ENDMILL BASICS

Endmills are used for producing precision shapes and holes on a milling or turning machine. Many of our modern day products are created using some kind of endmill or cutting process. Without these tools cost-effective manufacturing would not be possible. Products today that cost a few dollars would cost hundreds if not thousands of dollars to make.

The correct selection and use of endmills is important with machining centers and lathes. Endmills come in a variety of design styles and materials to accommodate just about any job. Various coatings can be placed over the core material to extended the life of the tool as well as reduce the operating temperature and cooling requirements.

It is very important that the endmill be held firmly by the tool holder otherwise poor cuts and non-consistency can result. The best way to mount an endmill is in a concentric tool holder.

Basic list of endmill use:

FACE MILLING	For small face areas of relatively shallow depth of cut. The surface finish produced can be 'scratchy".
KEYWAY PRODUCTION	Normally two separate endmills are required to produce a quality keyway.
WOODRUFF KEYWAYS	Normally produced with a single cutter in a straight plunge operation.
SPECIALTY CUTTING	Includes milling of tapered surfaces such as 'T" shaped slots & dovetail production.
FINISH PROFILING	To finish the inside/outside shape on a part with a parallel side wall.
CAVITY DIE WORK	Generally involves plunging and finish cutting of pockets in die steel. Cavity work requires the production of three dimensional shapes. A Ball type Endmill is used for the finishing cutter with this application.

Climb Milling	Cutter direction for a milling operation. The cutter tending to "Climb" into the workpiece, relieving feed force requirements. First choice for CNC machining. Increases cutter tool life. Sometimes called down milling.
Conventional Milling	Cutter direction for a milling operation. The cutter tending to push the workpiece away from the part, increasing the required feeding force. First choice for manual machining. Sometimes called Up milling.
End Milling	Metal removal process that is achieved by feeding a workpiece into a revolving cutter. The cutter will remove material as chips.
Peripheral Milling	The machining of an edge surface of a part. Peripheral milling is accomplished by presenting the workpiece to the circumference or the periphery of the milling cutter.
Plunge Cut	Axial feeding into a part. CNC machine movement in the Z-axis direction. Direct plunging into the face of a part. Plunge feeding in a axial direction. Requires a center cutting End mill.
Ramp Cut	Axial feeding into a part. CNC machine movement in the Z axis direction and an additional axis ( X or Y ). Angled plunging into the face of a part, feeding in other than an axial direction. Requires a center cutting End mill. Ramp cutting will assist the end mill into entering into a part face.