About this deal
First up, we have the trusty old steel taps. These bad boys are a reliable option for those on a budget but remember that they might not be the best choice for heavy-duty or precision work.
1/8 BSP and 1/8 NPT Taps and Dies – Best Fittings
In this example, we are modeling a standard pipe, 1-1/2 NPT Pipe Size, at 11-1/2 Threads per Inch. We will use specific points on this reference sketch to define our pipe. These values may also be acquired using the formulas contained in the ANSI/ASME B1.20.1. Note that the listed dimensions are in inches and are given to four or five decimal places only to avoid errors in computation, these do not indicate required precision.Pitch, P: Corresponding to the Threads per Inch of the given pipe, e.g. this 1-1/2 NPT Pipe Size at 11-1/2 Threads per Inch will have a pitch of 1÷11-1/2 or .087. If you’re working with a 1/8″ NPT tap, one of the key things you need to know is the correct drill bit size. So, let me clear that up for you!
NPT Threads in SOLIDWORKS Using the Hole Wizard Feature Creating NPT Threads in SOLIDWORKS Using the Hole Wizard Feature
Create a Sketch on the Right Plane which intersects the helix created. On this sketch we will define the thread profile. Overheating can cause the bit to wear out, break, or damage the material you’re drilling into. Taking a breather is a small effort that can make a huge difference!For other types of tapered threads such as Aeronautical National External Threads, ANPT, the end must be chamfered 45° with a specified depth define in the ASE AS71051 Standard.
NPT (National Pipe Taper) HSS Ground Thread Taps, Straight
I recommend high-speed steel taps if you’re looking for something with a bit more oomph. These are specifically designed for fast cutting and feature excellent wear resistance.Now, for the drill bit size, the secret lies in subtracting the pitch of the thread from its diameter. For a 1/8″ NPT tap, the magic letter is anR-shaped drill bit. First, you’ll want to ensure you got the right size drill bit. In our case, we need anR-shaped drill bit equivalent to 0.339 inches or 8.61 mm. Create a Sketch on the rear face of the extrusion and draw a circle equal to the outer diameter of the pipe.
