Milling Machines: What Are They Used For?

Milling Machines: What Are They Used For?

Milling is a machine-based operation in which the cutters rotate to extract material from the workpiece in the direction of the tool axis. From small items to big ones, the milling machine can perform a wide range of operations and functions.

In this article, we are going to outline the different parts and types of a milling machine to better understand its function and uses.

Milling Machine, Defined

Milling machines are widely used to mill materials with irregular and flat surfaces including solid materials such as metal, plastic, and wood. In contrast to a lathe, where the component rotates during the cutting process, the cutter is designed to rotate during the operation.

Self-contained electric drive motors, coolant systems, digital readouts, variable spindle speeds, and power-operated table feeds are all standard features of milling machines. They can be used to drill, bore, cut gears, and make slots and pockets, among other things.

Milling machines are often referred to as multi-tasking machines (MTMs) since they are multi-purpose machines that can mill and turn materials. The milling machine is equipped with a cutter, which aids in the removal of material from the workpiece’s surface.

Parts of a Milling Machine

Milling machining is a popular manufacturing method used in machine shops and industries to produce high-precision items. It comes with many parts, starting with:

1. Column and Base

One part of the milling machine’s foundation is the column. On the base, it is a mountain that rises vertically. It provides support for the knee, table, and other objects. Work serves as a home for all other drivers. It is a hollow member for the axle and table that contains a driving gear and, in some cases, a motor. The axles are lubricated by an oil reservoir and pump in the column.

2. Knee

The milling machine’s knee is the first moving component. Casting is supported by the saddle and table. The gearing mechanism is built into the knee. Dowell’s methods secure the knee to the post.

A vertical positioning screw, also known as an elevating screw, keeps it in place and improves it. By pushing the lever up and down with the aid of a hand or power feed, the elevating screw will adjust the knee up and down.

3. Saddle and Swivel Table

The table is supported by the saddle, which is at the knee. The saddle rides on the knee’s horizontal dovetail, which runs parallel to the axis. The saddle is equipped with a swivel table that rotates horizontally in both directions.

4. Power Feed mechanism

The knee is where the power feed mechanism is located. The longitudinal, transverse, and vertical feeds are all regulated by the power feed mechanism. The feed selection lever is placed to point at the feed selection plates.

Feed is obtained by turning on the speed selection handle until the rate of feed selection is shown on the dial of the column milling machine and universal knee.

A quick-moving lever is found on almost every milling machine and is used when a temporary increase in longitudinal, transverse, or vertical feed speed is needed. When the operator is organising or placing the machine, this lever is used.

5. Table

The table is a rectangular casting that can be found at the saddle’s tip. A task or task-holding instruments are placed on the table. There are many T-slots to keep the job and equipment organised. It can be done by hand or by computer.

Turn and rotate the longitudinal arm crank to shift the table by hand. It feeds the control lever with power and longitudinal direction to control gait.

6. Spindle

It sits between the table and the knee and serves as a transition between the two. On the forehead, this column can travel transversely. It slides on guideways that are perpendicular to the face of the column and are centred at the knee. Its primary purpose is to shift the workpiece horizontally. It’s made of cast iron as well.

7. Over Arm/Overhanging Arm

It is an overhang on the column’s surface that supports the arbour on the other end. It may be a single dowel-style casting and slip at the top of the column. On a horizontal milling unit, it’s above the column. It is made of cast iron.

8. Arbour Support

The arbour support is made of cast iron and has a bearing that supports the arbour’s outer end. It also aids in aligning the arbour’s outer end with the axle. Arbour protection prevents the outer end of the arbour from springing during a cutting process.

In milling machines, two types of arbour support are commonly used. The first has a bearing hole with a full diameter of 1 inch and a small diameter. The second has a hole with a wide diameter of up to 23/4 inch.

9. Ram

In a vertical milling machine, rams act as the overhanging arm. The milling head is attached to one end of the ram, which is mounted on top of the pillar. The arm is fixed to the pillar on one end and the milling head on the other.

Types of Milling Machines

To have a clear idea of which machine suits your needs and requirements, take a look at the different types of milling machines below: 

Horizontal or Plain Milling Machine

Hand millers are less durable than plain milling machines. Horizontal milling machines are simply plain milling machines with horizontal spindle. The table may be fed vertically, crosswise, or horizontally.

Horizontal milling machines, in other words, place the cutting tool on a horizontally oriented spindle that can selectively extract material from a stationary workpiece. They typically have different cutting tools than vertical milling machines.

These machines feature a similar design in which a spindle containing a rotating cutting tool presses against a workpiece to remove material from the workpiece. Having said that, horizontal milling machines vary from their vertical counterparts in many ways.

The direction of the spindle is the most significant difference between these two styles of milling machines. The spindle on vertical milling machines has a vertical orientation. The spindle on horizontal milling machines has a horizontal orientation; the verticle adjusts the table vertically; the cross aligns the table with the spindle, and the longitudinal rotates the table

Vertical Milling Machine

On a vertical milling machine, the spindle is either perpendicular or vertical to the table. This system can be used to make holes, grooves, and flat surfaces. The spindle head is mounted on a vertical column that rotates at a 45-degree angle. To deal with angular surfaces, the milling cutter is mounted on the spindle. The spindle of some vertical milling machines can be moved up and down.

A vertical milling machine is a precision tool that shapes and fabricates metallic workpieces by removing stock. The machine can also mill plastics and other materials, depending on the tooling and content.

Manually operated, CNC-controlled, or a combination of both mill controls are available. A rotary cutter held in a spindle is commonly used for mill machining and material removal.

Because of the moveable table and/or vice (x and y-axes) and vertical spindle movement, cutting options are more sophisticated and variable than on a drill press (z-axis). Many vertical mills feature a rotatable turret for the upper cutting head. This is ideal for even further machining possibilities (b-axis).

Universal Milling Machine

A universal milling machine has a table with all motions and a dividing head with change gears that allows it to perform any sort of milling operation.

It can adapt to a wide variety of tasks. From its usual location, the table will rotate at any angle for up to 45 degrees on both sides. The horizontal milling machine’s table can move in three directions, and it also has the fourth movement. Helical milling operations are also possible with this unit.

Additional attachments may be used to increase the machine’s size. Slotting, rotary vertical milling, and an index head or dividing head are examples of special attachments. This machine can make milling cutters, reamers, twist drills, spirals, bevels, spurs, and much more. The universal milling machine can perform all of the operations that a shaper machine can.

Simplex Milling Machine

Only one direction can be travelled by the spindle or spindle head of a simplex milling machine. Stable milling, excellent surface finish and flatness of milled surfaces, high tool life, high efficiency, and low maintenance are all features of these milling machines.

Duplex Milling Machine

Duplex milling machines are two machines positioned one opposite the other. They can work independently or as a single milling machine. The spindle can move horizontally as well as vertically.

The following are the key benefits of a duplex milling machine:

  • Unlike traditional solutions, such as individual milling machines, production can increase by up to 50% with duplex milling machines.
  • There are improvements in accuracy. This is a result of being able to machine the part in a single setup in the majority of cases.
  • The duplex milling machines can be controlled by a single operator.
  • When compared to two single machines, there is less room and money required.
  • Due to high productivity, investment amortisation is fast.
  • The duplex solution can be configured in a variety of ways, including a single work area, pendulum work areas, or a pallet changing device.

Triplex Milling Machine

The spindle will move in three directions: left, right, and up and down. Axis X, Y, and Z. It has a special implementation focused on the customer’s accuracies criteria. It is also highly efficient and precise.

Rotary Table Milling Machine

The ability to conduct 2D and 2.5D machining cycles on or on the end of a cylinder is known as rotary milling. The tool can only move parallel to and around the rotary axis while radial machining (machining around the cylinder). The method is always directed radially to the rotary axis’s centreline.

A circular table rotates in a vertical axis on the rotary table milling unit. Multiple cutters must be placed at various heights. The machine works by roughing up the workpiece with one cutter and completing it with the rest of the cutters. The most important benefit of the rotary table milling machine is that the operator can load and unload workpieces continuously while the machine is running.

Tracer Controlled Milling Machine

Via tracer modulation, tracer-controlled milling machines are equipped with copying capabilities, allowing them to replicate or duplicate external or internal geometries in two dimensions. Cams, grooves, contoured surfaces, and other items are machined with tracer operated milling machines.

This machine is ideal for tracing elements and replicating complex and irregularly shaped components. The stylus activates the oil relay mechanism, which controls the table’s primary hydraulic system. The term for this form of arrangement is servomechanism, and it is very complicated.

Cams, grooves, contoured surfaces, and other items are machined with tracer operated milling machines. Three-dimensional profilers or duplicators may be used for die-sinking and other cavity machining processes.

CNC Milling Machine

CNC milling, also known as computer numerical control milling, is a machining technique that uses computerised controls and rotating multipoint cutting tools to extract material from a workpiece to create a custom-designed component or product.

A CNC Milling Machine transforms the material into a vehicle or mechanical component by moving a rotating cylindrical cutter along multiple axes and creating slots, gaps, and details. The majority of machines have three to five axes, allowing for greater precision and detail.

Both horizontal and vertical machining centres are built into modern CNC milling machines. Plastics, ceramics, and composite materials, in addition to metals, can be used to make components.

Automatic tool changers, tool carousels & magazines, coolant systems, and enclosures are among the technical features that keep machines working smoothly without the need for human intervention.

Drum Milling Machine

Only manufacturing work is done with drum milling machines. Like a Ferris wheel, this unit has a vertical central drum that rotates on a horizontal axis. Face mill cutters are used, and roughing and finishing cutters similar to those used on a rotary-table miller are often used.

The drum fixture rotates slowly in action, carrying the job toward spinning cutters. There are typically four cutter spindles. Since machined parts are removed and new ones are inserted after the work cycle is finished, the process is continuous. This machine mills cylinder heads and small shafts for automobiles.

Wrapping Up

As a leading machine for cutting metal, milling machines are commonly used for producing parts within the automotive and aerospace industries.

While milling machines come in a variety of shapes and sizes, their primary function remains the same. Regardless, using the right computer for the job is critical. We hope that this guide has given you a better understanding of milling machines.

If you are looking for milling machines, consider our products at Accurate Cutting Services. As part of our quality services, our team will help you figure out which ones suit you best. Get in touch with us today to learn more about our services.