How are threaded spindles actually manufactured?

There are those who simply accept the existence of certain components without questioning their origins. On the other hand, there are individuals like you—curious souls eager to understand the intricate details behind things. So, where do you fall in this spectrum? Judging by your interest in reading this article, we’re betting on the latter. Today, we’ll explore the fascinating process of how threaded spindles are manufactured.

When it comes to creating external threads on bolts, most people might instinctively think of using a die. While this works for shorter components, threaded spindles are typically much longer. Attempting to use a die for such lengths would either prove impractical or incredibly time-consuming. Therefore, other techniques must be employed to craft these essential components. What machinery can handle such oversized parts? And what are the pros and cons of the various methods used to produce threaded spindles? Let’s dive into the details!

What Are Threaded Spindles Used For?

Before diving into the manufacturing process, let’s clarify what a threaded spindle actually is. Fundamentally, it’s a long rod with a continuous thread along its entire length. Unlike regular threaded rods, however, a threaded spindle is unique because its thread serves as a functional moving component. These spindles are indispensable in machinery across industries, enabling movement through rotation. The spindle turns on its axis, driving the spindle nut back and forth via the thread. There are two primary methods for producing these specialized components: thread rolling and thread whirling.

Manufacturing Threaded Spindles Through Thread Rolling

Thread rolling, sometimes referred to as thread whirling, is a widely adopted method for creating threaded spindles. Here, the blank is pushed between two rotating rollers, each engraved with the desired thread profile. This compresses the material rather than cutting it, resulting in a chipless process. Instead of severing the material fibers, this method simply presses them into place. Thread rolling can produce spindles of almost any length, provided the material is suitable for cold forming and the thread profile isn’t overly complex. However, since it’s a non-cutting process, it generates significant frictional forces, requiring proper lubrication and cooling throughout the procedure.

Manufacturing Threaded Spindles Using Thread Whirling

For thread whirling, a specialized tool called a whirling ring is used. This ring is lined with sharp indexable inserts on the inside. The process resembles thread milling, where the blank moves through the ring while spinning rapidly. The sharp inserts carve the thread directly into the bar, making it a cutting process. This method offers versatility in terms of thread types and materials, making it a go-to choice for various applications.

Comparing the Two Methods for Producing Threaded Spindles

These two approaches differ significantly in several aspects, and their outcomes reflect those distinctions. Three key factors stand out:

Chipless vs. Cutting Processes

The primary difference lies in whether the process is chipless (as in thread rolling) or cutting (as in thread whirling). In chipless production, no material is removed, meaning no chips are produced, and the material fibers remain intact. Threaded spindles made this way boast a superior surface finish and are less prone to wear. Additionally, the absence of chips eliminates common chip-related issues and reduces post-production cleaning efforts.

Efficiency in Production

Another advantage of the chipless thread rolling process is reduced material usage, especially beneficial in mass production. While this doesn’t apply to small-scale projects, thread rolling excels in speed, allowing for rapid production of large quantities of threaded spindles.

Flexibility in Customization

In contrast, thread whirling offers unparalleled precision and adaptability. This makes it ideal for producing custom designs and working with diverse materials. The flexibility of whirling rings allows them to handle special geometries, making thread whirling the preferred choice when thread rolling reaches its limitations.

Which Method Is Best for Producing Threaded Spindles?

Based on the differences outlined above, it’s clear that thread rolling is best suited for standard, high-volume applications. It provides quick, reliable results, ensuring both efficiency and excellent surface quality, which extends the spindle’s lifespan. However, there are instances where thread rolling can’t meet specific requirements due to material constraints or complex thread designs. In such cases, thread whirling steps in to deliver precise, tailored results.

Can You Make Threaded Spindles Yourself?

If you’re tempted to try making a threaded spindle at home, you’ll soon realize it’s not a task for amateurs. Producing threaded spindles requires large machinery and specialized tools. For personal projects, it’s far easier—and safer—to work with pre-made components. For simpler tasks involving external threads, a traditional tap usually suffices.

Looking for top-quality threading tools like dies, taps, and more? Check out our online store at BAER. Our customer service team is always available to address your queries and help you select the right tools for your needs.