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      <title>Stepover</title>
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      <div class="title_topic5" id="xps10_pagetitle">Stepover</div>
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      <p class="para_topic">Stepover specifies the distances between successive cut passes, as shown below. &nbsp;The 1 indicates the scallop height, and the 2 indicates the stepover.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/stepover_scallop.gif"></p>
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      <div class="title_figure"> Stepover</div>
      <p class="para_topic">The Stepover options that are available are determined by the specified cut pattern (Follow Periphery, Profile, Parallel, Riadial, and Concentric) and the associated cut patterns for Parallel, Radial, and Concentric (Zig, Zig-Zag, Zig with Lifts, etc.). The numeric value or values required to define the stepover will vary depending on the stepover option selected. Constant, for example, requires that you enter a distance value in the subsequent line, while Variable displays an additional dialog box and requires several values. &nbsp;The following stepover options are available:</p>
      <div class="title_division">Constant</div>
      <p class="para_division">Constant allows you to specify a fixed stepover distance between successive cut passes. Stepover distance is measured between the cut passes of the drive path. When used with the Radial Lines cut type, the Constant distance is measured along the arc length at the boundary point farthest away from the center. This option is similar to the Constant option in Planar Milling.</p>
      <div class="title_division">Scallop</div>
      <p class="para_division">Scallop allows the system to determine the stepover distance based on the scallop height you enter. The stepover calculation is computed on a plane normal to the tool axis. The system limits the size of the stepover to roughly less than two-thirds of the tool diameter regardless of what you specify as the scallop size. </p>
      <div class="title_division">Tool Diameter</div>
      <p class="para_division">Tool Diameter allows you to define the stepover in terms of a percentage of the effective tool diameter. The effective tool diameter is the diameter of the cutter that actually touches the floor of your pocket. For ball end mills, the system uses the full tool diameter as the effective tool diameter. This option is similar to the Tool Diameter option in Planar Milling.</p>
      <div class="title_division">Variable</div>
      <p class="para_division">Variable allows you to vary the stepover distance within a specified minimum and maximum value. The required input values differ depending on the selected Cut type. This option is similar to the Variable option in Planar Milling.</p>
      <div class="title_division">Apply Stepover</div>
      <p class="para_division">In the Area Milling Drive Method dialog, you can apply stepover by toggling either On Plane or On Part. &nbsp;</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/onplane.gif"></p>
         <p align="center"><img align="bottom" src="graphics/onpart.gif"></p>
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      <div class="title_figure">On Plane &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On Part &nbsp;&nbsp;&nbsp;&nbsp;</div>
      <p class="para_division">On Plane</p>
      <p class="para_division">If On Plane is toggled, then, when the system generates the tool path for the operation, the stepover is measured on a plane normal to the tool axis. &nbsp;If this tool path is applied to a part which has steep walls, like the one shown below, the actual stepover distance on the part will not be even. &nbsp;Therefore, On Plane works best for non-steep areas.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/onplane_stepover.gif"></p>
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      <div class="title_figure">On Plane Stepover Distance</div>
      <p class="para_division">On Part</p>
      <p class="para_division">On Part is available with the Follow Periphery and Parallel cut pattern that uses the Zig Zag cut types. &nbsp;&nbsp;If On Part is toggled, then, when the system generates the tool path for the operation, the stepover is measured along the part. &nbsp;Because On Part measures the stepover along the part, it works well for parts with steep walls. &nbsp;Thus, you can maintain tighter stepover on steeper portions of the part geometry so that you attain additional control over the scallops. &nbsp;Notice that in the figure below, the stepover distance is even. </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">Calculating the stepover for On Part requires more time than for On Plane. </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">You cannot use Corner Control with the On Part method.</p>
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      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/onpart_stepov.gif"></p>
      </div>
      <div class="title_figure">On Part Stepover Distance</div>
      <div class="title_division">Additional Passes</div>
      <p class="para_division">Additional Passes enables you to specify an additional number of passes that allow the tool to step outward in successive concentric cuts for Profile cutting patterns. Refer to the discussion of Additional Passes in the Boundary Drive Method for additional details.</p>
      <div class="title_division">Using 3D Stepover for Zig Zag in Area Milling Operations</div>
      <p class="para_division">You can find this functionality in the Drive Parameters dialog for the Area Milling operations. &nbsp;</p>
      <ol type="1" start="1">
         <li>
            <p class="para_item">You must first choose the pattern to be Parallel in the Area Milling Drive Method dialog. </p>
         </li>
         <li>
            <p class="para_item">Then you can click on the check box for the On Plane option or the check box for the On Part option.</p>
         </li>
      </ol>
      <p class="para_division">The graphic below illustrates a Zig Zag cut type for the On Plane option. &nbsp;Because of the steep slopes, the On Plane option results in large stepovers. </p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/onplane_zz.gif"></p>
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      <div class="title_figure">Zig Zag cut type for the On Plane option</div>
      <p class="para_division">The On Part option, in the graphic below, works much better with this part, because the stepovers remain constant in the steep area.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/onpart_zz.gif"></p>
      </div>
      <div class="title_figure">Zig Zag cut type for On Part option</div>
      <p class="para_division">The stepover distance specified is the maximum allowed across the part. The stepover distance can vary (to a value less than the specified stepover distance) based on the curvature of the part.</p>
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