Wednesday, September 4, 2013

Tips for Purchasing a Face Mill Cutter With Multiple Edges

By Todd Miller, Manager, Rotating Products

Today’s shops want a cutting tool that offers high productivity, versatility and accuracy at a low cost per edge. In response, cutting tool companies, including Seco, are developing new precision-based solutions that offer improved economy through even more cutting edges per insert and better efficiency by performing both roughing and finishing operations.

Double Octomill
Take the latest generation of face milling tools for example. They all feature pre-hardened cutter bodies that maximize tool life and performance, as well as make use of inserts with as many as 16 cutting edges – our Double Octomill for example  – to minimize cost per edge for a lower cost per part.

Some companies have even placed high emphasis on creating the perfect fit between the insert and its corresponding pocket to maximize the effectiveness, performance and tool life of a cutter. For instance, with our Double Octomill, we are the only cutting tool company to develop insert pockets that incorporate a strong center lock screw and precisely located HSS pins that remarkably reduce radial and axial runout.

But in order to purchase the right cutter for your needs, you must weigh the different options that are available to you, considering variables such as workpiece material and hardness, application type, cost per insert, cost of edges in the cut per load, number of indexes needed to complete a job, cutter style, cutting diameters, cycle time, and much more.

Here are some important items to keep in mind before purchasing a face milling cutter with multiple cutting edges:

• Make sure you have a wide variety of insert grades and geometries to choose from so your cutter can operate in various materials and processes. Take our Duratomic coating for example, a breakthrough in coating technologies that improves productivity and tool life in many different materials.

• With respect to insert geometry, those with small wipers are ideal for roughing operations, while wider wiper edges can perform roughing and finishing in a single operation, producing superior surface finishes. For example, our M14 geometry with a 0.45 mm wiper flat is ideal for roughing, while the M15 with a 2.11 mm wiper flat is more suitable for finishing operations. Our M13, which has the same wiper flat as the M15 but has a more positive geometry, is perfect for longer chipping materials or where reduced cutting forces are needed.

• Make sure the inserts are easy to handle and have numbering on each edge. You should index all of the inserts at the same time and in the chronological number order. By using the same edge number in all of the pockets, the inserts are oriented the exact same way as the pressing tool that produces them, which, in turn, reduces pocket-to-pocket runout so you can achieve the best possible tool life.

• Given the wide variety of machines and materials available today, it’s important to have the right cutter pitch for your face milling operation. In cast iron applications where a machine has high-power capabilities, a close pitch cutter is often the best option. However, a close pitch cutter paired with a weak machine often results in unwanted vibrations. Using a close pitch cutter in long chipping materials usually results in chip jamming in the chip flutes. Normal and coarse pitch cutters use fewer teeth/inserts in the cutter so they require less torque, making them better solutions for machines with limited power capabilities. They also have larger chip flutes, providing better chip evacuation in longer chipping materials such as steel and stainless steels.

• Given all of the different cutter options available, including 45-degree cutters, square shoulder cutters and round insert cutters, you need to determine which one brings the most benefit to your operation. After all, one option may be better if you want to reduce your cutting forces, while another may be needed for a particular part feature.

• While a high-performance cutter with multiple insert edges may cost more up front, it can save you in the long run through increased tool life, lower cost per edge and an overall lower cost per part. Keep in mind, however, not every application benefits from this type of cutter.

Because there are so many machining variables to consider, you should also evaluate the cutting tool company selling a particular cutter and see what level of customer support it provides. After all, application support can be a major source of improved productivity, but it is one manufacturers often overlook.
Utilizing a cutting tool company’s in-depth knowledge of manufacturing technology as a resource allows you to stay abreast of the latest advancements in manufacturing, as well as understand how those innovations play into process optimization. The end result is that you can continue to increase your competitive advantage and differentiate your shop as a technology leader in the increasingly challenging global market.

About the Author
Todd is the manager of rotating products for NAFTA, responsible for solutions and applications involving face, square shoulder and disc milling. Todd and his team of product experts are dedicated to providing a consistent, high-level of support to Seco customers throughout the United States, Canada and Mexico. In his spare time, Todd likes to bowl and cheer on the University of Michigan football team.