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      <title>Maximum Tool Axis Change</title>
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      <div class="title_topic3" id="xps10_pagetitle">Maximum Tool Axis Change</div>
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      <p class="para_topic">Maximum Tool Axis Change enables you to control drastic changes in the tool axis on Part Surfaces caused by sudden changes in surface normals over small distances. It allows you to specify a value in degrees that limits the allowable angular change of the tool axis per cut step or per minute. Maximum Tool Axis Change is available only for Variable Contour operations.</p><a name="com_cut_cut_param-max_tool_axis_chg-step"></a><div class="title_division">Per Step</div>
      <p class="para_division">Per Step enables you to specify a value in that limits the allowable angular change of the tool axis in degrees per cut step. If a step requires a tool axis change that exceeds the specified limit, then additional smaller steps are inserted so that the specified Maximum Tool Axis Change value per step is not exceeded.</p>
      <p class="para_division">The following figure illustrates how additional steps are inserted when a very small Per Step value is specified.</p>
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         <p align="center"><img align="bottom" src="graphics/maxtoolaxchng.gif"></p>
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      <div class="title_figure">Maximum Tool Axis Change</div>
      <p class="para_division">A small Per Step value creates a smoother tool axis movement which can yield a smoother finished surface. Specifying too small of a Per Step value, however, may cause the tool to dwell excessively in one area.</p><a name="com_cut_cut_param-max_tool_axis_chg-min"></a><div class="title_division">Per Minute</div>
      <p class="para_division">Per Minute enables you to specify a value that limits the allowable angular velocity of the tool axis in degrees per minute. It can prevent the rotary axis from oscillating excessively due to small wave-like shapes in the surface as well as prevent the tool from leaving dwell marks in sharp corners. Specifying a relatively small value makes the tool axis less sensitive to sudden changes in the surface normals and yields a toolpath with less tool axis change as illustrated below.</p>
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         <p align="center"><img align="bottom" src="graphics/smvalu_tacm.gif"></p>
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      <div class="title_figure">Smaller Value Limits the Tool Axis Change Per Minute</div>
      <p class="para_division">This option should be used when the tool axis depends on surface normals (ex. Normal to Part, Relative to Drive, Dual 4-Axis on Drive) and when finishing surfaces with sharp corners or containing microscopic wave-like shapes which can be amplified greatly by the tool. Per Minute is not available when Interpolate has been specified as the tool axis.</p>
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