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S O F T W A R E T HE TRANSITION FROM 2D CAD TO 3D CAD is not just another software upgrade. It requires the user to move from the world of 2D drafting to the world of 3D modeling. More than making 3D drawings, 3D CAD is about mak- ing models from which a wide range of information products can be generated. The laundry list of benefits 3D CAD ven- dors and experts talk about when promoting the migration to 3D CAD is almost exclusively focused on product design and development areas where machinists rarely get to ven- ture other than to inform engineers that their part cannot be made as designed. But 3D CAD is just as powerful a tool on the shop floor as it is in the engineering office. How many times has a machinist (or CNC programmer) looked at a 2D drawing from a customer and found that one or more critical machining measurements are missing? The designer either didnt know those specific measurements were needed, or the designer simply forgot to note them, so 26I AMERICAN MACHINIST I APRIL 2007 I 3DCAD has become a“must have” Migrating from 2D to 3D CAD takes time but the payback is worth it. B Y L A W R E N C E H A F T L I ASSOCIATE EDITOR 3D CAD models provide a wide array of information about a product. I APRIL 2007 I AMERICAN MACHINIST I 27 the machinist has to stop working and contact the customer for those necessary dimensions. Or how many times has the machinist been given a 2D drawing with a revision on it and not been able to see or was not informed about the impact that the revision would have on other areas of that part or on other related parts? Much of the power of 3D modeling lies in its associative ability. Change one dimen- sion on one part, and everything related to that dimension gets changed immediately and appropriately. If the customer supplies the ma- chinist with a 3D model instead of, or in addition to, whatever other drawings they normally supply, then the machinist can get the required measurements right from the model. If there is a revised model, the ma- chinist can see everything impacted by that revision. The machinist does not have to be a 3D CAD modeling guru to do this, because it is easier to view and interrogate a 3D model than it is to create the model. The moneymaking software in a machine shop is the CAM package(s) the shop uses to convert customer de- signs into the executable g- and m- codes that are used to run their CNC machines. CAM packages are inher- ently 3D based, so it is more efficient to go from a 3D CAD model to CAM than it is to start with a 2D drawing. Software vendors recognize this bene- fit can be a major selling point and so they are all working toward, or have achieved, a smooth transition from designing a part using 3D CAD func- tions to making the part using the CAM functions. CAM vendors such as EdgeCAM, Esprit, FeatureCAM, GibbsCAM, MasterCAM, Smart- CAM and SolidCAM now offer close integration to the two most popular stand-alone 3D CAD products: Au- todesks Inventor, and SolidWorks. Other software packages such as Catia, Cimatron, Delcam PowerX, Pro/Engineer, Unigraphics and VX go one step further by offering fully integrated 3D CAD/CAM function- ality in a single package. Both compatible and fully-inte- grated packages provide machine shops with at least two competitive advantages: reduced time to go from customer order to cutting metal; and reduced miscommunication that might otherwise result in excessive scrap, rework and customer dissatis- faction. The reductions in time and machining costs are proving so sig- w w w . a m i n f o . b i z / 0 4 7 . a d nificant that machine shops not working in 3D may lose their ability to compete in the marketplace altogether. More than one company has admitted to realizing they would be out of business within five years or less if they did not make the transition to 3D modeling. Why havent all companies switched from working with 2D drawings to working with 3D models? The migration is not easy. Many companies that successfully migrated found that the best approach is to train their people to start working 28I AMERICAN MACHINIST I APRIL 2007 I S O F T W A R E solely in 3D, and dont spend time con- verting any of the existing 2D work to 3D unless there is a compelling and im- mediate demand. The chances of a smooth and timely implementation are increased if you do the following: Provide top management with at least a conceptual understanding of what 3D modeling is all about, how it works and why the company should be using it. Keep all employees that will use or be affected by the new software fully informed. Ask for their input. Meetings should include managers and employees. When looking at equipment needs, also look at possibly using some of the new input devices for ad- ditional productivity gains. Consider the possible benefit of having a single person or team dedi- cated to ensuring the implementation goes smoothly. Create a comprehensive checklist before you start the implementation. Your software vendor can help here and should be able to connect you to some of their other customers who have had suc- cessful implementations. Dont hesitate to learn from the mistakes of others. Create a schedule of key targets in the implementation and stick to it as closely as possible. Create standards and procedures initially, but remain flexible enough to modify them as needs arise. Keep all documentation printed and electronic up-to-date. Implement modules in a logical and progressive way so that all of the users can understand and internalize the whole package. Several companies that succeeded in going from 2D to 3D said that while the basics of the soft- ware took a month or so for employees to learn to use, full familiarity and comfort with the new software took employees, on average, about a year. Hold ongoing reviews to identify opportunities as well as problems. Most machine shops know that se- lecting a 3D CAD or fully integrated 3D CAD/CAM package is up to their customers. Many of the CAM pack- ages claim complete compatibility with all of the usual 3D model formats, but recent surveys say serious incompati- bilities still exist that may force the complete rebuilding of the model in the CAM package. Before investing in