CNC Milling Machines: A Comprehensive Overview

 

What is a CNC Miller Machine

CNC miller machine, more commonly known as the CNC milling machine, is versatile machinery used for CNC milling. CNC milling is a machining process which utilizes computerized controls and rotating multi-point cutting tools to aggressively remove materials from the work object and product a custom-designed products.

CNC milling machine can be used for processing a wide range of materials, such as metal, glass, plastic and woods, all of which can become a variety of custom designed parts or products as a result.

CNC milling machine also offers a handful of capabilities including mechanical, chemical, electrical and thermal processes. It can be complemented with other mechanical processing such as drilling, turning, and a variety of other machining process. The material is removed from the work piece through mechanical means like the actions of the cutting tools of the milling machine.

In this article, we will provide you with a basic outlook outlining the machining process using a CNC milling machine.

 

CNC Miller Machine Working Process

CNC, or Computer Numerical Control, places tools and processes work pieces under the direct guidance of a computerized operating system. CNC milling is essentially a combination of three elements:

• A cutter with multiple teeth with certain sharpness for easy material processing.
• The capability to spin a tool at a speed high enough to process material correctly and precisely.
• An appropriate feed rate for advancing the intended material through the process.

 

CNC milling machines allow extremely close control and oversight of these elements. The computerized systems are able to read the design information directly from an engineer’s drawing, cross-referencing between the design and production to eliminate errors.

To illustrate deeper, the CNC milling machine takes from a project’s CAM or CAD designs, and convert them into directions using customized software codes, such as NC code, G-code, and ISO code. The codes are then translated into CNC machine’s controls, which run along two axes (X & Y) at least, in addition to the tool spindle running in the depth (or the Z axis). Some CNC milling machines will allow for controls on up to 5 unique axes.

 

Main Components of a CNC Miller Machine

In this section, we have broken down the core components that make up a fully functional CNC milling machine for you.

• Frame: The frame is the core structure that supports the CNC milling machine which provides stability. It is usually made up of a base and detachable columns. The headstock is an important part of the frame where the spindle is mounted. The headstock is however often overlooked.
• Spindle: Imagine spindle as the heart of a CNC milling machine. It is normally comprised of a rotating assembly and a tapered section where tool holders can be positioned. Tools are normally attached onto the shaft of the spindle through a tool holder.
• Axes: Generally speaking, a CNC milling machine has X,Y and Z, as well as extra rotational axes that are subject to configuration. All of these can be pre-programmed using G-code in the CNC controller.
• Columns: The columns of a CNC milling machine can either be single or double. This is based on the degree of complexity needed in the machining operations.
• CNC Control Panel: Think of this as the “nervous system” of the machine. It is designed with the needed electronic components to control various cutting actions through programming functions. The control panel has a CNC monitor and buttons where codes and data can be input by the users. Users also have the option of manual function. You’ll notice that the control panel is usually located at an easily accessible part of the machine for easy reach.
• Tools: Tools or tool changers are either mounted at the column or separately to the machine.
• Tools Holders: Tool holders come in various sizes, systems and applications. The sizes for tool holders are BT 30 to BT 40 and BT 50. For those who are unfamiliar, BT is referred to as the taper angle of the cone on the holder.
• Table: The table provides a solid surface which allows work pieces to be clamped onto. It can also be used to mount fixtures or vise to hold the work piece in place. Most of the tables for CNC machines use T-slots for easy clamping of vise, fixture or part.
• Coolant Tank: Most CNC milling machines have coolant tanks that prevent overheating during machining action as coolant is supplied to the cutting surface or the spindle. This is beneficial to the longevity of the machine by keeping temperatures under control.

 

Costs of CNC Milling Machines

The price of a CNC milling machine actually varies significantly. It is largely depended on what components you decide to build into the unit. Take the points below into consideration as each can affect the cost of your CNC milling machine:

• What is the intended application of your CNC milling machine?
• How many axes are to be involved? 3 axes or 5 axes?
• How large do you want the CNC milling machine to be?
• Do you need a pallet change? If so, manual or automatic?
• How powerful do you want the spindle to be? What is the revolution per minute needed?
• What is the degree of accuracy needed?
• What type of materials will be used for machining?
• What is the type and size of the computerized control systems needed?
• Is your intended production more custom or mass production oriented?

 

Ask yourself the above question in relation to your budget so that you will be able to make the best purchase decision. The matter of fact is that these machines can be as low as from USD$50,000 to several millions.