How do the drill and tap match？

Tap and drill are often used in machining tools, they have an important role in the processing of metal materials. A tap is a cutting tool used to process threads, while a drill is a cutting tool used to process holes. The correct matching of drill and tap can improve work efficiency and quality.

Under normal circumstances, the selection of drill bit is determined according to the diameter of the thread, that is, drill diameter = nominal diameter of thread - pitch, such as M3x0.5 thread, using 2.5 drill bit (3-0.5); M5x0.8 thread, using 4.2 bit (5-0.8). In actual use, the bit diameter can also be slightly enlarged, such as the thread of M5x0.8, which is also useful for 4.3 bits.

When the drill bit and tap are used together, the drill bit should be used to drill holes on the workpiece first, and then the tap is used for tapping. The specific operation sequence and precautions are as follows:

1.Preparation: Select the appropriate drill and tap, prepare the lubricant and handle.

2.Drilling: Use the drill bit to drill holes in the workpiece, making sure that the diameter of the hole is slightly smaller than the diameter of the tap.

3.Tapping: Align the cutting part of the tap with the drilling hole and apply light pressure at the appropriate Angle to make the tap start cutting. Rotate the tap at the appropriate speed while pushing forward so that the tap gradually cuts out the thread. Be careful to maintain a steady force and speed.

4.Cleaning and lubrication: Regularly clean the chips on the tap, and apply lubricants on the tap during the cutting process to reduce friction and heat and improve the cutting effect.

5.Note: Choose the right tap, pay attention to the cutting force, use lubricant, clean the tap regularly, and pay attention to safe operation.

The above is the correct sequence and precautions for the use of drill and tap. Following these steps and tips can help you thread more efficiently and ensure job safety.