An Ultimate Guide to Understanding A CNC Fixture

CNC machining encompasses a variety of tools used in different capabilities. Without proper understanding, it can be hard to understand using the tools. An example of such tools is the CNC fixture, also known as CNC work holding fixtures.   

This article will demystify CNC work holding fixtures in three steps. It will show their functions and applications. It will give solid information on the types of CNC work holding fixtures. Finally, it will give you premium information on what to do to get the best CNC fixture design or use a custom CNC fixture.

What Is A CNC Fixture?

The best definition to give a CNC fixture is that it is an agent of stability and positioning. It is a work-holding device with wide uses centered on securing, supporting, or mounting a workpiece correctly on the CNC machine.

CNC fixture is an important tool that ensures conformity and interchangeability during the machining process. In other words, it encourages a smooth manufacturing operation.

You can also say CNC work holding fixtures reduce the amount of effort human exerts in a manufacturing process. With this, many will compare them to jigs. However, they are different. A jig works to guide the cutter’s movement. However, CNC workholding fixtures do not guide cutters. They only secure, support, and stabilize the workpiece during the manufacturing process.

Also, with CNC work holding fixtures, the tool moves when the workpiece moves. With jigs, the tool is always stationary.

Applications of CNC Fixture

CNC fixture has wide applications in the manufacturing industry wherever CNC machining is employed. Its functions are integrated with the types of CNC operations used in the manufacturing process.

It is used in CNC milling, CNC turning, CNC planning, CNC slotting, and CNC grinding. This will also lead to the types of CNC fixtures which we demystified below. 

Generally, the CNC fixture design is responsible for its application:

• Positioning

CNC work holding fixtures make sure the workpiece is fixed correctly on the machine relative to the machine tools. This is also to make sure that the machine surfaces meet the requirements.

• Clamping

After positioning, a CNC fixture applies a force on the workpiece to grip it firmly during any manufacturing process.   

CNC work holding fixtures use these two properties in their functions. For example, positioning and clamping play a major production role in the automotive industry. There, they secure and guide vehicles through the welding and assembly process.

Types of CNC Fixture

Classification of CNC work holding fixtures is something most people familiar with the tool don’t get. Yes, it is not that straightforward. Since it is not straightforward, it is frustrating for beginners to understand the tool and the idea. However, with this ultimate guide, you have nothing to fear. This section will introduce you to the types of CNC fixtures from a different point of view.

Based on the CNC Machining Operations

When classifying based on CNC operations, there are five types of CNC fixtures. Below is a little introduction to the CNC fixtures.  

• Turning Fixtures

CNC turning is a CNC machining operation in which parts of a workpiece are removed while rotating on a single axis. Turning fixtures are CNC fixtures that are used during this process.

• Milling Fixtures

CNC milling is simply a cutting CNC machining process. In this process, the computer directs the cutter to cut the required part of the workpiece away. Milling fixtures are CNC fixtures used in this process.

• Drilling Fixtures

Drilling is a popular process in the manufacturing process, and it is more popular in CNC machining. It simply means making a hole in a workpiece. CNC fixtures used in CNC drilling are called CNC drilling fixtures.

• Boring Fixtures

CNC boring is a CNC machining process in which a tool is used to enlarge holes already drilled using CNC drilling. The fixtures used in this process are CNC boring fixtures.

• Grinding Fixtures

CNC Grinding involves removing a  part of a workpiece with the aid of a Grinder. It is another popular CNC machining process used in cutting aside CNC milling. Grinding fixtures are fixtures applicable in CNC grinding processes.

Generally, you can reach a valuable conclusion on CNC fixtures based on CNC machining operations. Every CNC machining operation that requires the need for a fixture has the name of the operation. Therefore, you can have others such as CNC honing fixtures and CNC lapping fixtures.

Based on their Uses

You can categorize CNC work holding fixtures based on their uses. CNC fixtures under this category are of five types. Below is a little introduction on the five.

• Universal Fixtures

Universal CNC fixtures are usable on any workpiece with ease in adjusting them. Each part of the fixture is adjustable and replaceable to suit any workpiece. Like its name, universal fixtures have a very wide scope and applications.

• Special Fixtures

A special fixture is a CNC fixture ideal for a particular workpiece. When used with this particular workpiece, they offer a load of advantages in terms of stability. There is also a quicker operation and convenience during use.

• Assembled Fixtures

An assembled CNC fixtures can only arise after considering a workpiece. The fixtures are according to the requirement of such workpiece. The assembling is via a special method. Depending on the need you can remove or reuse them when necessary.  

• Modular Fixtures

A modular fixture is easy to reconstruct and reconfigure to fit any workpiece. They come from interchangeable components and are ideal for handling many workpieces. You can also dismantle the fixture after concluding the process. Modular fixtures give a better and more flexible manufacturing process.

• Combination Fixtures

Combination fixtures come in different sizes and shapes. They are ideal for handling many workpieces of different sizes and shapes based on the machine tools.

Based on their Power Source

This is the last classification process and is based on the power source of the CNC fixture. Below are the six types of CNC fixtures based on the power source.

• Manual fixture.
• Pneumatic fixture.
• Hydraulic fixture.
• Electric fixture.
• Magnetic fixture.
• Vacuum fixture.

What to Know When You Want to Design or Use CNC Fixture

Using the CNC fixture or getting to know the right CNC fixture design comes with understanding many things. Below are some things to know whether you already have a cnc fixture plat or you need a custom CNC fixture.

• Improves the Tolerance Level

CNC workholding fixtures contribute to your manufacturing operation’s tolerance. Therefore, it is important to make sure its setting improves accuracy.

• Know When You Should Clamp

The way you clamp has a huge effect on the quality of the products. While you might think the best thing to do is to clamp well to secure the workpiece, do not.

• Reference Important Surfaces

You might need to reference important workpieces on the tool if you value lesser operational time. However, you should not reference many surfaces to avoid confusion.

• Be Economical

Another important thing to note while designing a custom CNC fixture is being economical. You need to know the number of parts you are making and the number of fixtures you need.

Get Your Custom CNC Fixture at Rapid Direct

Using CNC machining comes with understanding the operations and tools involved. In terms of getting CNC fixture design or a simple custom CNC fixture, you are guaranteed the best at Rapid Direct.

We are a manufacturing company with the right background, vision, and capability to deliver the best. It is this we focus on when making or designing CNC fixtures for our customers.

We have (ISO 9001:2015) certification, which shows how much we care about our customer’s wants. Our institution has qualified engineers with reputable educational backgrounds and experience to answer and give you suggestions. In short, with us, you get to enjoy the best CNC fixture design or anything related to CNC machining at a low price.

Conclusion

CNC fixtures are an important tool with a shroud of mystery around. However, this article demystified the tool in terms of its types and functions. After going through it, you will understand the process and the little things you need for a smoother operation, in between when you think of smooth operation and high quality at a low price, think Rapid Direct.