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      <title>Stepover or Percentage</title>
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      <div class="title_topic3" id="xps10_pagetitle">Stepover or Percentage</div>
      <hr noshade="true">
      <p class="para_topic">This option allows you to specify the size of the stepover by entering either a stepover distance or percentage value (depending on whether the auto method is set to Stepover or Percentage).</p>
      <p class="para_topic">Stepover allows you to enter an absolute stepover distance. Percentage allows you to enter a value relative to the tool width or the maximum groove depth. When plunge cutting, the stepover is measured along the tool holder width and the percentage value times the tool width determines the stepover. When cutting by level, the stepover is measured along the tool holder length and the percentage value times the maximum groove depth determines the stepover. The percentage value may be input as a decimal fraction or a whole number. That is, 50% may be input as .5 or 50.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg12.gif"></p>
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      <div class="title_figure">By Level and Plunge Cut Methods</div>
      <div class="title_division"> Clear Excess</div>
      <p class="para_division">Clear Excess allows you to remove the excess stock remaining in groove corners between passes when rough cutting. This option is available only when Cut Type is set to Rough Only or Rough and Finish. Clear Excess toggles between YES and NO.</p>
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            <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
            <td valign="bottom" align="left" width="100%">
               <div class="para_note">
                  <p class="para_note_body"> NOTE: Custom Feed Rates only apply to Clear Excess movements when roughing and for the finishing pass.</p>
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            </td>
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      <p class="para_division">For grooves with angled walls, Clear Excess should be set. This will prevent possible undercuts.</p>
      <p class="para_division">When cutting by levels, Clear Excess will change the shape of the tool path to allow the clearing of the material along the walls as illustrated below.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg13.gif"></p>
      </div>
      <div class="title_figure">Plunge - Left to Right Tool Paths</div>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg14.gif"></p>
      </div>
      <div class="title_figure">Left to Right Roughing Tool Paths</div>
      <table border="0">
         <tr>
            <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
            <td valign="bottom" align="left" width="100%">
               <div class="para_note">
                  <p class="para_note_body"> NOTE: Right to Left roughing tool paths will be similar to Left to Right roughing tool paths.</p>
               </div>
            </td>
         </tr>
      </table>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg15.gif"></p>
      </div>
      <div class="title_figure">Zig-Zag Roughing Tool Paths</div>
      <div class="title_division"> Relief Plunge</div>
      <p class="para_division">Relief Plunge allows you to begin cutting each level with an additional plunge a slight distance from the Part boundary. This causes additional material to be removed adjacent to the boundary and provides a space that can prevent the trailing corner of the tool from gouging the part when performing sideways cuts.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lgroov_figlg16.gif"></p>
      </div>
      <div class="title_figure">Gouging Due to Tool Deflection</div>
      <p class="para_division">The first plunge (relief plunge) removes material adjacent to the boundary. The tool then retracts, traverses in the cutting direction a distance of half the tool insert width, and applies the second plunge to remove additional material as illustrated below. The tool then begins the sideways cut at a safe distance from the boundary.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lgroov_figlg17.gif"></p>
      </div>
      <div class="title_figure">Additional Space Provided for Tool Deflection</div>
      <p class="para_division">If the groove is too narrow to allow an offset of half the tool insert width, the second plunge is positioned half way between the sides of the groove or half way between the sides of the region in a multi-region groove.</p>
      <p class="para_division">Relief Plunges can be applied only when using Level cut methods (Zig-Zag, Left to Right, or Right to Left) and when the Cut Type is set to Rough Only or Rough and Finish. The Relief Plunge option is not available and will display Not Used if a Plunge cut method is specified (Alternate, Left to Right, Right to Left), or if the Cut Type is set to Finish Only.</p>
      <p class="para_division">The following figure illustrates how Relief Plunges are applied to each level of a tool path that uses a Rough Only cut type and a Level Left to Right cut method.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg18.gif"></p>
      </div>
      <div class="title_figure">Relief Plunges for Level Left to Right</div>
      <p class="para_division">In the above figure, the system applies a Relief Plunge (1) to the beginning of the first level. The tool then retracts (2), traverses to the right, and applies the second plunge (3). The tool then applies the Left to Right cut (4) for the first level. The tool retracts, traverses to the left (5), and the sequence repeats for the next level.</p>
      <p class="para_division">For Level Zig-Zag cut methods, the sequence of moves is similar to that of Level Left to Right except that the the Relief Plunges (1 and 6) occur at opposite ends of each level as illustrated below.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg19.gif"></p>
      </div>
      <div class="title_figure">Relief Plunges for Level Zig-Zag</div>
      <p class="para_division">When Clear Excess is set to Yes and used with a Level Zig-Zag cut method, all contouring on the current level is completed before plunging to the next level. Because the downward contour direction removes material along the boundary, only a single plunge is applied at each level. In the following figure, Clear Excess is set to Yes and Contour Direction is set to Cut Down and Up</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg20.gif"></p>
      </div>
      <div class="title_figure">Relief Plunges for Level Zig-Zag and Clear Excess</div>
      <p class="para_division">In the above figure, the system applies a Relief Plunge (1) to the beginning of the first level. The tool then retracts (2), traverses to the left (3), and applies a downward contour cut (4) to the first level. The tool then cuts to the right (5), retracts (6), and traverses (7) to begin the second downward contour cut to the first level (8). At this point, the first level is complete. The tool now retracts (9), traverses to the left (10), and applies a Relief Plunge (11) to the beginning of the second level. The tool then retracts (12) to apply the downward contour cut (13) to the second level.</p>
      <div class="title_division"> Chip Control</div>
      <p class="para_division">Chip Control allows you to specify a method for clearing or breaking chips as you are grooving. Chip Control is only available for plunge cutting. It is not applied when level cut methods (left-to-right, right-to-left, or zig-zag) are used. The system displays the following options:</p>
      <p class="para_division">None indicates that no chip control should be applied.</p>
      <p class="para_division">Constant Break allows you to define equal depth plunge moves. The tool does not retract which breaks the chip. A DELAY command is included in the tool path after each forward move.</p>
      <p class="para_division">Variable Break allows you to define variable depth plunge moves. The tool does not retract which breaks the chip. A DELAY command is included in the tool path after each forward move.</p>
      <p class="para_division">Constant Clear allows you to define equal depth plunge moves. The difference between this option and Constant Break is that the tool fully retracts out of the groove after every incremental step. This helps clear the chips out of the groove.</p>
      <p class="para_division">Variable Clear allows you to define variable depth plunge moves. The difference between this option and Varaible Break is that the tool fully retracts out of the groove after every incremental step. This helps clear the chips out of the groove.</p>
      <p class="para_division">If the total distance specified by the # Moves and Increments (in the Variable method) exceeds the groove depth, then the system ignores the excess amount.</p>
      <p class="para_division">First Cut Only allows you to indicate whether chip control will be applied to the first plunge only or to every incremental step as the tool advances into the groove. This option is not available if Chip Control is None. You may set this option to the following:</p>
      <p class="para_division">YES-Chip control will be applied to the first plunge only.</p>
      <p class="para_division">NO-Chip control will be applied to every plunge. NO is the default.</p>
      <div class="title_division"> Contour Direction</div>
      <p class="para_division">Contour Direction determines the direction in which the tool moves along the Part when finishing or when roughing and clearing excess material. It allows you to cut downward only or downward and upward on contouring moves between cut levels. Contour Direction is not available (displays as &quot;Not Used&quot;) if Cut Type is set to Rough Only and Clear Excess is set to No.</p>
      <p class="para_division">Contour Direction toggles between Cut Down Only and Cut Down and Up. The following figure illustrates the difference in the sequence of tool movements between a Cut Down Only and Cut Down and Up Contour Direction when used with a Finish Only type of cut.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg21.gif"></p>
      </div>
      <div class="title_figure">Contour Directions Used with Finish Only Cut Type</div>
      <p class="para_division">Avoidance moves differ depending on whether a one-way or two-way Cut Method is used with the specified Contour Direction. The following figure, for example, illustrates a Cut Down and Up Contour Direction used with a Level Left to Right Cut Method (one-way cut) and a Rough and Finish Cut Type.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg22.gif"></p>
      </div>
      <div class="title_figure">One way (Level Left to Right) Cut Method</div>
      <p class="para_division">In the above figure, the tool cuts sideways (2) until it contacts the boundary. It then contours upward (3) and performs an avoidance move (4, 5) back to the starting (left) side.</p>
      <p class="para_division">In contrast, the following figure illustrates a Cut Down and Up Contour Direction used with a Level Zig-Zag Cut Method (two-way cut) and a Rough and Finish Cut Type.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg23.gif"></p>
      </div>
      <div class="title_figure">Two way (Level Zig-Zag) Cut Method</div>
      <p class="para_division">In the above figure, the tool cuts sideways (2) until it contacts the boundary. It then contours upward (3) and performs an avoidance move (4, 5) to start the next cut in the opposite direction (7, 8, 9).</p>
      <div class="title_division"> Finish Sequence</div>
      <p class="para_division">This option is only displayed when the Cut Type is set to either Finish Only or Rough And Finish.</p>
      <p class="para_division">Finish Sequence toggles between the following settings:</p>
      <ul>
         <li>
            <p class="para_item">Boundary Direction allows your finish pass to follow the direction of the boundary.</p>
         </li>
         <li>
            <p class="para_item">Left to Right allows your finish pass to start left and proceed right.</p>
         </li>
         <li>
            <p class="para_item">Right To Left allows your finish pass to start right and proceed left.</p>
         </li>
      </ul>
      <p class="para_division">The following settings are used for face grooving, but they work similarly to the settings described above:</p>
      <ul>
         <li>
            <p class="para_item">Boundary Direction</p>
         </li>
         <li>
            <p class="para_item">Upper To Lower</p>
         </li>
         <li>
            <p class="para_item">Lower To Upper</p>
         </li>
      </ul>
      <div class="title_division"> Corner Control</div>
      <p class="para_division">Corner Control allows you control whether the tool cuts a round, chamfer, or sharp edge on every convex corner of your groove. This option allows you to cut these features without defining them in your boundary. The corner cuts are made during the profile (finish) pass of the operation and apply only to corners within the groove as illustrated below.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_figlg24.gif"></p>
      </div>
      <div class="title_figure">Round Corners</div>
      <p class="para_division">The following options are available:</p>
      <p class="para_division">These options work similarly to options in Lathe Rough. Refer to Corner Control under Lathe Rough for details.</p>
      <p class="para_division">Roll Sharp allows you to have the tool path make a circular path around corner while keeping the tool against the boundary. This option does not cut the corner.</p>
      <p class="para_division">Clear allows you to just have the tool path follow the boundary. This option does not cut the corner.</p>
      <p class="para_division">Round allows you to round off the corner. Enter the radius that you want the corner to have.</p>
      <p class="para_division">Break allows you to cut a chamfer in the corner. Enter the break distance into the system. The break distance is measured along the turning axis.</p>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/lathe/lgroov_groAt23.gif"></p>
      </div>
      <div class="title_figure">Length of Break</div>
      <p class="para_division">It is generally not necessary for the boundary to include the chamfers and rounds. Corner Control can cut these features for you. Since using the Round or Break options may violate the boundary, choose Clear when you have already included the chamfer or rounds in your boundary.</p>
      <div class="title_division"> Tolerances</div>
      <p class="para_division">This option allows you to specify Intol and Outtol values that define an allowable range the tool may use to deviate from the Boundary.</p>
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