Most shops need to create female or internal threads in some workpieces. Years ago, they used manual methods with taps and dies to create threads, and they worked well. However, thanks to modern machinery, you can use one of the several automated methods. Many shops use tools like Emuge taps but they also have the choice of threading with a milling machine and this process is called thread milling. The truth is, today’s machine shops often use both methods but they are not interchangeable. Here is information to help you choose the best threading method for each job.
What is Thread Tapping?
The process of thread tapping is easy to understand. For example, if you cut a hole in a piece of metal or wood and insert a threaded tool (slightly larger in diameter) into the hole, all you have to do is turn the tool, and it will cut threads inside the hole. This method is centuries old and very effective.
Thread Milling
Instead of using tools like Emuge taps, you can use thread mills. These tools are special thread-making tools designed for milling machines. A milling cutter creates many shapes by moving laterally (as opposed to the up and down motion of a drill bit or thread tap. A thread mill is smaller than the hole it threads and once inserted; it cuts the threads into the hole by moving in a circular motion inside the hole.
Which is Best?
When you use high-speed tools like Emuge taps, you can thread faster and deeper than a thread mill tool. The process is good for making many threaded holes of the same size.
If you use tools like Emuge thread mills, you don’t need to change tools for each size. Thread milling can produce precision threads to a high tolerance. Also, the same tool can create both internal and external threads.