Deburring bore holes


Deburring. Safe and efficient.

HSD deburring tools are used in highly automated processes for deburring of bores. The reasons for automation of deburring are often large quantities, short deburring times, high reproducibility of the result or the rationalization of manual deburring.

Remove the burr where it originates.

HSD tools are used in machining centers, lathes and milling machines, deburring stations or robot-guided in deburring cells. Deburring can be integrated into the process or added as a separate process step.


Workpiece and HSD tool - stepped bore and crossing bores

Bore entry, Stepped Bore, Slot, Groove, Bore exit

Several intersecting holes are machined through the main hole with only one deburring tool in one step. All intersecting holes are deburred, even with different diameters.

The smallest tool diameter currently used is about 2mm. This is the diameter of the main hole through which the tool enters. The smallest cross holes to be deburred are in the diameter range around 1mm.

Step tools can be used as special tools for stepped bores with changing diameters, with the cutting edges being arranged in different diameters and levels. In this way, multiple cuts can be deburred simultaneously with one tool.

Special solutions are also developed for other special cases.

The processing of a slot, a groove or an elongated hole does not differ in principle from that of a cross hole. Here too, all intersections are deburred in one operation. The use of combined inner and outer deburrers is particularly effective for slotted shaft ends.

Hole exits are also deburred with HSD tools. These are often non-flat, curved or stepped exits, resulting from geometries in complex intersections.

Geometries to deburr by HSD - crossing bores of different diameters
Geometries to deburr by HSD - slots crossing bore
Geometries to deburr by HSD - curved or stepped bore exit and grooves

In forward and backward machining by the HSD tool in clockwise and anti-clockwise rotation, all edges of an intersection are deburred.

The cutting force is controlled directly by the pressure. This control by air (e.g. in the deburring station) or coolant (mainly in the machine) enables higher speeds and feeds. The necessary cutting force can be  adjusted optimally.

The cutting edges are flexible supported and are controlled by pressure, i.e. the cutting edges can be “extended” exactly at the cross hole to remove the burr. In addition, for processing the pressure at the cutting edges can be adapted to the burr strength and size to be removed.

The detached burr and existing chips are washed away by the coolant or compressed air flowing out at the cutting edges. This minimizes the influence on the roughness of the workpiece surface. Special cutting edges are used for particularly high surface requirements.

Deburring tools for larger bores

Frequently asked Questions

Removing burrs from chipping processes: drilling, milling, reaming, …

Materials: Steel, cast iron, aluminum, brass, …

Typical workpieces are shafts with oil drillings (gearshaft, crankshaft, camshafts, …) machine or motor housing, mechanical bearings, pneumatic and hydraulic parts.

Different geometries for HSD tools to deburr

Typical applications are crossing bore holes. Especially intersections of deep hole drillings and several also different crossing oil bores are deburred by HSD tools. Applications of one tool for different intersections are possible. Combinations of different HSD tools in one combined tool for stepped main holes are possible (ref. also special HSD tools).

Deburring at drill entry and exit, particularly non-flat, stepped, curved intersections.

High speed deburring tools are made for highly automated processes. Therefore this HSD tools are used for high quantity or mass production, short cycle times, short deburring times, reliable repeatability of the result and rationalisation of the deburring process.

The installation of deburring tools is in practice in milling, turning and other CNC machines – to take an advantage on the machine where the burr is produced. Other applications are by deburring stations and robots in post-processing.

HSD application - coolant control

Machines should have left- and righthand rotation, pressure supply at the deburring tool similiar to internal coolant by coolant fluid, water, oil, air (application without pressure ref. special HSD tools).

Cutting edges of HSD tools are mobile to follow contours and compensate tolerances. There are no spring or spring-like elements. The cutting edges and the force is controlled by pressure. During operation the tool is rotating and the cutting edges are passing the intersections in left- or right-hand rotation.

Function of the HSD deburring tools

The HSD tool is producing a chamfer. The characteristic of the chamfer is controlled by pressure, rotation and feed.

HSD deburring tools are available and in practice starting in the diameter range from 2 mm. There are no restrictions for larger diameters. Cross holes are deburred up from approximately one millimeter. The tool length is adapted to the needs of the customer. Very slim tools with a ratio of diameter to length of 0.012 have been used for deep hole drilling for years.

HSD deburring tools - small and larger diameter

HSD deburring tools in frequently needed diameters and lengths are on stock. There is no catalog, because the tools are tailor-made to the requirements in various designs and with numerous options. After the deburring task has been described, the tool is designed to fit to the application.

HSD deburring tools - examples

The HSD principle can be applied to various deburring tasks. Variants and combinations of several tools and functions are possible in one tool. The HSD technology can also be implemented without the pressure-controlled function, then there is no internal cooling or pressure media necessary.

Multiple cuttings can be used in one tool

Combining HSD Tools

In combined HSD deburring tools, several cutting edges are arranged on different levels. Different diameters can also be combined. This means that all cross holes in deep holes or stepped holes are deburred with one tool in one step.

Stepped HSD tools for stepped holes and multiple crossings

HSD tools without pressure control

If there is no pressure medium available on the machine, the cutting force can be applied by means of an elastomer core in the tool. “Dry machining” without coolant is possible with this variant.

More simple HSD tools without pressure control

Special HSD variants

Some examples: Variants for the application of HSD technology are used for deburring slotted pipe ends. Deburring is done inside and outside at the same time. Another variant is used for robotic deburring. The tool heads are designed to compensate expected higher tolerances in positioning. Different cutting edges are used for HSD tools. Among other things, cuttings with a large range of action are used for deburring hole intersections inside undercuts.

HSD tools are designed to fit the customers requirements

We advise our customers on the possible applications. After an analysis of the task, the optimal HSD tool is designed.

Analysis, Consultation

HSD tools are designed to fit the customer’s requirements. Basic information must be available first. Basic information concerns the burr:

  • the geometry of the workpiece and the location of the burr,
  • the pre-processes that create the burr
  • the material of the workpiece.

Other requirements as:

  • quality of the surface,
  • dimension of the chamfer,
  • possibilities to reach the burr,
  • cycle time in application.


  • Maschine (type, equipment,…),
  • available pressure and media,
  • relevant post-processes.

This is the basis, we analyze and recommend.

Concept, Design and Quotation

After the analysis, the tool is designed for use. For the various requirements, the required tool properties out of the proven solutions are combined. An HSD standard tool can be the right for the tasks or a new special solution for more complex applications can be developed.


We make the HSD tool  – the design and manufacturing. We will accompany the introduction in the production process when the working parameters will be tuned in detail.

Owner Dr. Reinhard Nothnagel HSD-Entgraten

"The HSD deburring tools are tailor-made precisely to the customer's requirements"

We support you in solving the deburring task based on our decades of experience. The further development of the deburring tools is in our hands. We cooperate directly with the inventor, the Dr.Beier-Entgrattechnik.

Dr.-Ing. Reinhard Nothnagel
Company owner & managing director

Inquiry - Analysis - Advice - Order

The HSD deburring tools are special tools that are individually adapted and manufactured to the component to be deburred and the process.

The following information will be very helpful in advance:

  • Component drawing, sketch or photo of the location of the burrs to be removed
  • Short hint on the origin of the burr, machining sequence
  • Are there requirements for the chamfer or roughness after deburring?
  • Is a cooling medium or compressed air available? What pressure is on or can be set?