Think like a machinist

Feb. 7, 2022
Conversational programming streamlines and simplifies machining parts

For more than half of the workpieces that shops machine, conversational programming not only streamlines and simplifies the transition from print to part, it makes that process accessible to an entirely new population of operators with less-than-expert levels of knowledge.

Because of the scarcity of skilled programmers and machinists, shops need every advantage that can help them to produce parts quickly and efficiently, to minimize programming needs and to avoid damaging crashes.

Also read: Greater return on CNC

Machine tools began to feature conversational programming so operators could program parts on their machines without having to learn G-code or rely on the advanced knowledge of programmers for every job. Just as an experienced machinist understands how to set up a job, conversational-programming systems ask for structured input and use it to cut parts successfully. Behind the scenes, extensive information about the behavior of materials, cutting tools and part geometry bridges the gap between part specs and machining results.

An effective conversational-programming platform builds the insights and methodical approach of an experienced machinist directly into a touch-sensitive CNC, so new and young operators can accomplish complex tasks without lengthy training. These features also enable shops to avoid time-consuming, error-prone manual entry of tool and part parameters.

The end results are faster part production, better parts and higher machine utilization, coupled with a practical approach to overcoming the manufacturing skills gap.

In industries such as aerospace, complex geometries such as contoured five-axis parts, 3D modeling or 3D surfacing may exceed the capabilities of even the most advanced conversational programming systems because of the sheer volume of code required to produce their features.

Conversational programming combines speed with accuracy and convenience for the simpler aspects of these complex workpieces and for cutting strategies such as trochoidal milling of prismatic parts, which makes up perhaps 95% of a typical job shop's workflow.

The convenience of conversational programming starts with a logical sequence of questions designed to define all aspects of the manufacturing task. A customer's print specifies the features of the part, which in turn determine the cutting tools required to produce it. Through the conversational input process, the operator chooses individual processes to make each feature of the part. As the conversational system builds out the program piece by piece, it displays a 3D model that makes it easy to identify mistakes, correct them and verify that the onscreen result matches the blueprint.

The ability to reorganize processes helps to prioritize as well as optimize a conversational program. Ideally, conversational programming treats individual machining sequences as building blocks of activity that the operator combines and reorganizes as necessary.

If a unit of the program winds up out of sequence, the operator can shuffle the modular building blocks to put them in the proper sequence, rather than having to backtrack and change the order of individual steps.

The conversational approach significantly simplifies otherwise-complex setup tasks. Automatic calculation of positions translates the entry of basic parameters into a completed part profile. Once an operator identifies the material and cutting tools for a part, additional automatic calculations set up appropriate speeds and feeds.

Advanced conversational programming systems can import a model output from a CAD system, calculate axis points and build the rest of the program once the operator identifies relevant features.

In addition to extrapolating complete sets of programming steps from simple input, conversational programming also can perform a 3D simulation of the cut to verify the code it writes. Any risk of crash or collision instantly shows up in the simulation for immediate correction, and, once the verification completes, the resulting program carries a high confidence level. This validation speeds job changeovers and makes it possible to cut parts correctly the first time.

In high-mix, low volume (HMLV) production environments, with jobs that can consist of a single high-value part made from expensive materials, this type of assurance can save a shop from costly catastrophes.

Ideally, a machine-tool manufacturer evolves the capabilities of its conversational programming so new features ride on the foundation that built the success of the system. This enables operators to move seamlessly from an older generation of controls to a newer one without losing access to familiar procedures. Unfortunately, some manufacturers fail to carry forward previous capabilities, leaving operators to learn an entirely new system rather than to add new functions to their existing understanding.

Flexibility is a hallmark of excellence in conversational programming. Not only do these systems enable operators to start with a blueprint, a 3D model or a hand-drawn sketch with a scribbled set of dimensions, but they also provide multiple ways to approach any given task.

The more intuitive the control and the system, the more readily operators can use it fluently. Continuous cycles of improvement and refinement enable these systems to grow in ease of use as well as in functional power.

Whereas a motivated machinist might need six months of study and practice to learn to write G-code programs, the same machinist could learn conversational programming in a week. The biggest difference between G-code or EIA/ISO and conversational programming equals the difference between learning an entire language and being able to translate intentions directly into functions.

G-code includes hundreds of numeric commands that a knowledgeable programmer can recognize and interpret. To the inexperienced eye, these codes look like nothing more than an endless list of real numbers. With conversational programming, operators can express their intent and translate it into code without having to learn the code system itself.

A well-designed conversational programming system not only provides value through the efficiency and productivity it offers, but it also offers a depth of functionality that remains valuable over time. Some machine tools do a good job of producing a specific type of part, but when new types of projects enter the picture, the machine struggles to keep up with additional challenges. With nothing more than a blueprint, truly advanced conversational programming can generate a program, process list or time study, and even set the part up for inspection so it emerges from the machine fully qualified and checked.

To make production easier for small to medium-sized shops and companies that struggle to find experienced operators, machine-tool manufacturers have invested decades of expertise and experience into conversational programming systems. Such a solid foundation and the innovations that enhance it give these tools productive power that makes these systems indispensable on the production line.

From HMLV output to the on-demand, just-in-time workflows that today's customers demand, conversational programming makes competitive success a confident reality. Instead of complex programming or hit-and-miss results, these systems empower shops to thrive on new types of parts, materials and expectations.

About the authors

Andy Watkins is sales application engineer at Knox Machinery in Hamilton, Ohio. Contact him at [email protected].

Samuel Patterson is applications engineer/manufacturing specialist at Knox Machinery. Contact him at [email protected].

About the Author

Andy Watkins | Contributing Editor

Andy Watkins is direct sales manager at Romi Machine Tools in Erlanger, Kentucky. Contact him at [email protected].