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      <title>Extend at Edges</title>
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      <div class="title_topic3" id="xps10_pagetitle">Extend at Edges</div>
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      <p class="para_topic">Use Extend at Edges to machine excess casting material around the part. &nbsp;You also can use it to add cutting moves to the start and end of tool path passes to ensure that the tool smoothly enters and exits the part. &nbsp;</p>
      <p class="para_topic">You can find Extend at Edges on the Cutting Parameters dialog for Flowcut, Area Mill, and Zlevel Profile operations.</p>
      <p class="para_topic">The tool paths are extended tangentially past all the external edges of the cut area, as in the figure below. &nbsp;</p>
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         <p align="center"><img align="bottom" src="graphics/dsply_extend_pth.gif"></p>
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      <div class="title_figure">Extension surface around the top of the part</div>
      <p class="para_topic">Notice in the figure above that the edges are extended along the sides of the part, as well as at the start and end of the tool path. </p>
      <p class="para_topic">Extend at Edges eliminates the time consuming, and tedious, task of trying to generate ribbon surfaces around the part to achieve the same functionality. &nbsp;The system determines where the edges are, based on the selected cut area. &nbsp;Therefore, if you choose a solid without a cut area, there are no edges to extend. &nbsp;</p>
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         <li>
            <p class="para_item">To temporarily see the extension surfaces, display the cut area from the operation dialog immediately after generating the toolpath. </p>
            <p class="para_item">The following graphic illustrates the resulting area mill tool path:</p>
            <div class="figure">
               <p align="center"><img align="bottom" src="graphics/extend_edge.gif"></p>
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            <div class="title_figure">Resulting tool path with extended surface</div>
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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">The extension surfaces in these figures are generated to illustrate the extension of the tool paths. &nbsp;No surface graphics are generated when this option is used. &nbsp;Only the extended tool path(s) is generated. </p>
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      <div class="title_division">Limitations</div>
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            <p class="para_item">Cut levels in Zlevel Profile do not reflect the tangent extension surfaces if they lie outside the indicated levels. &nbsp;You must manually adjust the cut level range in this situation.</p>
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         <li>
            <p class="para_item">The part offset or stock of the first piece of part geometry is used for all of the extensions.</p>
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            <p class="para_item">If the extension surfaces extend beyond the bounds of the specified cut levels, no cuts are generated outside of those cut level values, as illustrated below. &nbsp;</p>
            <div class="figure">
               <p align="center"><img align="bottom" src="graphics/extend1.gif"></p>
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            <div class="title_figure">Original Zlevel path with no extensions</div>
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      <p class="para_division">In the figure below, the edges are extended. &nbsp;However, note that there are no cuts above the top of the part because this would be outside of the range of the cut levels. &nbsp;This indicates that you must increase the cut level range even further. </p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/extend2.gif"></p>
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      <div class="title_figure">Zlevel path with extensions, but no cut level adjustment</div>
      <p class="para_division">To cut the extensions above the part, you must manually adjust the cut level range, raising the top level. &nbsp;In the figure below, the top level of the cut range has been raised above the top of the part so that cuts are generated above the extensions. &nbsp;</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/extend3.gif"></p>
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      <div class="title_figure">Extensions with expanded cut level range</div>
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            <p class="para_item">Selection of edges</p>
            <p class="para_item">The system applies tangent extensions to all external edges, and only external edges. The control is limited to the use of cut area and trim regions. &nbsp;When solid part geometry is used with no cut area, there are no external edges. In this case, you need to select a cut area. </p>
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            <p class="para_item">Overlap of extensions from different edges</p>
            <p class="para_item">If the hole diameter is less than the extension length, then the extension surface will interfere with the part surface on the other side of the hole. The system resolves this situation for holes (see the figure below), but not for adjacent peripheries. &nbsp;If the jumps in tool path are unacceptable, then you may have to use the tool path editor. &nbsp;</p>
            <div class="figure">
               <p align="center"><img align="bottom" src="graphics/extnd_holes.gif"></p>
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            <div class="title_figure">If the part has internal holes, then the extensions may completely cover them. &nbsp;</div>
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         <li>
            <p class="para_item">Maximum extension length</p>
            <p class="para_item">The extension length is limited to 10 times the tool diameter.</p>
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