What Are End Mills, What They're For, and How to Use Them
Surely, in some specialized mechanical workshop you've noticed the precision face mills. They resemble drill bits but are short and look broken. Without the final part. Actually, this is precisely the ideal shape for carrying out the process.
These tools, in fact, don't have the task of drilling metal or making a hole in wood. They don't even need to proceed on reinforced concrete (here's a guide to do it). We need to work on the removal of unnecessary material according to certain standards, milling is a machining operation that serves not only to remove excesses but also to create specific shapes. Do you want to go deeper?
What Are Face Mills, Definition
The face mill is a tool that allows you to operate on a block through a particular milling operation. In this case, it's not the side of the tool that operates, but the face. In this way, it's possible to intervene on the bases vertically. This activity can be performed manually or with high-speed precision machines.
Obviously, in the latter case we don't need to worry about time and output quality since everything is set through digital commands. Basically, face milling is used to finish flat surfaces with extreme precision, and the mill is positioned so that its face perpendicular to the axis of rotation is in contact with the workpiece.
What's the Difference with Peripheral Mills
The latter allow intervention with another type of milling, where the cut is promoted by the teeth on the circumference of the tool. In face milling, as mentioned, the cut is performed primarily by the teeth you see on the face that touches the workpiece perpendicularly. It should be added that with certain face mill models, the sides can also intervene.
For example, there are face mill end mills (similar to a drill bit) with final elements of different shapes and adapt well to surface milling and side milling. Shell mills have a larger diameter and adapt to the need to work on a large amount of material. While fly cutters have a single cutting tooth and are perfect for precision work.
How Is a Face Mill Constructed Technically
Let's analyze how a face mill is defined from a structural standpoint. The aesthetic appearance is similar to that of a drill bit, but you'll immediately notice there are some substantial differences, and much depends also on the type of tool we're looking at. First, the mill in question can have cutting edges on its face and often along its circumference.
Usually, these tools are made of high-speed steel (HSS) or tungsten carbide to resist wear and high temperatures. Which solution to prefer? The first option is still resistant and more economical, but suitable for medium-intensity machining, while the second choice is perfect for those who need to work on particularly hard materials for extended periods. The cutting edges are designed for rapid and effective chip extraction, to avoid holdups and overheating.
Which parameters to consider? First of all, the coating: possible support of titanium nitride (TiN) adds great resistance on intense work with hard materials. Furthermore, the diameter of the mill and the related amount of removed material that varies from a few millimeters to over 3 decimeters, number of teeth (lower for difficult materials, higher for fast machining), cutting depth.
What Can a Face Mill Do?
The operations that can exploit the activity of a face mill are diverse. It ranges from flattening and surface adjustment, which involves a homogeneous pass over the entire base to make it aligned and free of imperfections, to the removal of a certain amount of material to eliminate entire blocks. Then there can be finishing operations.
They are used to carve pockets and slots, or to create corners. You can work on large areas or aim for small high-precision operations: it all depends on the type of mill you use. And on the attachment of the face mill you've chosen to configure everything with the machine.
