What is Precision Machining?

Precision machining is used worldwide to manufacture millions of parts and components. Machining plays a significant role in the manufacturing industry.

Precision machining is a manufacturing process that uses cutting tools to remove material to form a component. To be considered precision, the tolerances are usually ± 0.005 inches — about the diameter of a human hair. Some machines can reach a ±0.0001 inch tolerance.

Maintaining tight tolerances is essential for many industries. Precision parts are used in vehicles, industrial products, electronics, and aerospace equipment. This article will give you an overview of the precision machining tools and processes.

Precision machining methods

There are many different manufacturing processes and tools used to create specific parts. Some part designs require different cutting tools and techniques.

CNC machining

CNC machining is the most common precision machining technology. CNC stands for computer numerical control. That means that the machinist enters the part specifications into a computer program and the machine automatically makes the necessary cuts to form the part.

This process can take a while to set up —a new part can take up to 40 man hours before it’s ready to run. After that, the machine can run without much human interaction. This makes the production process very efficient, and helps reduce manufacturing costs.

CNC mills and CNC lathes are the most common types of machines. These machines can cut various features into the raw material. They can cut specific angles, drill holes, and add threading.

CNC lathes rotate the part material while a fixed cutting tool is moved around the spinning material to cut the raw material. CNC milling machines use a rotating cutting tool to form the part features, while the raw material is held stationary.

Precision CNC machining is used to machine parts for a variety of industries. Because the process becomes more efficient over time, CNC machining is best for larger quantities of parts.

Swiss screw machining

Swiss screw machining is a process that uses automatic lathes to machine parts. Swiss screw machining is used to produce large quantities of precision parts.

The process was originally designed to make parts for Swiss watches in the late 1800s. The name can be deceiving because the machines aren’t commonly used to make screws.

The Swiss-style machines became more advanced and efficient in the 1960s, and are used worldwide to produce millions of parts every month.

Similar to CNC machines, these can run 24/7 without much human assistance. That makes them very efficient for larger orders of parts.

The differences between traditional CNC machines and Swiss screw machines are subtle. A piece in the machine called the Swiss guide bushing prevents the bar stock from wobbling as it’s machined. This makes Swiss machines more suitable for smaller parts, and long skinny parts.

Multi-axis machining

Multi-axis machining is a process where the cutting tools move in 4 or more directions.

These machines can have 4, 5, 6, or even 12 different axes of movement. Some CNC lathes only work on one axis of movement, which would be used to machine cylindrical parts. Each axis of movement either moves the part along the X, Y, or Z axis, or moves the cutting tool.

For example, a 5-axis machine moves the part in 3 directions, and the cutting tool in 2 directions.

The complexity of these machines enables them to machine complex parts in less time. Previously, a machinist would need to stop the machine and turn the part into a new position to machine different features.

Because these are more complex, they take longer to set up. These machines are often used in the automotive, aerospace, and manufacturing industries where complex precision parts need to be machined.

Precision machining applications

What industries benefit from precision machining?

Today, more and more industries are taking advantage of precision machining.

Reduced development time, improved supply chain management, and higher quality products are just a few of the benefits. Customers of precision machine shops enjoy significant cost savings, improved efficiency, and increased profits.

If you look around, there are precision machined parts everywhere.

They’re in your car, your air conditioner, at your doctor’s office, and much more. Many things in the modern world require high precision parts to function properly.

The different types of precision machining equipment and techniques are used to make different parts. Some machines are used to make tiny parts, and others can be used to machine engine blocks.

The industries that benefit most from precision machining use large quantities of precision metal parts. Plastic parts are machined as well, but metal is the most common material.

Vehicles use a ton of different precision parts. Airplanes, cars, trucks, and construction equipment all rely on precision machined parts.

The aerospace industry uses CNC machining to make aluminum parts for planes and equipment. Oftentimes, these parts need to be within a 0.0001” tolerance. Precision machining provides the best solution for making everything from high tolerance spacers to complex bearing housings.

Precision machining is also used in the medical industry.

In this case, the need for precision could mean life or death. The parts and components need to be exact and perform as designed. Speed and repeatability is also necessary. Many machine shops transitioned to creating medical parts in 2020 when ventilators and other equipment was needed as quickly as possible.

Precision machining technology allows parts to be easily tracked, and the accuracy can be monitored with ease.

On the consumer side, precision machining is used to make prototypes.

CNC machines and multi-axis machines can form just about any shaped part in a short amount of time. And it’s easy to make small adjustments.

During new product development, CAD software and modeling give companies the opportunity to correct design flaws by producing a usable prototype that can be checked and approved before production begins.

Modifications and updates to existing products are also easy to implement, and offer short lead times for customers.

Spex is a precision machine shop that was founded in 1946. We are an ISO 9001:2015 certified company. Organizations use this standard to demonstrate the ability to consistently provide products and services that meet customer and regulatory requirements.

We incorporate world-class excellence in every step of the supply chain process: planning, manufacturing, quality control, and delivery.

Reach out to our team if you’re looking for precision machining services.