Forstner Bits: What Are They and What Are They Used For?

To drill wide but also blind holes in wood, there is a ready-made solution: Forstner bits. In this case we are not dealing with a cylindrical and sharpened tool for drilling the material in question. The shape is circular but flat.

Then there are the blades that form a mill. These elements allow drilling up to a certain point. Forstner bits are perfect for performing specific work in wood, such as creating spaces for adding hinges to furniture doors. but not only. Here's everything you need to know about these precision tools, which are loved by those who work with wood.

What is a Forstner drill bit

With this term we mean a tool that is mounted on manual or column drills to make precise and flat, but also blind, holes in wood. This means that you cannot drill through from side to side on the plane you are working on.

This type of bit was invented by Benjamin Forstner in the late 19th century. How is it made? The tool has a cylindrical shank that inserts into the traditional drill chuck and with a final part shaped like a disc with variable thickness and diameter.

There is a central point that guides the cut and a profile with a sharp edge proceeds with the machining. This element is made of blades for cutting wood, and the shape is such that the Forstner mills are often called butterfly bits.

What are Forstner bits used for?

The ultimate goal is to create a circular and blind shape with a well-defined diameter and precise depth. The width of the holes is usually wide but not excessive, especially because in the latter case the hole saw is preferred.

Often the Forstner bit finds widespread use in furniture work but it's not the only reason why this tool is found in workshops and carpentry shops. Often the butterfly mill is crucial for creating holes needed for mounting handles and knobs.

How do you use this tool?

Actually, there are no particular precautions to observe when using Forstner bits except those that apply to any other drilling activity. In short, you insert the shank of the mill into the chuck and fix the element. Usually the best results are obtained on work that involves a column drill with reduced speed: in this way precision can be achieved.

Some models of Forstner mills

In addition to the classic structures, namely two-flute Forstner bits in HSS steel like those you find in the Krino catalog and ranging from 15 to 35 millimeters in diameter, you can also buy and use models for specific uses.

Also in our catalog you'll find mills for dowels and for hinges. This way you can perform work with extreme precision for any type of furniture work. And more generally, to drill a hole in wood with specific technical characteristics.