Tapping is another way to create threads but mainly inside a hole. It involves using a tool called a “tap,” which basically looks like your average screw with grooves, and it works almost like a standard drill. The tap is turned into a hole, and it cuts threads as it goes. It’s a fairly straightforward process that can either be done by hand or with a machine and can be used to make threads in aluminum or steel.Â

However, if you want to make different hole sizes with tapping, you’ll need many tools on hand. Also, once the thread is cut, it’s hard to change its size. Tapping is also not suitable for making external threads, although it’s great for internal ones.Â

If you’re stuck between choosing thread milling or tapping for your manufacturing needs, the table below should help you out of your pickle.

A tap looks kind of like a screw or bolt and has groves with sharp edges all the way down its sides that remove the chips from metal to make threads. They’re held in place by a collet, chuck, or other type of tool holder and then moved toward the material. Here’s an example of what a tap looks like.

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Thread milling is a manufacturing technique used to create threads. Instead of using a standard tool (like a tap), thread milling uses a specialized cutting tool designed for just this purpose called a thread mill. This mill is guided by a CNC machine for precise control, and its key feature is that, to make a thread, it moves the tool sideways in a circular pattern and carves it out in just one full turn.Â

Tapping is a speedy process, especially if you��’re looking to make lots of threads in a short amount of time. It can make deep threads in tough materials like steel and is the way to go if you need to make very small threads.

In the table below, you’ll find a more analytical explanation of their exact differences in all the important categories.

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With thread milling, you have very accurate control over the size and fit of the threads you want to make. A single tool can make all different sizes and types of threads, even in tough materials like titanium or stainless steel, and it can make custom threads without you needing to splash out on custom taps. You also won’t need another tool to adjust the thread’s size if need be. It offers a high level of accuracy, and can make both interior and exterior threads, and both right- and left-handed ones.

Thread mills are usually made from carbide which can last through thousands of holes before needing replacement, something that can be further extended when it’s kept clean and properly maintained. A thread mill looks a bit like an end mill but with a special thread pattern on the sides. There’s a shank for easy mounting on a tool holder, lots of teeth for cutting threads, and protective coatings to help them last longer. Below is a picture so you can get an idea of what a thread mill looks like.

Basically, if you need to make a lot of threads quickly, particularly small or deep ones, go for tapping, which is usually faster. It’s also more economical if you only need to make a few threads in standard sizes – so it’s good if you’re on a tight budget. If you need to adjust thread sizes, and work with various materials, large or custom threads, thread milling will be the method for you. It’s adaptable, and the tools also last much longer.

On the flip side, thread milling requires quite specialized machinery with a high spindle speed (up to 60,000 RPM), and this could be quite the investment. Also, for very tiny threads (like those you’d find in watches or some medical devices), thread milling might not be the best option—the tools and process just aren’t ideal for the superfine precision needed for those tiny threads.

This is just an example as their appearance will vary on their size, length, and design — and there’s a whole bunch to choose from.Â

In tapping, a hole that's just the right size for the tap is drilled — it needs to be big enough for the tap to fit but small enough to make room for cutting the threads. After drilling, the tap is lined up with the hole, and some lubricant is added to help reduce friction and heat. Then, the tap is carefully turned into the hole, cutting the threads as it goes. The direction has to sometimes be reversed to clear out the chips created. Once the threads are cut, you’ll need to clean up any leftover chips or lubricant.

Thread milling and tapping are two methods of making threads in metal; those spiral grooves inside or outside of a hole that screws are meant to fit into. They’re both popular milling processes in the manufacturing industry, but they are very different. Let’s take a look at these two threading processes, the differences between them, their pros and cons, and when each should be used.

This means that it can make threads with very precise spacing (thread pitch) — perfect if you need various sizes and completely customized threads to fit specific needs, without having to buy pricey rigid taps. For example, a 16-pitch thread mill can cut any 16-pitch thread, and you can easily switch to other sizes or pitches with the same tool, just by changing the machine’s program.

If you’ve decided which thread-making method is right for you, or if you are still stuck and want some help in the matter, our experts are on hand to help you out. Reach out to one of our reps or get a free, no-obligation quote for any of your manufacturing needs.