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      <title>Follow Periphery</title>
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      <div class="title_topic3" id="xps10_pagetitle">Follow Periphery</div>
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      <p class="para_topic">Follow Periphery creates a cut pattern that produces a sequence of concentric passes following the contours of the cut region. The cut pattern will be generated by offsetting the peripheral loop of the region. When passes are overlapped with the inner shapes of the region, they will be merged to form one pass which then will be offset again to form the next pass. All passes within the machinable region will be closed shapes.</p>
      <p class="para_topic">Like Zig-Zag, Follow Periphery maximizes cutting moves by allowing the tool to remain continually engaged during stepovers. In addition to specifying the cut direction as Climb or Conventional, the Pocket Direction must be specified as Inward or Outward.</p>
      <p class="para_topic">The following figure illustrates the basic sequence of Follow Periphery tool movements using a Climb cut and an Outward pocket direction.</p>
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         <p align="center"><img align="bottom" src="graphics/pcmill_figurespl39.gif"></p>
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      <div class="title_figure">Follow Periphery - Climb, Outward</div>
      <p class="para_topic">When using an Inward pocket direction, the side of the tool nearest the center of the cut pattern determines Climb or Conventional. When using an Outward pocket direction, the side of the tool nearest the edge of the cut region determines Climb or Conventional.</p>
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         <p align="center"><img align="bottom" src="graphics/pcmill_figurespl38.gif"></p>
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      <div class="title_figure"> Follow Periphery, Climb</div>
      <p class="para_topic">The above figure illustrates how a Climb cut when used in combination with an Inward pocket direction produces a Conventional cut along the wall on the first pass. To avoid this, you can add  <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgmilling/com_millop_part_stock.html');return(false);">Part Stock</a> to move the first pass away from the wall and then specify a Finish Pass. The Finish Pass will produce a final profile cut along the wall to remove the Part Stock and maintain the specified Climb cut.
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      <p class="para_topic">Tool Paths do not cross one another. In cases where one area requires more pocketing passes than another area, the tool traverses between the subregions to complete the larger area as illustrated below. If many traversals are required, Region Connection can be used to optimize the tool motion.</p>
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         <p align="center"><img align="bottom" src="graphics/pcmill_cutat04.gif"></p>
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      <div class="title_figure"> Subregions</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: Whenever the stepover is very large (stepover&gt;50% of the tool diameter, but &lt;100% of the tool diameter) some areas may not be cut between consecutive passes. For these areas, the processor will generate additional cleanup moves to remove the material.</p>
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      <p class="para_topic">Diagonal tool movements called tusks are generated at the corners of inner passes to remove material from corners. Tusks become necessary when the stepover is large in relation to the tool diameter and there is no overlap between passes at the corners.</p>
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         <p align="center"><img align="bottom" src="graphics/pcmill_figurespl37.gif"></p>
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      <div class="title_figure">Tusks</div>
      <div class="title_division">Skinny Regions</div>
      <p class="para_division">The system recognizes that Follow Periphery cut pattern does not fit in skinny regions. &nbsp;Therefore, when you use Follow Periphery with skinny regions, the system automatically adjusts the cut pattern to allow for a profile pass along the skinny region. &nbsp;Notice in the figure below that the Follow Periphery cut pattern (number 4) is placed further down on the part; it does not follow the entire part. &nbsp;This is because the final profile pass (number 2) machines the remaining material. &nbsp;This eliminates wasted movements as a result of cutting air (material already cut by the previous Follow Periphery pattern). &nbsp;</p>
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         <p align="center"><img align="bottom" src="graphics/fol_periph_skinny.gif"></p>
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      <div class="title_figure">Follow Periphery with Skinny Regions</div>
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               <p class="para_td">1</p>
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               <p class="para_td">&nbsp;The part is represented by the green area.</p>
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               <p class="para_td">2</p>
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               <p class="para_td">Final Profile pass to cut skinny region, as well as area not cut by Follow Periphery path, represented by straight blue line.</p>
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               <p class="para_td">3</p>
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               <p class="para_td">Cut Region represented by dashed pink line.</p>
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               <p class="para_td">4</p>
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               <p class="para_td">Follow Periphery represented by light blue path.</p>
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               <p class="para_td">5</p>
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               <p class="para_td">Area not cut by Follow Periphery path represented by the brown area.</p>
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      </table><br><div class="title_division">Cut Order</div>
      <p class="para_division">For inward progression, the system cuts all the open passes first, and then cuts all the closed inner passes. &nbsp;For outward progression, the system cuts all the closed inner passes first, and then cuts all the open passes. &nbsp;When cutting the open passes, the tool engages to an open pass, cuts, retracts and transfers to another open pass.</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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               <div class="para_note">
                  <p class="para_note_body">Follow Periphery with skinny regions is new behavior. &nbsp;Prior to NX2, when using Follow Periphery pattern, you had to turn on Wall Cleanup and Island Cleanup to machine narrow regions that may not have been cut.</p>
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