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Technical Section Phone: 516-328-3970 www.technocnc.com  23 CAD / CAM & CNC Software CAD and CAM software packages are closely related to one another. In fact, they share the first two thirds of their respective  acronyms:  CAD  /  CAM  stand  for  Computer- Aided  Design  and  Computer-Aided  Manufacturing.  CAD programs typically are used to draw thepartbeingdeveloped. CAM programs are used for generating the toolpath for the CNC machine that will cut the part. The boundary between the two programs is often blurred as CAM programs often have drawing capabilities and CAD programs often have “plug in” programs, or added optional features, that allow them to generate toolpaths. CAD/CAM programs get installed on a computer and, contrary to popular belief, learning to navigate the various functions  is  not  rocket  science.  At  first,  the  different  file formats and industry terms can be overwhelming. The good news is that with each successive completion of the cycle, from  drawing,  to  toolpath,  to  cutting  a  part,  the  method becomes  more  familiar  and,  subsequently,  easier  to reproduce. CAD software creates drawings in 2D or 3D formats. Traditionally, CAD programs were primarily for engineering drawings and drafting. Its usefulness has evolved beyond the tasks of precise dimensioning. Expanded capabilities now include realistic renderings, dynamic analysis of moving elements and various finite element engineering analyses. A few standard 2D formats include: .DWG, .DXF, and .EPS.  2D CAD files typically share the same graphical element  in  that  they  are  vector-based.  Vector  graphics consist of lines, arcs and other elements, in contrast to the pixels that make up a raster file, like a digital photo. Vector graphics define these lines, arcs and polylines with simple mathematical  equations.  3D  CAD  files  are  similar,  but much  more  complex.  Hundreds  and  even  thousands  of facets are calculated when creating 3D CAD files such as, .STL, .3DS, and .RAW. This is just a sampling of some of the  more  standard  formats  specific  to  different  CAD programs. Other formats, such as .IGS, define 3D surfaces and lines using complex parametric equations. CAM  software  helps  convert  and  manipulate  a  CAD drawing  into  a  toolpath.    CAM  software  imports  a  CAD drawing and saves it in its own native file format. There are some programs that have both CAD and CAM capabilities in one software package, which is a convenient feature, but the transfer of files between two separate and standard CAD / CAM programs is not complicated. In fact, most CAD and CAM programs have built-in capabilities to both import and export several file formats. The toolpath generated by most CAM programs is in a standard manufacturing programming language called G- Code. Consisting of “G” and “M” codes or commands, a G- Code file guides the path of the cutter through the material by  outputting  code  for  linear  or  circular  motions.  CAM software also embeds parameters into the G-Code, such as tool width, toolpath position, cut depth, feeds and speeds, and others. These CAM parameters become increasingly important as the files being cut become more complex. For exhaust port. The main drawback of using a cold air gun is that a fairly large compressor is required. This need for a substantial compressor does add to the overall cost of the unit.