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      <title>Tolerant Machining</title>
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      <div class="title_topic3" id="xps10_pagetitle">Tolerant Machining </div>
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      <p class="para_topic">Cavity Milling, Zlevel Milling</p>
      <p class="para_topic">Tolerant Machining (for Cavity Mill) ON is the preferred method for most milling operations. It is a reliable algorithm to find the correct machinable regions without gouging the part. The Material Side is based on the Tool Axis only. The Tool Position attribute of the faces is treated as Tanto regardless of the user input.</p>
      <p class="para_topic">Since this method does not use the Material Side attribute of the faces, the tool will be positioned to both sides of curves when curves are selected and both sides of vertical walls when the top face is not selected.</p>
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                  <p class="para_note_body"> NOTE: When retrieving pre-V10.6 operations, Tolerant Machining defaults to the OFF position for upward compatibility only. For reliable results, you should turn it ON.</p>
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      <p class="para_topic">When using Tolerant Machining, the processor digitizes the model on a rectangular grid. The size of the grid is a function of the cutting tolerance and the tool size. In common parts, the grid size's range is between 1-2 millimeters. When specifying a Blank distance that is an offset from the Part, the tolerance used to trace the Blank is much looser than the tolerance used to trace the Part. This is done because the dimensions of the Blank geometry do not have to be as accurate as those of the Part geometry. When you specify Blank geometry that is very close to the size of the Part geometry (within the range of the grid size), the Blank traces and Part Traces overlap each other and result in undesirable cut regions. In this case, it is a better practice to cut a Profile path along the Part without specifying the Blank. The result will be a pass along the Part geometry.</p>
      <div class="title_division">Backdraft Conditions</div>
      <p class="para_division">In Cavity Milling, for the tolerant machining method, the system does not try to handle backdraft conditions. Thus when back draft situations occur on the part, the tool acts as if there is a vertical wall parallel to the tool axis. &nbsp;The operation with a tapered bore has the blank that is higher than the part along the same taper. &nbsp;This extends the wall of the blank beyond the part for all the cut levels. So, to the system, it appears as if there is material between the part and the blank that needs to be removed. &nbsp;This results in the unexpected tool path for that operation. </p>
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