The frame supports the machine and provides rigidity to resist cutting forces. Typically, there is a base with a detachable column.
CNC Milling Machine Frames are most commonly made of cast iron. Other possibilities include weldments with epoxy granite fill and aluminum.
The table is where a workholding solution of some kind holds the workpiece for machining.
Most milling machine tables use T-Slots to attach workholding to the table.
The spindle is the heart of any milling machine. It consists of a rotating assembly with a taper where tool holders may be installed.
A motor with optional transmission of some kind rotates the spindle.
The axes of a CNC Milling Machine allow motion using Cartesian coordinates programmed via g-code and via manual jogging from the control panel.
Generally, there are 3 axes that correspond to X, Y, and Z. An optional 4th Axis is an accessory for CNC Milling Machines. 5 axis milling machines are possible but not very common in the DIY CNC world.
The CNC Controller is the brains of the machine. It contains the electronics that drive the axis motors to move the axes.
CNC Controllers are responsible for accepting G-Code and manual inputs from the CNC Control Panel and converting that into the proper signals to control the Axis Stepper or Servo Motors.
CNC Milling Machine Accessories
CNC Coolant plays multiple roles in cutting and it comes in many forms. There are several types of coolant system common in DIY CNC including:
– Air Blast or Cool Air Gun
– Dust Collector
While a Dust Collector doesn’t “cool”, it satisfies the primary rool of Coolant which is chip evacuation.
CNC Milling Machines need lubrication for their leadscrews and especially their ways. Ways are whatever mechanism is used to allow the axes to slide.
Way Oilers can be manual or automatic. An automatic electric way oiler adds considerably to reliability by ensuring consistent friction and less wear on the ways.
Powered or Power Drawbars are a tremendous convenience for CNC Milling Machines and an absolute requirement if an Automatic Tool Changer is to be used.
Basically, they allow push button capture and release of tool holders from the spindle. There are three prevalent types including Impact Wrench, Tormach TTS Style, and Pull Stud.
Machines without a Power Drawbar require the operator to loosen the drawbar (or a collet depending on the spindle) with wrenches, which takes much longer than the push button style.
CNC Milling Machines are inherently messy beasts. They will throw chips long distances. If they’re equipped with flood coolant, the mess is even worse.
With an Enclosure, the mess is kept inside and doesn’t get all over your workshop.
A 4th Axis installs on the CNC Milling Machine’s and adds another axis of motion.
They’re useful for a variety of things ranging from allowing more sides of parts to be machined in one setting to allowing more parts to be held on the table to allowing continuous rotary machining or engraving.