How to Size Chuck Keys

Nothing is more frustrating than losing the chuck key to your drill. Such a small object can stop your project in its tracks when you can't change your bit. If you lost the chuck, purchase a replacement. Making sure you get the correct-sized chuck avoids a second trip to the hardware store. There are more then 12 variations of chucks, so have the right information when making your selection.

Measuring your chuck makes choosing a key a simple process.

Step 1

Look closely at the chuck on the drill for the engraved numbers. The chuck size looks something like: 1/4, 3/8, 1/2 etc.

Step 2

Measure the diameter of the hole on the side of the chuck in inches with a ruler. This measurement is called the pilot shank.

Step 3

Take these two dimensions to your local hardware store to make your selection.

Bob White

Bob White began his writing career in 2006. Working in sales, he was a technical writer tasked with responding to requests for proposal. White has a Bachelor of Arts in computer science and a diploma in home inspection. He has also worked in construction, landscaping and the pool industry for more than 15 years.