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HORN: High Performance in Stainless Steels

Horn has developed a new, solid carbide milling cutter range especially for machining stainless steels. The tools are for milling stainless materials in the food, chemical and pharmaceutical industries as well as the precision engineering and watchmaking industries. In addition, due to their geometry and good chip breaking, the milling tools are suitable for machining numerous other materials. Due to the precise combination of the substrate, the macro and micro geometry as well as the IG3 coating, the milling system exhibits high performance and long tool life. The coating in particular offers high temperature resistance for machining steels alloyed with chromium, nickel and molybdenum.

Horn offers the solid carbide milling tools from stock in two types. The DSHPR variant is suitable as both a finishing and a roughing tool. The geometry is also adapted for trochoidal machining and plunging. The DSR type, with its very sharp cutting edge geometry and short design, is suitable for very small parts and unstable clamping conditions, such as in the medical and watchmaking industries. In the DSHPR line, all tools are available with four teeth and in diameters from 2 mm (0.079″) to 20 mm (0.787″). Horn offers the DSR variant with three teeth in diameters from 1 mm (0.039″) to 10 mm (0.394″).

Cool Clean: CO2 Machine Tool Cooling Solution

Dry machining is essentially machining without the use of any cutting fluid or coolant. Dry machining is typically reserved for certain applications, and it may never completely replace the use of cutting fluids, but is becoming increasingly popular due to:

Operator Safety – Reducing fumes and splashing coolant
“Dry” may work better for certain metals (Ex. composites, plastics)
Eliminates messy work environments

Cool Clean has made significant advancements in dry machining with the ChilAire™ CO2 Machine Coolant Systems. The ChilAire™ offers the performance benefits of a liquid coolant and the environmental benefits of dry machining, all with great economics.

Dry Machining Features:

Benefits operations that must be “dry”
External and through tool cooling capability
Precision machining of plastics, PEEK, UHMW, etc.
Increases in tool life and tighter hole tolerances
Additional capability can be achieved with MQL for certain applications

The process is straightforward. CO2 spray is created through an expansion of liquid CO2 into solid CO2 crystals, or CO2 snow, that are delivered to the machining cutting zone. When the CO2 spray hits the cutting edge, the ice-crystals melt and flash back to CO2 gas in a process called sublimation – capable of absorbing significant amounts of heat. The ChilAire™ system keeps the tool and work piece at ambient temperature, hence preventing thermal shock. Further, by controlling the temperature of the cutting zone, customers can use lower cost cutting tools on applications that typically require expensive tools such as Cubic Boron Nitride (CBN), Ceramic, Polycrystalline Diamond (PCD), etc.

Benefits of the ChilAire™ are as follows:

Clean Operator Work Environment
No Splashing Coolant
Cutting Tool Does Not Experience Thermal Shock
Improved Economics
No Secondary Cleaning

HORN: Superfinishing of Bores with Supermini System

At EMO 2023 in Hannover, Horn is presenting an innovative extension for the Supermini system in the field of ultra-fine machining. The precision tool manufacturer has added a variant with a precision-ground rake face to the Supermini system especially for ultra-fine machining of bores. Due to precision grinding of the cutting edge, it is free from notches when magnified approximately 200 times. The tool system can be used from an inside diameter of 0.3 mm (0.012″). The sharp insert geometry enables process reliability even with very small infeed and cutting feed rates. The specially developed coating is suitable for stainless steels, non-ferrous metals and other metallic materials.

The insert of the Supermini Type 105 system requires only one tool holder for well over 1,000 insert variants. This applies equally to left-hand and right-hand versions. The carbide inserts are available in coated and uncoated versions in different grades for every application including hard machining up to 66 HRC. The patented droplet shape of the cross-section has a vibration-damping effect and delivers excellent repeatability when changing the insert. Internal coolant supply to the insert increases tool life, enhances cutting performance and improves chip removal. Horn offers the tools with elements for face clamping. This allows, for example, the insert to be changed easily without having to remove the holder from the machine.

History Horn Supermini:

In 1989, HORN launched the technically superior Supermini system at the world’s largest metalworking trade show, EMO in Hannover, Germany. After considerable technical development, it was possible to successfully manufacture precision internal grooving tools for bores down to 5 mm (0.197″) in diameter. The Supermini system was born and over time became one of Horn’s most successful products. In addition, the Supermini system was the first precision tool to benefit from Horn’s own in-house coatings.

HORN: Optimized for Swiss Type Lathes

Optimized for Swiss Type lathes

Paul Horn GmbH has never stopped developing and optimising its product portfolio. At the same time, it has integrated almost 100 percent of the added-value creation into its own production. The range of applications of the tool systems has grown considerably. Today’s machining operations across a diverse range of materials constantly demand further development and adaptation of the tool systems. Grooving with indexable inserts has become indispensable in modern production. Radial grooving, parting-off, axial grooving and internal grooving to micron precision are now part of everyday life in industry. For such machining processes, Horn relies on the S224 insert system, among others.

Horn has revised the clamping of the S224 type indexable insert for use in Swiss-type lathes. In order not to have to remove the holder for indexing or changing the insert, the Horn engineers relocated the clamping screw to the side. Clamping now takes place via a camshaft. This allows the insert to be clamped quickly at either side of the holder without having to remove it. Furthermore, this type of insert also eliminates the need to invest in special quick-change systems. For the user, in addition to simple operation with a torque wrench, there is the advantage of reduced machine downtime due to faster set-up. Horn offers the holder system from stock in left and right versions as a 16 mm x 16 mm square shank. All variants of the holder are equipped with an interface for internal coolant supply from above and below.

HORN Mastering Processes: Hard Machining

Mastering Processes: Hard Machining

Shorter machining times, high surface quality and the saving of grinding operations. These are just three of the advantages that hard machining with a geometrically defined cutting edge can bring to the user. With a high level of know-how in tool technology, Paul Horn GmbH offers numerous tool solutions to economically machine steels harder than 56 HRC. The cutting material CBN has proven itself suitable for grooving operations.

CBN (cubic boron nitride) is the second hardest known material on earth after diamond. Tools made of CBN wear much more slowly than other cutting materials when used appropriately. On one hand, this makes it possible to achieve higher shape and dimensional accuracy, and on the other hand, hard materials (steel up to 70 HRC) can be machined reliably. There are no different grades of CBN. Differentiation is made by the CBN volume fraction, the fillers, the grain size and the ceramic/metallic binder phase (cobalt/nickel). This results in different CBN substrates. Numerous tool systems from Horn can be equipped with the cutting material CBN. In most cases, these are tools specially adapted to the respective application. However, Horn also offers standard tools equipped with this very hard cutting material.

Hard machining with CBN cutting materials is usually done dry. This is possible because the cutting material has high heat resistance and the high temperature within the chip formation zone has a positive effect. An insufficient supply of coolant or interruptions in cutting lead to high, thermally induced stresses in the structure of the insert. This can lead to cracks in the structure and thus possibly destroy the insert. During hard machining, the steel in the shear zone undergoes intense heating and is thus softened. Most of the heat generated in the shear zone is dissipated via the chip and not transmitted into the workpiece. This means that there is no thermal influence on the insert edge in the process. While carbide suffers a massive loss of hardness at around 800 degrees Celsius, the hardness of CBN remains almost unchanged even at up to 1,200 degrees Celsius. Another important aspect is the chemical resistance, especially at the prevailing temperatures.

Numerous Advantages

Hard machining with a geometrically defined cutting edge in combination with CBN has numerous advantages over grinding . High metal removal rates are possible with this process, which results in shorter machining times. Conventional machines may be used. This offers the possibility of complete machining of the component. Even complex contours can be easily produced on a lathe. With grinding, on the other hand, the wheels have to be elaborately profiled. The high surface quality that can be achieved with hard turning also saves on further grinding operations.