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      <title>Projection Vector</title>
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      <div class="title_topic3" id="xps10_pagetitle">Projection Vector</div>
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      <p class="para_topic">Projection Vector enables you to define how the Drive Points project to the Part Surface, and the side of the Part Surface the tool contacts.</p>
      <p class="para_topic">The Drive Points project along the Projection Vector to the Part Surface. Sometimes, as illustrated below, Drive Point project in the opposite direction of the Projection Vector (but still along the vector axis) as they move from the Drive Surface to the Part Surface.</p>
      <p class="para_topic">The direction of the Projection Vector determines the side of the Part Surface the tool contacts. The tool always positions to the Part Surface from the side the Projection Vector approaches. In tne following figure, drive point p1 projects to the Part Surface in the opposite direction of the Projection Vector to create p2.</p>
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         <p align="center"><img align="bottom" src="graphics/drvpt_proj_ptsurf.gif"></p>
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      <div class="title_figure">Drive Point Projects to Part Surface</div>
      <p class="para_topic">The types of Projection Vectors available depend upon the Drive Method. The Projection Vector option is common to all Drive Methods except Flow Cut.</p>
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            <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
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                  <p class="para_note_body"> NOTE: Care should be used when selecting a Projection Vector to avoid situations where the Projection Vector is parallel to the Tool Axis Vector or is perpendicular to the Part Surface normal. These situations can result in vertical oscillations in the toolpath.</p>
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      <p class="para_topic">The following figure illustrates another example of how the Drive Points project to the Part Surface. In this example, the Projection Vector is defined as Fixed. The vector is parallel to the ZM axis at any given point on the Part Surface. To reach the Part Surface, the Drive Points must project from the Boundary Plane in the same direction as the Projection Vector arrowhead.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/drv_same_projvec.gif"></p>
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      <div class="title_figure">Drive Path Projects in the Same Direction as Projection Vector</div>
      <p class="para_topic">The direction of the Projection Vector determines the side of the Part Surfaces the tool contacts.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/projvec_toolside.gif"></p>
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      <div class="title_figure">Projection Vector Determines the Tool Side of Part Surface</div>
      <p class="para_topic">The following figures illustrate how the direction of the Projection Vector determines which side of the Part Surfaces the tool contacts. In each figure, the tool contacts the same Part Surface (inside the cylinder), but the contact side differs depending on the direction of the Projection Vector.</p>
      <p class="para_topic">The Projection Vector illustrated below, Towards Line, yields undesirable results. The tool follows the direction of the Projection Vector and approaches the Part Surface from the outside of the cylinder and gouges the part.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/twdln_projvec.gif"></p>
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      <div class="title_figure">Towards Line Projection Vector</div>
      <p class="para_topic">The Projection Vector illustrated below, Away From Line, yields the desired results. The tool follows the direction of the Projection Vector and approaches the Part Surface from the inside of the cylinder and does not gouge the part.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/awyln_projvec.gif"></p>
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      <div class="title_figure">Away From Line Projection Vector</div>
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            <td valign="top" align="left"><img align="left" src="../graphics/warning.gif" alt="Warning" title="Warning"></td>
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                  <p class="para_warning_body">CAUTION: When using Away From Point or Away From Line as the Projection vector, the minimum distance from the Part Surface to the vector focal point or line must be greater than the radius of the tool as illustrated below. The tool end must be allowed to position to the projection vector focal point or anywhere along the projection vector focal line without gouging the Part Surface.</p>
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      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/nogouge.gif"></p>
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      <div class="title_figure">Tool Does Not Gouge Part Surface</div>
      <p class="para_topic">If the tool gouges the Part Surface when the tool end is positioned at the focal point or anywhere along the focal line as illustrated below, the system cannot guarantee a good tool path.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/gouge_projvecfocln.gif"></p>
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      <div class="title_figure">Tool Gouges Part Surface when Positioned at the Projection Vector Focal Line</div>
      <p class="para_topic">The following options allow you to define the Projection Vector.</p>
      <p align="center"><img align="bottom" src="graphics/projvectr.gif"></p>
      <p class="para_topic">Normal to Drive is only available when using the Surface Area Drive Method.</p>
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            <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
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                  <p class="para_note_body"> NOTE: The Verify Projection Vector option is no longer available. To verify an existing Projection Vector, simply select the same Projection Vector option used in the current operation to display the values defining the vector.</p>
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      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/xyzfocalpt.gif"></p>
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      <div class="title_figure">Towards Point Yields the X,Y,Z Coordinates of the Focal Point</div>
      <p class="para_topic">Some Projection Vectors such as Normal To Drive Surface are independent of points and lines, and will not yield any verification information.</p>
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