Grooving processes play an important role, especially in mass production. The trend towards miniaturisation of even complex component geometries is one of the driving forces, especially in the field of parting off and grooving tools. For several years now, Walter Tools has been known for its technological expertise in this area.

Markus Stumm, Product Manager for Grooving at Walter, states: “We have significantly expanded our portfolio in recent years. In 2020, we will further strengthen our activities in this field. With the Walter Cut DX18, we are launching a tool with innovative clamping that will set completely new standards.”

Conquering a conservative market with innovative solutions

Users are particularly conservative when grooving. Stumm explains: “In mass production, when the process is running reasonably well, manufacturers rarely change the tooling system. We have to offer a clear advantage in terms of productivity and cost-efficiency to get to the machine. Problems with process reliability with the existing tools, or when a machining strategy is changed, provide us with an opportunity.”

The parameters according to which the decision for a parting-off process and the corresponding tools is made, are machine run times, tool life and process reliability. Typical problem areas, especially for machining operations grooving deeper into the workpiece, are the stable fixing of the indexable inserts, chip breaking, and cooling. Users who want to play it safe, therefore reduce the cutting data below the recommended values. Who wants to risk stopping the production process due to chip jams, a vibrating tool or even if a cutting-edge breaks?

This is exactly where the Walter grooving experts come in: with its portfolio of grooving tools, Walter already covers a wide range of grooving applications. Walter Cut DX18 is a double-edged system for grooving and parting off, especially on Swiss type auto lathes or multi-spindle machines.

Walter Cut DX18 – maximum stability,convenient changeover

The Walter DX18 system is suitable for parting diameters of up to 35mm. With the innovative, patent-pending positive engagement system, Walter’s developers are addressing the fundamental problems of narrowly dimensioned parting-off tools: the stability and handling of the cutting insert. In conventional screw clamping, the cutting forces act in such a way that the existing clamping forces are not sufficient – with negative effects on machining quality and process reliability. In contrast, the new Walter Cut DX18 cutting insert geometry locks the insert securely via positive engagement.

Another innovation is the SmartLock system, which considerably simplifies insert changeover. With conventional screw-clamped systems, the machine operator has to remove the entire tool for this purpose – and this in cramped and not always user-friendly, “oily” machine conditions. With the Walter SmartLock system, the clamping screw is located on the side of the tool: simply insert the screwdriver, unscrew and change the indexable insert. Due to the positive engagement, the new cutting insert adjusts 100% correctly, even with very narrow insert widths.

The potential of the system was successfully proven in a tool life test on a Swiss-type auto lathe. An outer diameter of 12mm was parted off from 1.4057 material. The cutting-edge width used was 2mm.

Stumm explains how tool life has increased drastically: “With the new double-edged Walter Cut DX system, we were able to more than double the tool life compared to the single-edged competitor – with maximum process reliability and productivity. The customer particularly liked the fact that they no longer had to remove the tool for changing the insert.”

Process reliability in focus: Walter Cut GX and MX systems

The new DX system is the latest example of the Walter team’s high capacity for innovation in the field of grooving and parting-off. With the double-edged Walter Cut GX34, the development engineers have already shown the optimisation potential that lies in targeted technical improvements. In the meantime, the system has established itself as a reliable problem-solver for parting-off diameters up to 65mm.

For example, a well-known customer from the automotive supply industry repeatedly experienced major problems with process reliability when parting-off drive shafts (nitriding steel with a diameter of 60mm). Stumm and his team were given the opportunity to bring the double-edged Walter Cut GX34 system onto the machine. Since its design has been optimised for the stability of the long cutting insert, the Walter system significantly reduced vibrations that previously occurred during machining. The feed during parting-off could therefore be increased by 30% and the tool life quantity doubled. A further economic advantage resulted from the double-edged grooving insert instead of the single-edged competitor.

The Walter Cut MX with four cutting edges has proven to be particularly reliable, highly accurate and cost-efficient for the production of small precision parts up to a cutting depth of 6mm and insert widths from 0.8mm to 5.56mm. The self-aligning, tangential clamping of the system and the dowel pin location in the insert seat, lead to greater repeat accuracy, stability and process reliability. The special insert geometry also ensures that the inserts cannot be fitted incorrectly.

During a tool life test in a large-scale production setting on a Swiss-type auto lathe, the task involved parting-off precision stainless steel pipes with an outer diameter of 5mm from 1.4301 material. The cutting width used for this is 1mm. The system impressed with a significant improvement in tool life.