What you need to know to better tool up your Swiss machine

Tungaloy’s ModuMiniTurn QC10 modular turning tool system offers an extensive selection of modular heads for applications including forward turning, back turning, grooving, parting, and thread turning. Tungaloy

In Swiss machining, tool selection is all about balancing flexibility, efficiency, and precision. Having a diverse set of modular tools in your Swiss machine’s tool rack makes sense.

The number of tools a Swiss-type CNC lathe can hold depends on the machine brand, model, and configuration. Entry-level machines can often hold between 12 to 20 tools, mid-range machines between 20 to 30, and top-level machines between 30 to more than 40 tools.

The smaller the tool rack, the more strategic you need to be with tool selection.

But before deciding on tooling options, there are a few things to understand about Swiss machines that will help you create robust tooling setups.

If your shop is new to the Swiss machining world, it’s important to understand the equipment principles and machining strategies suited for the process.

“The guide bushing and the sliding headstock mechanism are what make a Swiss machine unique,” said Scott Laprade, applications supervisor at Genevieve Swiss Industries, Westfield, Mass. “Sometimes, new users come from a lathe background, which helps, but it is a totally different process with a unique tooling strategy.”

It is easy to fall back on familiar tools, such as ISO-style insert systems like DCGT or VBMT tools. These tools may work on a Swiss machine under certain circumstances, but oftentimes there are better tools designed specifically for this type of equipment.

There is no one-size-fits-all approach to tooling up a Swiss machine because every application is different. A medical manufacturer of screws will require different tools than a manufacturer of firearm components. The features are different, so the tooling needs to reflect that.

“Work with tooling sales or engineering for help with choosing the correct tools and cutting conditions for the workpiece,” said Steve Easterday, Swiss application manager at KYOCERA Precision Tools, Hendersonville, N.C. “Not knowing the specific tooling and insert grades is a big mistake; a workpiece drawing should be provided so both tooling sales and end users completely agree.”

The goal of a Swiss machine is to produce a component in one pass, unlike CNC lathes, which often require roughing and finishing passes.

GenSwiss' CUT 3000 Series includes a large selection of cutting geometries with assorted chip breakers, specifically designed for small to medium sized parts manufacturing. Indexable Inserts are designed to be easily mounted onto compatible tool holders, making them replaceable when the cutting edge becomes worn or damaged. GenSwiss

All the tools should be designed around that concept. Using tools that are designed for Swiss versus using general-purpose lathe tools will help ensure efficiency and increased productivity.

“It’s important to take the time to review new and innovative tooling options,” said Jason Bainbridge, product manager at Tungaloy Canada, Brantford, Ont. “Don’t just stick with existing tooling because that’s what’s worked in the past. There are some new advancements, especially around modular, quick-change products, that make a lot of sense for Swiss machining.”

Swiss machines are small and have very little space to work around. Tools designed specifically for these machines can make machine setup easier. Some tools require the operator to reach inside of the machine to change the insert, which is where modular systems can help.

“With modular tooling, you can easily pop the head off the tool, change the insert, and pop the head back into the machine,” said Bainbridge. “The work is done at a bench rather than the operator needing to hang into the machine.”

These machines have a history that dates back over 100 years and were developed in Switzerland to make watch parts. At that time, one-piece tools were hand ground to different shapes. However, with modern-day technology, the tools can have replaceable tips, eliminating the need for operators to grind their own tools.

“There are tools that offer an interface between the shank and the insert, which is a modular type of design,” said Laprade. “With this, you can buy one style holder with dozens of geometries to fit into the toolholder pocket. One day, you could use the system for a cutoff tool, the next for threading. It’s very simple. Shops don’t have the time to teach people to be tool grinders and instead can employ modular tools to make the process more efficient and profitable.”

Modular tooling allows for quick versatility between components, allowing operators to change the setup quickly and save downtime.

Bainbridge noted that it can sometimes experimentation is required to figure out the right pieces needed, but with the foundation of modular tooling system setup, it is easy to change and customize this operation to exactly what you needed.

You also could consider employing a two-head strategy for the shank, where rather than changing out an insert, you’d exchange the head with one that has a new insert.

“With very complex parts, and depending on the tool changer capacity, you may run out of tooling stations,” said Laprade. “Modularity is one way to problem solve, but another is to double up geometries on one station. Look for tooling that has a twin pocket design, where it can have a grooving and threading tool both on the same tool station. This gives you a little bit of extra versatility.”

KYOCERA's JCTM line for Swiss machining applications feature coolant connections directly to the tool post. These versatile holders are designed to take advantage of different coolant supply styles and can support internal coolant with or without piping systems. KYOCERA

Every Swiss machine setup requires core tools that cover a range of operations.

According to Easterday, the standard tooling that should be considered includes cutoff and outer diameter (OD) turning tools. Depending on the features of the workpiece, OD grooving, OD back turning, and OD threading also should be considered.

For internal operations on the workpiece, carbide drill, inner diameter (ID) boring, ID threading, and internal broaching should be considered.

The following are some of the general basic tool categories to consider:

“You want to build the foundation with your turning tools, and at the most basic level, you need sharp turning inserts,” said Bainbridge. “Then you can move to parting off or threading, but keeping everything modular will help build an adaptable foundation with additional pieces that you would need as you go.”

He added that when it comes to threading, it’s important to have the ability to create different threads using a single-point threading insert. Look for quick-change milling tools such as an indexable milling tool or solid carbide with a replaceable head. An exchangeable-head drilling system is recommended.

The challenge you’ll potentially face is deciphering between so many different choices. For example, cutoff tools come in various thicknesses, lengths, and shapes.

“We want to steer people in the direction of a tool suited for the material they are working with,” said Laprade. “If you have a workpiece that is beryllium copper, that will cut very differently from 17-4PH or INCONEL. Different geometries perform differently. Be sure to understand the requirements based on what you are making and the material you are working with.”

Easterday added that when it comes to selecting basic tools, it’s important to know if that machine is equipped with a high-pressure pump to allow for coolant-through tooling.

Once you have the basic set of tools, moving to advanced options can help round out the setup.

In some scenarios, it may be prudent to limit the tool variety. For low-mix/high-volume production, stick to optimized tools for the application that will help reduce cycle times. If the machine has a limited tool changer, prioritize essential and multifunctional tools.

While selection depends on the number of tool change stations available, there are some common tools to consider.

“Additional tool selection will depend on the features of the workpiece but can include thread whirling, rotary B-Axis, rotary broaching,” said Easterday.

For the most part, choose secondary tools based on the application and workpiece material.

While not every shop is going to have the same needs or requirements, the following are some examples of applications that would benefit from secondary tools:

For high-precision or micromachining:

For lights-out or high-production machining:

For tough-to-machine materials:

Some shops may require specialized operations for a given application that may not be commonplace.

For example, Laprade noted that rotary broaching tools can be used on a Swiss machine to cut hexagonal drive features, like those found at the end of a screw for an Allen key.

“Another technology that could be added is knurling, which is a process that maybe not everybody would require,” said Laprade. “Knurling tools for Swiss machining need to have a low profile because of the guide bushings and tight tooling layout. You can’t just use one from a CNC lathe.”

Bainbridge added that secondary tooling is meant to enhance the core tooling, and you can add and customize the selection specifically to applications. It’s essential to tailor the grade and insert chipbreaker to the material.

“Once you have that, you can make any part you want,” said Bainbridge.

Senior Editor/Digital Editor Lindsay Luminoso can be reached at [email protected].

GenSwiss, genswiss.com

KYOCERA Precision Tools, www.kyoceraprecisiontools.com

Tungaloy, tungaloy.com/ca