Bridging the CAM-to-machine gap

When people ask why it’s important to select a high-quality post-processor, I always liken it to building a house. The builder creates the foundation and frame but often relies on other suppliers for the finishing work—everything from flooring to painting to siding. The resulting work often varies in quality, with multiple contracts and several warranties. Unfortunately, there is no one-stop shop for building a home.

The process is often similar for owners of machine tools, who must rely on a third party for post-processor development. Typically, end users are forced to purchase machine tools and CAM and post-processing software from different suppliers, leading to discrepancies in quality, thoroughness and delivery. Furthermore, the CAM-generated program may not run successfully on the machine tool, creating a bottleneck.

Post-processors for machine tools are analogous to drivers for computer printers, where a different driver is required for printers from various manufacturers and for each computer operating system. This is called many-to-many mapping, meaning a printer must have a driver for every operating system and every operating system must support every printer. Similarly, a post-processor translates CAM-dependent solid models and cutter toolpaths into the G and M code that a machine tool understands.

Every CNC machine tool is unique because of its controller and axis configurations, and each CAM program is different because of its proprietary toolpath generation and internal data storage format. The post-processor is a module that bridges the gap between the software and machine.

Courtesy of DMG / Mori Seiki USA

Work flow of the Manufacturing Suite post-processor from DMG / Mori Seiki.

Without a high-quality post-processor, the CAM software and machine tool can’t communicate properly. The challenge lies in the current post-processor delivery model. CAM developers—who may not have the best knowledge about machine tools—create the post-processors. Therefore, to assist in the arduous process of developing reliable post-processors, they approach machine tool builders. This post development for each CAM developer is repeated many times by the machine tool builders, and for each machine tool make and brand by the CAM developer, leading to wasted resources for both CAM developers and machine tool builders.

But what if there was one contact for post development? It would likely simplify and expedite the process. This is precisely why machine tool builder DMG / Mori Seiki created the Manufacturing Suite post-processor (MSPP). The new post-processor is part of a simple and integrated suite of applications called Manufacturing Suite, which provides a user-friendly interface in a compact package. It can dramatically shorten the learning curve associated with traditional post-processors.

This universal post-processor will be available in October for all Mori Seiki machines and will work with any CAM software that outputs toolpaths in Mori-APT (automatically programmed tool) standardized format. MSPP software comes with post templates to output NC code for all Mori Seiki machines.

In a related development, my team at DMG / Mori Seiki developed a template-based post-processor for MAPPS (Mori Seiki Advanced Programming Production System). The result is Mori-Post, which features a generic Mori-APT-formatted, toolpath-input interface that any third party can leverage. This means anyone using the interface can generate NC code instead of using a CAM-dependent post-processor. The Mori-APT toolpath format is an extension of the APT CLDATA (cutter location data) standard, which is based on ANSI NCITS 37-1999 and ISO 4343:2000. Mori-Post is included in Manufacturing Suite. In addition, the Mori-APT interface is available to CAM suppliers so they can utilize the post-processors developed by Mori Seiki.

Returning to MSPP, it can import the standardized toolpath from any CAM software program and generate NC code using DMG / Mori Seiki post templates. For the process to work, end users need to acquire the Mori-APT CLDATA interface-enabled version of the CAM software from their respective CAM suppliers and acquire the MSPP software from DMG/Mori Seiki.

The advantages of MSPP extend beyond the post-processor itself. The Manufacturing Suite software is a bundle of applications tightly integrated with one another and with the machine tools. Because this is a new and potentially disruptive concept, it may take some time to catch on. However, with the constant frustrations that post-processors bring, it shouldn’t take long.CTE