We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.
Machinery

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

What is a Jacobs Taper?

By Paul Scott
Updated: May 17, 2024
Views: 10,043
Share

The term Jacobs Taper refers to one of a family of tapered machine tool shafts used to lock the tools in place in drill presses, lathes, and milling machines. This group or family is collectively known as machine tapers and offer a cheap, efficient alternative to conventional jawed chucks. The machine taper has been in use since the earliest manual drill, milling machines, and lathes and is still used as a reliable tool mounting system on modern computer numerically controlled (CNC) machines. Unlike convention chucks which rely on the pressure exerted by three or more jaws to secure a bit or tool, the machine taper relies simply on the friction across its surface and the pressure against the work piece to hold it firmly in place.

The different members of the machine taper family all work on the same basic principle. The tool shaft is tapered and is simply inserted into a similarly profiled socket in the machines head or chuck. Friction across the two mated surfaces and the pressure exerted by the work piece hold the tool firmly in place. This simple system produces considerable torque transmission and a very secure grip on the tool. These tool shafts and their corresponding chucks typically have a slot cut through them allowing a wedge to be used to dislodge the tool when the job is complete.

Other variants in the machine taper family include the Morse Taper and the Brown and Sharpe Taper. These machine taper groups all feature a set of different sizes graded according to their taper profiles which are defined by three basic dimensions. The first is the diameter of the taper at its broad end or major diameter, the second is the diameter at the narrow end or minor diameter and the third the axial length between the two. The Jacobs Taper is generally represented by ten different sizes all of which are typically used in light load applications such as drill presses.

Jacobs Taper chucks are far cheaper to produce than conventional jaw types and tools may be changed a lot quicker using this system. The Jacobs Taper and its counterparts in the family have been in use for many years and are still popular tool-locking options even on modern CNC machines. The Jacobs Taper chuck and tool shaft system is most commonly found on larger, commercial drill presses although smaller do-it-yourself (DIY and hobby machines are available with the locking system.

Share
WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Editors' Picks

Discussion Comments
Share
https://www.wisegeek.net/what-is-a-jacobs-taper.htm
Copy this link
WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.