Sculpting Product Development Cycles With CAM

Agile CAM software helps dental equipment manufacturer get to market faster with better organically designed products.

Producing patterns and part prototypes used to be a bottleneck in the product development cycle for A-dec (Newburg, Oregon), America’s largest dental equipment company. That is not the case anymore. Components that used to take several weeks for evaluation are now routinely produced in a week or less and the manufactured piece almost always represents a more faithful representation of the design intent.

The transition to a more agile response for product development parts began seven years ago when the company decided that it would replace the CAM software it was using for production machining with a product that was easy to learn, use, and cleanly imported a broad range of CAD files. Senior Model Maker, Ken Chamberlain said that Mastercam Version 8 was chosen and that the software, now Mastercam X, has grown to eight seats used both in the product development and toolmaking departments.

Chamberlain explained that A-dec has a three tiered design process for new products. First, he programs his CNCs to make parts or patterns for look-and-feel evaluations of the design. The next round of developmental manufacturing is for structural assessment. In the final round, the A-dec product development team evaluates the new product design for aesthetics, overall functionality, and structural integrity. As the due date for one of these development reviews draws nearer, the pace of work to meet the deadline seems to grow exponentially.

Responding to Changes

A-dec’s Supervisor of Engineering Services, Ken Dana, cited the company’s market leading dental chairs as an example of products with agile responsiveness to design modifications. He said the company is pushing the envelope with Euro designs featuring numerous precise (i.e. sculptured) surfaces for patient comfort and lots of open space to provide better access and working comfort for dentists and their assistants. The chairs have about 50 components that are thoroughly designed for functionality, structural integrity, aesthetics, and manufacturability. The review process for dental chairs ultimately involves about 30 people representing engineering, marketing, and manufacturing at A-dec.

When a product like this is in one of its evaluation phases, CAM programmers like Chamberlain work non-stop to produce patterns and parts for the new design modifications. Chamberlain, who is responsible for making parts on a Fadal and a Mori Seiki vertical mill, works with Mastercam using two monitors to give himself a larger work area. Sometimes he actually needs both monitors for programming two parts simultaneously to keep the process moving.

Within the past year, A-dec has upgraded its Mastercam licenses to X2, which includes an interface that Chamberlain can customize to put all the tools he routinely uses within easy reach and a suite of high-speed toolpaths that not only improve manufacturing productivity on the mills but also allows Chamberlain to produce high fidelity parts with smooth seamless transitions that nearly duplicate the 3D CAD model. Chamberlain said that when he made the switch from Mastercam 9 to X the software was so different he went through an awkward state that lasted about a week. After that, he never looked back.

Features of the CAM software that help Chamberlain respond expeditiously to design modifications include:

Sculpting Surfaces: In the past, A-dec would make wooden patterns of its sculptured chair components. When the curves in the design were changed it could take weeks to get a new pattern that would not always reflect what the designer had in mind. Now the prototype components are cut from wood or aluminium and alterations to the sculptured surfaces are made easily.

Overlaying Toolpaths: Chamberlain said, “With each developmental milestone, the product becomes a little more complete and a little bit more intricate. Often, I’ll keep the old file and lay the new one right on top. The program is already there. I just recreate the toolpath. That saves a lot of time as opposed to starting a whole new session of Mastercam and selecting new tools, starting from scratch. A lot of times I will use the same operation but I’ll just change the geometry. That also saves a lot of time.”

Surface Blending: Chamberlain said, “With the sculptured surfaces you are not dealing with the perpendicular or parallel surfaces, you are blending one curved radius into another curved radius and possibly into a third. So it’s tremendously difficult to create. Not all softwares out there are able to do those kinds of shapes well. However, Mastercam provides tools that allow surfaces to blend into seamless curves.”

Eliminating Secondary Operations: Precise control of the toolpaths, especially at the transitions, makes it possible to eliminate secondary operations like polishing of molds or sanding of castings. Not only does this save time, but also in the case of the castings provides better structural integrity because excessive sanding can degrade the model.

High-Speed Savings: Time and dollar savings also accrue once the CNC equipment begins manufacturing the new part design. “The high-speed toolpaths are just awesome,” said Chamberlain. “I use them all the time. Two things happen – I get more time with the tool cutting as opposed to air moves.” (Chamberlain has no data but he thinks his CNC machines are producing parts about 25% faster using the high-speed toolpaths.) “And I have also noticed better tool life because the CNC toolpaths make smoother transitions in and out of the cut.”

Bottom Line

The switch to agile, user-friendly CAD software has reduced product development part manufacturing costs. More importantly, it has given A-dec the ability to reproduce components that more faithfully represent the changes, even intricate ones, that have been made in the CAD model. Organic surfaces that could not be produced with CNC equipment previously have now become a reality because of newfound control over the toolpaths.

Finally, the turn-around time for evaluation parts for product development has been substantially reduced. Dana believes that a 20% reduction would be a conservative estimate. As a result, the manufacturing of design modifications are rarely, if ever, bottlenecks in A-dec’s product development cycles.