The Ultimate Guide to Button Shank Types

Choosing a button? You’re spoilt for choice. Buttons come in a huge variety of colours, shapes, sizes and styles. But did you know that you have lots of choice when it comes button shank types too? 

Button shanks have both an aesthetic and practical purpose. They need to look good and fit with the style of your design. But they also need to work in terms of your production process, especially if you’re sewing buttons by machine.

Whether you’re at the stage of designing a product or buying buttons, you need to know what kind of button shank will work best for you. So take a look at our ultimate guide to button shank types for everything you need to know…

The Ultimate Guide to Button Shank Types

What is a shank?

In the simplest of terms, a button shank is the means by which a button is attached to a garment. And there are lots of different button shank types.

Different button shank types

Thread shank

A thread shank is used for flat, shankless buttons. These buttons are available in either two hole or four hole varieties. The thread shank is created as the button is sewn onto the garment.

The Ultimate Guide to Button Shank Types

Built-in button shank

Buttons without holes in their surface have a built-in button shank. This shank is a loop on the back of the button through which thread is sewn in order to attach the button to a garment.

The shank can be molded onto the back of the button during production. Alternatively, it can be constructed as a separate piece and later fixed onto the button back.

There are a number of different built-in button shank types. Here are a few:

Tunnel shank.
Tunnel shank buttons are so-called because the shank seems to tunnel through the underside of the button. These buttons attach very closely to a garment, which makes them perfect for very fine fabrics and garment embellishment.

Round, metal shank.
Round, metal shanks are usually made from copper, which can then be attached to buttons made from ABS or acrylic plastic. These button shanks allow for more space between the button and the garment, perfect for firmly attached, functional fastenings.

Square shank.
In this example we have a square shank that has been molded from plastic at the same time as the rest of the button. This is another button shank that can be firmly attached and that works well for fastening garments.

The Ultimate Guide to Button Shank Types-14

Shank measurements

If you’re planning on sewing your buttons using a button sewing machine, it’s really important that you know your shank sizes.  

The Ultimate Guide to Button Shank Types

Measuring button shanks

Here are the five different shank measurements you need to take in order to program a button sewing machine.

A: Internal height of shank loop, measured from button back to underside of the shank loop.

B: Internal length of shank loop.

C: Total height of shank loop, measured from button back to top of shank.

D: Total external length of shank loop.

E: Total width of shank loop.

Take a look at a button sewing machine in action here.

Standardized shank sizes

The size of a button shank often corresponds to the size of a button. They can usually be separated into two different categories.

Buttons of 21mm and above use one standardized size of shank. Buttons of 18mm and less use a smaller standardized size of shank.

The Japanese standard uses a third button shank size for buttons smaller than 11.5mm. A smaller shank on a smaller button looks more elegant.

Different types of shank button

The Ultimate Guide to Button Shank Types
The Ultimate Guide to Button Shank Types-06The Ultimate Guide to Button Shank Types
The Ultimate Guide to Button Shank Types
The Ultimate Guide to Button Shank Types

Shank buttons come in many different shapes, sizes and designs. Fashion shank buttons. Vintage shank buttons. Novelty shank buttons. Large, small, round, square, metal, plastic…the options are endless.

The right button shank type will enhance the design of a button, ensuring that it is both stylish and practical.

We hope this button guide has told you everything you need to know about button shank types. Subscribe for more button and garment accessory info. Or contact us today for a shank button catalogue.

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