Frezy obrotowe

Cromwell stocks a wide range of rotary burrs ideal for metal fabrication applications. With well-known brands such as Dormer®, York® and Kennedy®, you'll be assured of finding the right tool and quality.

What are rotary burrs?

A rotating tool, a rotary burr is used for removing material from a work piece by rotating at high-speeds. They can be used in several metalworking applications including, deburring, shaping and hole enlargement. Usually comprised of either tungsten carbide or high-speed steel they can be used on a wide variety of metals (especially carbide burrs) from soft metals like aluminium to stainless steel.

Tungsten carbide burrs are typically used on harder metals as they feature greater hardness and resistance to heat. HSS burrs are mostly used on softer metals, this is because they have less tolerance to heat and wear, although they are less brittle than carbide burrs.

As well as different manufacturing materials there are also different types of cutting face and head shapes, that are suitable for different applications.

Types of burrs

The cutting face of a rotary burr is the end that removes stock material from the work piece, typically there are two types of cut single cut (also known as Aluminium cut) and double cut (often referred to as diamond cut).

• Single cut - features a single right hand spiral flute and are most commonly used on ferrous materials such as cast iron, copper and aluminium. They provide a faster cut with minimal clogging but sacrifice the accuracy of the finish.

• Double cut - have both right and left handed cutting angles and are commonly used on hard metals to produce a finer finish.

As well as the types of cut the head shapes of rotary burrs determine what applications they are best used for.

• Cylindrical end cut - This head shape is ideal for surface milling, right angle corners.

• Cylindrical ball nose - These types of burrs are used for machining contours and circular arcs.

• Ball shape - These burrs are typically used for rounded end milling and preparing a surface for welding.

• Oval shape - The oval shaped head is mostly used in rounded contouring and end milling applications.

• Tree shape round nose - Mostly used in multi-angle contouring, these burrs are rounded and narrow.

• Cone shape round nose - These types of burrs are mostly used for enlarging holes, rounded edges and narrow places.

• Flame shaped - Used in applications involving round edge milling and preparing for welding.

• Tree shape pointed nose - These burrs are used in multi angle contouring, pointed and narrow places.

Considerations when choosing a rotary burr

As well as taking the above information into consideration the size of the burr is also a determining factor when it comes to usage. As a general rule smaller rotary burrs are used to produce finer smoother finishes whereas larger burrs are used in in applications involving large and fast stock removal.

FAQs

What are rotary burrs used for?

In essence rotary burrs are used to remove stock from a work piece. Depending on the type of burr, they can be used in several industries in an around metal fabrication. Typical uses include tool making as carbide burs in particular are hard enough to grind tool grade steel.