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      <title>Prevent Undercutting</title>
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      <div class="title_topic3" id="xps10_pagetitle">Prevent Undercutting</div>
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      <p class="para_topic"><b class="uiTerm">Prevent Undercutting</b> prevents the shank from rubbing against the part geometry by allowing the system to consider undercut geometry when generating the tool path. 
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      <p class="para_topic">When <b class="uiTerm">Prevent Undercutting</b> is toggled ON for cavity milling, the system applies the full Horizontal Clearance (specified under Engage/Retract Method) to the shank of the tool (unless the Horizontal Clearance is greater than the tool radius in which case the tool radius is applied). When the shank is above the undercut a distance equal to the tool radius, the tool begins to progressively move away from the undercut as it cuts deeper through the cut levels. The Horizontal Clearance is fully applied once the shank reaches the undercut.
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      <div class="title_figure">Horizontal Clearance Applied with Undercut Handling</div>
      <p class="para_topic">When <b class="uiTerm">Prevent Undercutting</b> is toggled ON for face milling, the minimum clearance for avoidance is applied to the tool shank. Horizontal and Vertical clearance are used to determine how far engage/retracts should extend beyond the cutting region.
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                  <p class="para_note_body"> NOTE: Processing time is slowed down when <b class="uiTerm">Prevent Undercutting</b> is toggled on. If no deliberate undercut areas exist, toggle it Off to speed up processing time.
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      <p class="para_topic">When <b class="uiTerm">Prevent Undercutting</b> is toggled OFF, the system will not account for undercut geometry. This results in looser tolerances in processing vertical walls. If you are importing geometry to be processed in Manufacturing, keeping this option toggled off will help compensate for problems in translation or models that aren't very clean.
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                  <p class="para_note_body">The clearance distance is in addition to any part/check stock values. For example: If the part stock is 1 mm, check stock is 2 mm, and the minimum clearance is 0.5 mm, the holder and shank would clear the actual part geometry by at least 1.5 mm and the check geometry by 2.5 mm.</p>
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                  <p class="para_note_body">The <b class="uiTerm">Prevent Undercutting</b> option also affects the behavior of the tool at floor edges. See <a class="links" href="javascript:void(0)" onclick="top.openFile('mfgmilling/fm_behav_floor_edge.html');return(false);">Behavior at Floor Edges</a> for more information.
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      <div class="title_division">Using Undercut Handling</div>
      <p class="para_division"><img align="bottom" src="graphics/use_tool_holder-undercut.gif" border="0"></p>
      <p class="para_division">To mill a face below an overhang:</p>
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            <p class="para_item"> Define either a T-Cutter, or a mill with a holder/shank smaller than the tool diameter, that will reach the undercut areas.</p>
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            <p class="para_item">Turn off <b class="uiTerm">Prevent Undercutting</b> on the <b class="uiTerm">Cut Parameters</b> dialog, <b class="uiTerm">Strategy</b> page.
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            <p class="para_item">Turn on <b class="uiTerm">Use Tool Holder</b> on the <b class="uiTerm">Cut Parameters</b> dialog, <b class="uiTerm">Containment</b> page.
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            <p class="para_item">Define a minimum clearance (A) to apply to the non-cutting portions of the tool/holder on the <b class="uiTerm">Engage/Retract Method</b> dialog.
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