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      <title>Set Trim Angles</title>
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      <div class="title_topic3" id="xps10_pagetitle">Set Trim Angles</div>
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      <table base="file:///D:/perforce/workdocs/XPS/products/nx/nx5/english/tdoc/mfgturning/entities/turn_cont_trim_angles.xml" bgcolor="#f4f4f4" cellspacing="0" width="100%" align="center">
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            <td colspan="1" rowspan="1" width="25%">
               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/turn_cont_trim_planes2.html');return(false);">Setting Trim Planes</a></p>
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               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/04topic_14.html');return(false);">Setting Trim Points</a></p>
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            <td colspan="1" rowspan="1" width="25%">
               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/turn_cont_comb_point_plane.html');return(false);">Combining Trim Point &amp; Trim Plane Containment</a></p>
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               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/turn_cont_dial_opt2.html');return(false);">Containment Dialog Options</a></p>
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      </table><br><p class="para_topic">A trim angle is the polar angle of a vector pointing in the direction of a half-ray that connects the part to the blank boundary at each trim point. In the case where two trim points are selected, the points of intersection of these two resulting half-rays with the blank boundary will mathematically define the cut region. Cutting is guided along these half rays towards the trim point at the beginning or away from the trim point at the end of the portion of the boundary to be contained. This provides directional control of the motions that are necessary to cut to the trim point through the blank material and of those necessary to leave the part boundary through the blank at a trim point. The system will take into consideration any stock value that may be specified for blank or part. If the trim angle corresponds to the tangent angle of the segment on which the trim point lies, the cutting continues smoothly beyond or towards the part boundary. This behavior is illustrated in the next figure:</p>
      <p align="center"><img align="bottom" src="graphics/trim_angles.gif"></p>
      <table base="file:///D:/perforce/workdocs/XPS/products/nx/nx5/english/tdoc/mfgturning/entities/turn_cont_trim_angles.xml" bgcolor="#f4f4f4" cellspacing="0" width="100%" align="center">
         <tr valign="top">
            <td colspan="1" rowspan="1" width="25%">
               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/turn_cont_trim_planes2.html');return(false);">Setting Trim Planes</a></p>
            </td>
            <td colspan="1" rowspan="1" width="25%">
               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/04topic_14.html');return(false);">Setting Trim Points</a></p>
            </td>
            <td colspan="1" rowspan="1" width="25%">
               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/turn_cont_comb_point_plane.html');return(false);">Combining Trim Point &amp; Trim Plane Containment</a></p>
            </td>
            <td colspan="1" rowspan="1" width="25%">
               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/turn_cont_dial_opt2.html');return(false);">Containment Dialog Options</a></p>
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      </table><br><p class="para_topic">A trim angle is the polar angle of a vector pointing in the direction of a half-ray that connects the part to the blank boundary at each trim point. In the case where two trim points are selected, the points of intersection of these two resulting half-rays with the blank boundary will mathematically define the cut region. Cutting is guided along these half rays towards the trim point at the beginning or away from the trim point at the end of the portion of the boundary to be contained. This provides directional control of the motions that are necessary to cut to the trim point through the blank material and of those necessary to leave the part boundary through the blank at a trim point. The system will take into consideration any stock value that may be specified for blank or part. If the trim angle corresponds to the tangent angle of the segment on which the trim point lies, the cutting continues smoothly beyond or towards the part boundary. This behavior is illustrated in the next figure:</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/trim_angles.gif"></p>
      </div>
      <div class="title_figure">Trim Angles Aligned with the Groove's Chamfers, Corresponding Trim Points Shown in Red, Blank Boundary in Orange</div>
      <p class="para_topic">To see the effect of setting trim angles, consider the following situation. You want to remove the remaining material at the bottom of a groove. In order for the system to recognize the material, you have to set a trim point at the bottom of the groove  <img align="bottom" src="graphics/num_1.gif" border="0">. As the half ray resulting from the trim angle is automatically extended tangentially to the cutting line  <img align="bottom" src="graphics/num_2.gif" border="0">, setting only a trim point would result in the system recognizing all material lying above the half ray  <img align="bottom" src="graphics/num_3.gif" border="0"> as needing to be cut. This would ruin the part. Internally, the system acknowledges this situation and ignores the trim points. This, too, is undesirable as it would then not recognize any cut region (see  <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/04topic_14.html');return(false);">Setting Trim Points</a> for more details). 
      </p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/trim_angles_a.gif"></p>
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      <div class="title_figure">Trim Points with no Trim Angles</div>
      <p class="para_topic">To cut this remaining material, you need to set trim points and trim angles. In this example, we set a trim angle of 70  <img align="bottom" src="graphics/num_4.gif" border="0"> which ensures that the remaining material is detected as a cut region while still protecting the workpiece.
      </p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/trim_angles_b.gif"></p>
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      <div class="title_figure">Correctly Set Trim Points and Trim Angle</div>
      <div class="title_division">Angle Offset</div>
      <p class="para_division">Use Angle Offset to alter the trim angle, but still keep the angle associative to the selected geometry.</p>
      <div class="title_division"> Setting Trim Angles:</div>
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         <li>
            <p class="para_item"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/turn_cont_dial_opt2.html');return(false);">Open the Containment dialog</a>.
            </p>
         </li>
         <li>
            <p class="para_item"> <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgturning/04topic_14.html');return(false);">Select trim points</a>.
            </p>
         </li>
         <li>
            <p class="para_item">Select angle check box for that trim point.</p>
         </li>
         <li>
            <p class="para_item">If desired, select angle offset. The angle is measured in a counterclockwise direction.</p>
         </li>
      </ol>
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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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               <div class="para_note">
                  <p class="para_note_body">Non&ndash;zero trim angles may affect which faces or corners of your part can be reached with cutting moves </p>
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