Metal Cutting Solutions Inc.

Tapping, thread milling, or thread forming is mostly used to create threads in metal parts. All these processes start with a rotating tool. For low volume applications, manual tapping by hand is used, but for larger diameter threads or higher production quantities, this is not economical and requires the help of machine tools. The process calls for automation by using either floor or bench mounted radial drills, or special tapping machines, or CNC or other programmable machine tools. To make the process reliable, tapping fluids are added, to improve the reliablity and to reduce the overall torque needed for the cut. However a tap will break when the maximum torque it can handle is exceeded. This can occur because of tool wear, insufficient lubrication, material defects, or when cutting chips are getting into the cut.  Cuttting chips are also often the cause for oversized threads. This makes tapping a most un-reliable automated cutting process.  In addition, when taps break, and this often un-expected, it stops the machines. Besides interrupting the production process, the extraction of the remaining tool sections creates a lot of ineffective work or is causes scrap parts. Especially for an automated process, this reduces the economics greatly. To overcome this, one choice is to generate the threads by thread milling on CNC machining centers. Thread milling is very reliable for automation and generates great looking threads but is somewhat difficult to apply with smaller thread diameters. In addition, the high investment costs for CNC machines make thread milled threads costly. Another more reliable way to make threads is by thread forming, and this method is also applicable for small diameters and when only simple drilling or tapping machines are available. Thread forming with centertap is a cold forming process and given the right material, it benefits not only automation, but improves the material strength by compressing it. This makes tread forming a very economical, quick and reliable alternative to tapping or thread-milling overall.