and Cutter grinder
A tool and cutter grinder is used to sharpen
milling cutters and tool bits along with a host of other cutting tools.
It is an extremely versatile machine used to perform a variety of grinding operations, surface, cylindrical, or for the grinding of complex shapes. The image shows a manually operated setup, however highly automated Computerized Numerical Control (
CNC) machines are becoming increasingly common due to the complexities involved in the process.
The operation of this machine (in particular the manually operated variety) requires a high level of skill. The two main skills needed are: 1. understanding the relationship between the grinding wheel and the metal being cut 2. knowledge of tool geometry. The illustrated set-up is only one of many combinations available, the huge variety in shapes and types of machining cutters requires flexibility in usage. A variety of dedicated fixtures are included that allow cylindrical grinding operations or complex angles to be ground. The vise shown can swivel in three planes.
The table moves longitudinally and laterally, the head can swivel as well as being adjustable in the horizontal plane, as visible in the first image. This flexibility in the head allows the critical clearance angles required by the various cutters to be achieved.
CNC tool and cutter grinder
Today's tool and grinder is typically a CNC machine tool, usually 4, 5, or 6 axes, which produces endmills, drills, etc. which are widely used in the metal cutting industry.
Tool and cutter grinders can be adapted to manufacturing precision machine components. The machine, when used for these purposes more likely would be called a CNC Grinding System.
CNC Grinding Systems are widely used to produce parts for aerospace, medical, automotive, and other industries. Extremely hard and exotic materials are generally no problem for today's grinding systems and the multi-axis machines are capable of generating quite complex geometries.
A radius grinder (or radius tool grinder) is a special grinder used for grinding the most complex tool forms, and is the historical predecessor to the CNC tool and cutter grinder. Like the CNC grinder, it may be used for other tasks where grinding spherical surfaces is necessary. The tool itself consists of three parts: The grinder head, work table, and holding fixture. The grinder head has three degrees of freedom. Vertical movement, movement into the workpeice, and tilt. These are generally set statically, and left fixed throughout operations. The work table is a T-slotted X-axis table mounted on top of a radial fixture. Mounting the X axis on top of the radius table, as opposed to the other way around, allows for complex and accurate radius grinds. The holding fixtures can be anything one can mount on a slotted table, but most commonly used is a collet or chuck fixture that indexes and has a separate Y movement to allow accurate depth setting and endmill sharpening. The dressers used on these grinders are usually quite expensive, and can dress the grinding wheel itself with a particular radius.
The D-bit grinder is a
tool bitgrinder that specializes in the grinding of D-bit cutters for pantographmilling machines. Pantographs are a variety of milling machine used to create cavities for the dies used in the molding process, they are being rapidly replaced by CNC machining centers.
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