ASSEMBLY & PREPARATION
11
Your machine can work as both a milling and drilling machine, depending on the type of cutter that is installed.
Refer to the introduction below for some common cutter holders and cutting tools that you can install onto your
machine.
CUTTER HOLDER
The two most common cutting tools for the milling machine are drill bits and end mills. Drill bits are held in
place by drill chucks (one included), while end mills are held in place by either collets or end mill holders (not
included). Use the suitable holder for your cutting bit. The shank taper is R8.
•
Drill Chucks
The included drill chuck is ONLY able to hold drill bits for drilling operations. It is NOT able to hold milling
bits. For end milling or face milling operations, collets or end mill holders are needed.
• Collets (not included)
Collets are shorter than end mill holders to allow more vertical work area. It secures the end mill all the way
around the shank to provide a better grip. They are also less expensive than end mill holders.
•
End Mill Holders (not included)
End mill holders are longer than collets and so the cutter can reach closer to the machine’s worktable. The end
mill is secured in the holder by a set screw that bears on the flat shank of the end mill. Changing end mills is easier
to do on an end mill holder. They are also more robust than collets and are less prone to wearing out.
Collets, end mill holders, and drill chucks are held in the spindle by the drawbar (Part No. 210). The drawbar is
tightened from the top of the spindle and extends through the spindle to the holder/chuck. When tightening the
drawbar, make sure it is snug in the spindle threads, but do not overtighten.
CUTTING TOOLS
An end mill is the most common type of cutting tool for the milling machine. While a drill bit can only make
plunge cuts in the vertical direction, an end mill can cut from the side of the workpiece. Some can also make
plunge cuts.
•
End Mills
End mills can be classified into center-cutting and non-center-cutting mills. In a center-cutting mill, the flutes meet
in the center on the tip of the end mill. This allows the mill to be plunged into the workpiece as is done with a drill
press. In a non-center-cutting mill, the flutes do not meet at the tip, leaving a gap with no flutes in the center. The
non-center-cutting mill can only cut from the side of the workpiece. It is recommended to use center-cutting mills
for their cutting versatility.
End mills can also be classified into 2-flute and 4-flute end mills, identified by the number of flutes on the tip of
the mill. Commonly, 2-flute end mills are used for making bigger cuts or when cutting soft metals such as alumi-
num, as there is more room between the flutes to extract larger chips. 4-flute end mills can produce a better finish
because there are twice as many cutting edges, each taking off less material. These end mills are used more com-
monly on harder metal such as steel and brass.
• Drill bits
Drill bits can be used on the milling machine for it to function as a drill press. However, drill bits are not designed
to cut from the sides as they are not built to withstand the lateral forces imposed by sideways cutting.
DO NOT USE A DRILL BIT IN PLACE OF AN END MILL.
