Tapping holes is a key part of many construction and repair projects. But how do you know what size drill bit to use to create the correct size hole? That’s where the tap drill size formula comes in.

In this blog post, our engineers will explain the tap drill size formula and how to use it to get the right fit for your project.

What is the Tap Drill Size Formula?

The tap drill size formula is a simple equation that gives you the right drill bit size to create a hole that’s the right size for the tap you’re using. The formula is as follows: 

Drill Bit Size = Tap Size x 0.8

For example, if you’re using a 12mm tap, the formula tells you to use a 9.6mm drill bit. 

How to Use the Tap Drill Size Formula 

Using the tap drill size formula is simple. All you need to do is determine the size of the tap you’re using and then plug that number into the formula. The result will give you the correct drill bit size for the job. 

One thing to note is that the tap drill size formula works best when used with metric taps. If you’re using an imperial tap, you’ll need to convert the size to metric before you can use the formula. 

Conclusion

Tapping holes is an important part of many construction and repair projects. To get the right fit for your taps, you can use the tap drill size formula. The formula is simple and easy to use.

All you need to do is determine the size of the tap and plug that number into the equation. With the right drill bit size in hand, you’ll be able to get the perfect fit for your project.