What To Consider When Thinking About Solid Carbide End Mill Machining
The selection of geometries and coating for solid carbide end mills can be a confusing, but evaluating the operation will determine which end mills are best for the job.
One of the most confusing aspects about using solid carbide end mills is the selection of many types of geometries and coatings. By understanding what geometries and coatings can or cannot do makes selection as easy as one, two, three. When first deciding which end mill to use, thoroughly evaluate the operation along with the material that needs to be employed to get the desired shape needed. The next step is deciding what geometry will work best.
For example, when doing a slotting operation, unless doing a light cut of about .2D or less, it is best to use a two- or three-fluted end mill. The general rule is use less flutes for deeper cuts, with four or higher flutes for light cuts. The reason for this is the venerability of chip packing that can lead to destruction of the end mill. If the machine and program have the ability to trochoid mill, a method which is done by engaging circular arcs using an end mill smaller than the slot width, a larger number of flutes can be employed. Since the end mill is basically periphery cutting, less heat and forces allow for longer tool life, higher tolerance finishes and increased production over the same amount of time it would take using the conventional method.
When a periphery cut or side mill operation is part of the application and metal removal is of concern, employ a larger number fluted end mill with four, six, even eight teeth.
Knowing the basics of geometries and coatings and understanding what they can and cannot do is the first step to helping you decide which end mill should perform best for your application.