Whenever you see big heavy machinery in action, have you ever wondered how their components could be made? How come the parts just fit in the complex heavy machines so perfectly? You cannot imagine them being made in a furnace.
A complex machine cannot be made in a non-controlled environment, or, if I were being precise, it requires perfection to the finest to achieve the endurance and longevity of the parts. From production to the assembling part, a technology that is behind that feat playing is known as Precision CNC machining.
As the name suggests, it is meant to be fully accurate to mass produce the complex machining components. Keep reading as we explore this massive feat of the industrial era right here.
A step-by-step guide to precision CNC machining
Picture any product in your mind. It could be a car, a rocket, or a toy that is engineered precisely to function. Each of them is precisely engineered to provide the best performance possible. But what steps are going behind to make all that happen? You should know the backend mechanism as it will help you understand how precision CNC machining makes the perfect outcome feasible.
Precision machining requires highly detailed blueprints generated by Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) programs. A CNC machine can create a 3D outline for a machine, tool, or object that can be manufactured. To ensure the quality of a product, blueprints need to be created in great detail.
In the initial stages of precision machining, many companies work with hand-drawn sketches rather than CAD/CAM programs.
Advantages Of High Precision Machining
Precision and repeatability are key factors to achieve high-quality and cost-effective machining. But, CNC precision machining helps meet performance and quality requirements in several ways. That brings us to its superior advantages:
1. A high level of machining technology
With CNC machining, we stay true to industry 4.0 standards as it complies comfortably with the latest technology. Due to this, heavy machinery is easily and effectively operated, and labor is reduced.
Today, almost all CNC machine tools can be automated using computer programs. The operators manipulate cutting tools and shape raw materials into desired products using different cutting tools.
2. Enhances performance and reliability
The results of traditional machining can be acceptable for some applications, but others require very tight tolerances. Machining these parts with high precision is necessary due to their specific requirements/industrial standards.
It is also common for most industries to require many similar parts. Precision CNC machining is the only solution allowing this repeatability level. CNC machines apply similar cuts to all parts, ensuring equal quality at all times.
3. Applicability ranges from the very basic to the very advanced
A precision machining process is compatible with a wide range of materials, including metals and plastics of high quality. It helps companies of all sizes compete in the market and offer customized products.
Additionally, a consistently tight engineering tolerance can establish customer confidence. Precision CNC machining is useful in many industries, such as automotive, metalworking, aerospace, marine, agriculture, and consumer goods.
4. A reliable quality assurance system
CNC machines are unmatched in precision machining. With a computer numerical control, there are no variation problems.
You don’t have to worry about maintenance or software; it can run smoothly for hours. The resulting high quality, exceeding customer standards, can be achieved even with the most complex parts by utilizing advanced processes.
5. Cut down on cycle times and labor costs.
CNC precision machining can handle higher production demands thanks to enhanced machining automation and programming abilities. They’re designed to be highly accurate and repeatable.
On the other hand, conventional machining requires manual tooling adjustments and tuning. Conversely, a CNC machine can run offline programs. One machine operator can easily change over machining centers and run different production lines. Besides deburring and quality control offline, the operator maintains parts and tooling.
Thus, the structure requires very few operators for monitoring, reducing labor costs. It also ensures that components are created more quickly, regardless of their quantity.
Precision CNC machining equipment types
Each process requires a different piece of equipment because it’s different. These tools are sometimes assembled on a single precision CNC machine, and the machinist must only start and stop the machine. Sometimes, the tools must be placed on different machines, and the machinist must move the workpiece or raw material around. Below are some of the most used precision machines that you’ll encounter in most industries:
CNC Milling Equipment
Milling involves removing excess material with rotary cutters. There are several types of mills involved. Examples of this type of mill include end mills, chamfer mills, and helical mills.
Besides CNC-enabled mills, we have hand milling machines, plain milling machines, universal milling machines, and universal milling machines. Depending on how they’re oriented, they’re either horizontal or vertical.
Drilling equipment using CNC technology
The drilling process creates cylindrical holes in raw materials/workpieces using rotating multi-point drill bits. As a bonus, the drill bit design allows chips from the workpiece to fall away from it, which keeps the hole neat.
Drill bits that are commonly used in CNC machining include spotting drills for shallow or pilot holes, peck drills for reducing chips on the workpiece, screw machine drills for making precision holes, and chucking reamers to enlarge already-made holes. There are also drill presses, which are drill bits for specific drilling jobs.
Electric discharge mining equipment controlled by CNC
Electrical discharge mining uses electrical discharges to produce parts with precision CNC. In this setup, an electrical voltage is applied to the workpiece and tool electrodes. Spark machining, spark erosion, burning, die sinking, and wire erosion are all words that describe the process.
How to Carry Out Precision Machining
The total point of shifting this technology is achieving perfection, peace of mind, and generating a high mass production with a seamless process. Speaking of all these factors, running this technology in your industry is pretty flowing, consisting of three steps:
1. Programming
2. Processing
3. Optimum Surface finishing
1. Programming
The machines need to be programmed to make the precise machining process run smoothly without errors. I’ll walk you through the process:
First, your design goes through CAD software that makes your product’s 2-dimension vector or 3D solid blueprint. Then in the next step, it is exported to a CNC-compatible file format like STEP or IGES.
After that, the CAM generates the digital programming code that controls the tooling.
There are two types of codes: G-code and M-code. G-code stands for Geometric code and is more popular. It instructs the machine when, where, and how to move. An M-code controls auxiliary features of the machine.
2. Processing
To make the finished product match the exact specifications, it needs to be processed to fit the exact specifications of the machine. Many CNC processes are involved in making the final product, depending on the product. A couple of examples are:
a. CNC Milling
b. CNC Turning
c. CNC Drilling
3. Optimum surface finish
In this process, the surface of the finished product is plated with different materials to make it stronger and nicer. Hence, this process is a testament that the final finish of the product is ready.
Accuracy vs. Precision: What’s the difference?
Precision describes the ability of a measurement system to consistently return the same measurement, whereas accuracy describes how close a measurement is to the true value.
Think of hitting the bullseye on a target practice chart to understand the difference between these terms. Accuracy is how close your shot is to a given target. Say you hit the x-point with your first shot. You’d get 9 out of 10 points, meaning you hit it 90% of the time.
You decide to give it another try after your 90% accuracy, as it didn’t please you. Nevertheless, you did worse this time when you consecutively hit the same point. So, we could say that you were less accurate, but you were more precise. You can think of precision as the repeatability of your measurement system.
Imagine you’re trying to cut a very accurate hole in a metal piece. This metal piece will be cut exactly to your specifications and without errors using CNC machining tools. This same cut can be made for 100 units of the workpiece by a highly precise (or repeatable) CNC machine unless a mechanist has an error while generating the code for a product.
Conclusion
CNC precision machining is a great way to make custom precision parts. You also save money and get your products to market faster with it. As it can create complex and tight tolerance parts efficiently and cost-effectively, it is no wonder that precision CNC machining continues to be a mainstay in many industrial standard manufacturing operations.
