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      <title>Avoidance</title>
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      <div class="title_topic3" id="xps10_pagetitle">Avoidance</div>
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      <p class="para_topic">You may define the following avoidance geometry.</p>
      <ul>
         <li>
            <p class="para_item">From point</p>
         </li>
         <li>
            <p class="para_item">Start point</p>
         </li>
         <li>
            <p class="para_item">Return point</p>
         </li>
         <li>
            <p class="para_item">Go Home point</p>
         </li>
         <li>
            <p class="para_item">Clearance plane</p>
         </li>
      </ul>
      <p class="para_topic">You must specify a clearance plane.</p>
      <p class="para_topic">If you do not specify any of the avoidance points (i.e., From , Start , Return and Go home points), the clearance plane point computed will be set as the From , Start , Return and Gohome points. The Clearance Plane point is a point on the clearance plane along the thread axis from the Rapto point. &nbsp;You can display the avoidance geometry for verification.</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">The clearance plane is not inherited from the MCS geometry group.</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">When you specify one of the four points, the point constructor will default to the point you specified, even if it was one of the other three.</p>
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      <div class="title_division">Engage/Retract</div>
      <p class="para_division">The Non Cutting motions can be included in the thread motion through Engage/Retract menu which appears by activating the Engage/Retract button .&nbsp;</p>
      <div class="title_division">Minimum Clearance</div>
      <p class="para_division">Minimum Clearance allows you to define a safety zone around the work piece for non-cutting tool motions. If the engage or retract distance is less than minimum clearance, then engage and retract distance is equal to minimum clearance value.</p>
      <div class="title_division">Rapto Distance</div>
      <p class="para_division">This is similar to a Start Point for each of the specified geometry. In the case of internal thread machining, the tool positions at the center of the hole to be milled at a distance above the specified Rapto distance. In the case of external threads, the tool positions above the first engage point at a Rapto distance.</p>
      <div class="title_division">Start Angle</div>
      <p class="para_division">If the engage angle is zero, the tool will engage with the part at zero degrees as shown below in Figure 1. &nbsp;&nbsp;</p>
      <p align="center"><img align="bottom" src="graphics/thrm_helical_eng.gif"></p>
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               <p class="para_th">Figure 1 Engage and Retract at Zero Degrees on the Circumference</p>
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            <td colspan="1" rowspan="1">
               <p class="para_td">1</p>
            </td>
            <td colspan="1" rowspan="1">
               <p class="para_td">Major Thread Diameter</p>
            </td>
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               <p class="para_td">2</p>
            </td>
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               <p class="para_td">Engage at Zero Degrees</p>
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               <p class="para_td">3</p>
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            <td colspan="1" rowspan="1">
               <p class="para_td">Minor Thread Diameter</p>
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      </table><br><div class="title_division">Overlap Distance</div>
      <p class="para_division">This is the distance along the major diameter after the tool has completed one cutting revolution. The Overlap Distance will assure a full cleanup at the point where the engage move occurs. The overlap distance field is grayed out if the overlap angle toggle is switched ON.</p>
      <div class="title_division">Overlap Angle</div>
      <p class="para_division">This is the angle after the tool has completed one cutting revolution. The Overlap Angle will assure a full cleanup at the point where the engage move occurs.</p>
      <div class="title_division">Engage</div>
      <div class="title_division">Method</div>
      <p class="para_division">The available engage methods are linear, circular, helical.</p>
      <div class="title_division">Linear Engage</div>
      <p class="para_division">Linear engages are straight line moves that bring the cutter into contact with the part. In Linear engages for external threads, the tool engages tangentially to the thread. While machining internal threads, the tool engages linearly along the radial direction for this motion. The required input for the Linear engage is Distance.</p>
      <div class="title_division">Circular Engage</div>
      <p class="para_division">The tool engages circularly for this method. The required inputs for this method are Radius and Distance. The Distance should not be greater than Radius.</p>
      <div class="title_division">Helical Engage</div>
      <p class="para_division">Helical engages are circular moves with a z-axis move along the thread axis. This movement is controlled by the pitch of the thread. This motion brings the cutter in contact with the work piece surface to be finished. These engages are generally used for internal threads. The required inputs for this engage method are Distance and Radius. The Distance should not be greater than Radius.</p>
      <div class="title_division">Distance</div>
      <p class="para_division">This is the distance away from the material to be cut during Engage. The tool will engage to the material to cut in this safe distance. If this is less than the minimum clearance distance, the engage distance will be the clearance distance. This is same with the Retract.</p>
      <div class="title_division">Radius</div>
      <p class="para_division">This is the radius of the circular arc made during circular or helical engage/retract.&nbsp;</p>
      <div class="title_division">Retract</div>
      <div class="title_division">Method</div>
      <p class="para_division">The available Retract methods are linear, circular, helical.</p>
      <div class="title_division">Linear Retract</div>
      <p class="para_division">In Linear Retract method for external threads,&nbsp; the tool retracts tangentially to the thread. In Internal threads, the tool retracts linearly along the radial direction.</p>
      <p class="para_division">The required input for this retract method is Distance.</p>
      <div class="title_division">&nbsp;Circular Retract</div>
      <p class="para_division">The tool retracts circularly for this method. The required inputs for this retract method are Distance and Radius. The Distance should not be greater than Radius.</p>
      <div class="title_division">Helical Retract</div>
      <p class="para_division">Helical Retracts are circular moves with a z-axis move along the thread axis. This movement is controlled by the pitch of the thread. The required inputs for this Retract method are Distance and Radius. The Distance should not be greater than Radius.</p>
      <div class="title_division">Distance</div>
      <p class="para_division">This is the distance away from the material to be cut during Retract. If this is less than the minimum clearance distance, the engage distance will be the clearance distance. This is the same with the Retract.</p>
      <div class="title_division">Radius</div>
      <p class="para_division">This is the radius of the circular arc made during circular or helical engage/retract.</p>
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