Also, you need to pick a die of the same size as the rod to make it work effectively.įor example, if your rod is 3/4 inches, then the die should equally be ¾ inches. However, with the die, you will use a round rod instead of a drilled hole. Note that the dies also follow the same protocol.

Turn the tap backward, preferably 3 to four turns.

Let the tap cut threads in the wall of the hole until you reach two turns.

Place the tip of the tap into the hole in a perpendicular direction and gently press inside.

Put the square of the tap above the holder and tighten.

Using your tap and charts to confirm the correct size, re-drill the hole while creating threads inside.

First, you need to create a hole inside the material.

The following is an illustration of how best you can use these charts to make your guides: Note that it is the correct usage of taps and charts is that leads to correct guides. Taps are then placed to make guides of the right size. Once the correct drill bit is determined, the mechanists then proceed with drilling the hole up to the recommended length. Tap drill charts help machinists compare the size of a drill bit so as to come up with the right type that would create the right size of the hole. A tap drill chart will help you in the following manner: Determine the sizeīecause the types of tap and drills vary in size and materials, the charts will help you come up with an appropriate size that suits your drilling project. Generally, it is impossible for you to know the size of the tap drill to use for your screw or bolds without a good tap drill chart. In other words, it’s a device used to cut threads on a bolt (male screw). In many cases, these devices are made of carbon steel to make them strong for the job.Ī die, on the other hand, is a special tool used to cut the male portion of a mating pair of the metal fastener through a process known as threading. In other words, they are tools that are used to cut threads into a hole so that the holes can receive fasteners or bolts more effectively. Before we go deep into these items, let’s first know what they mean.Ī tap is a screw-like device used to create female screw threads. They work hand in hand to create screws, nuts and fasteners necessary for construction. Tap and Die OverviewĮvery mechanist will tell you the significance of having a tap and die in the manufacturing industry. Usually, the tap drill charts help manufacturers come up with a tightly matching pair of male and female threads. This size drill bit should be used for drilling the initial hole that will then be tapped.A drill tap size chart is a diagram from which the right sizes of the drill bit are obtained when creating an opening. Lastly, the recommended tap drill size is provided for each standard tap size. For each thread count, the equivalent thread pitch is provided and for metric taps, the approximate thread count is shown based on the pitch.

The metric system uses the thread pitch, which is the distance between threads, measured in millimeters. In the fractional and screw size systems, the thread count is used, measured in threads per inch. The thread spacing, which may be coarse or fine, is listed after the diameter. A screw size number corresponds to a diameter which is larger for a higher screw size. Fractional sizes are listed in inches, while metric sizes are listed in millimeters following the letter “M”. The decimal equivalents of the diameters are shown in both English and Metric units.

The tap size chart provides a list of standard size taps, specifying the diameter and thread spacing, for fractional, metric, and screw sizes.

Drill tap chart