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      <div class="title_topic3" id="xps10_pagetitle">Cutout tips and techniques</div>
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               <p class="para_td"><a class="links" href="javascript:void(0)" onclick="top.openFile('sheetmetaldes/smfea_cutout.html');return(false);">Cutout Overview</a></p>
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               <p class="para_td"><a class="links" href="javascript:void(0)" onclick="top.openFile('sheetmetaldes/smfea_cutout_dia.html');return(false);">Options</a></p>
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               <p class="para_td"><a class="links" href="javascript:void(0)" onclick="top.openFile('sheetmetaldes/build_multi_parts.html');return(false);">Related Topics</a></p>
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      </table><br><div class="title_division">Punch and through cutouts</div>
      <p class="para_division">If you want to create one Cutout that pierces the target solid just once, use the <b class="uiTerm">Punch</b> cutout type. The <b class="uiTerm">Through</b> cutout type creates multiple cutouts piercing all faces in its path between the placement face and the through face.
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      <div class="title_division">Model state</div>
      <p class="para_division">The <b class="uiTerm">Model State</b> is the formed or unformed condition of the formable features on the target body. For example, if you were to place a cutout on an unformed flange, changes to the placement outline will be ignored when you form the flange. This is because trying to project the changed curves will produce a different cutout on the formed flange than on the unformed flange.
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      <p class="para_division">If you edit the <b class="uiTerm">Cutout</b> feature using the <b class="uiTerm">Edit Parameters</b> dialog box, the system will determine if the model is in the feature creation state. If it isn't, you are warned that the current state will become the new feature creation state. You can disable editing when not in the creation state by choosing the <b class="uiTerm">Enforce Creation State Editing</b> option in the <b class="uiTerm">Preferences</b> dialog box. When this <b class="uiTerm">Preference</b> is enabled, a dialog will be displayed if you try to edit a cutout feature that is not in the creation state and you will not be allowed to edit the cutout.
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      <div class="title_division">Update</div>
      <p class="para_division">Legacy cutout features do not contain the feature creation state information that allows the system to determine when to build them as undistorted or distorted features. When this information is unavailable, the system will build the feature using the existing distortion technique. If you edit the feature, the current <b class="uiTerm">Model State</b> will become the creation state of the feature.
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      <div class="title_division">Tangent edges</div>
      <p class="para_division">If the placement curves used to construct the cutout are tangent to an edge, the cutout may fail while trying to subtract from the target solid. In cases where the placement curves are tangent at the outer edge of the solid body, you can add lines to the outline to avoid the problem. The illustration below shows a cutout being used to trim a L&ndash;shaped solid body. In the example on the left, the curves of the cutout are tangent to the outer edges of the solid. By adding small, straight&ndash;line segments, the tangency problem can be avoided. The example at the right shows these lines.</p>
      <p align="center"><img align="bottom" src="graphics/tangent_image.gif"></p>
      <div class="title_division">General tips</div>
      <p class="para_division">A <b class="uiTerm">Sketch</b> may be used to define the outline of a cutout, but the placement face of the sketch cannot be the bend face of the flange, inset flange, or bend when the features are unformed. &nbsp;When the feature forms, this bend face becomes a cylindrical face. &nbsp;The <b class="uiTerm">Web Face</b> may be used, because this face is always the planar face.
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      <p class="para_division">If the <b class="uiTerm">Sketch</b> is not constrained positional, the <b class="uiTerm">Sketch</b> might fail when the <b class="uiTerm">Self&ndash;Forming Feature</b> is formed/unformed. &nbsp;You should not use a bend edge to create a positional constraint as this constraint might fail when the Self&ndash;Forming feature is formed/unformed, because this edge changes from a cylindrical to linear edge.
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      <p class="para_division">If you want to create a cutout, so that part or all of the cutout resides on the bend face of a flange, inset flange, or bend, it should be unformed. &nbsp;This will allow the edges of the cutout to create on the flat pattern as lines or arcs, where appropriate.</p>
      <p class="para_division">If you use a <b class="uiTerm">Sketch</b> to define the cutout on a general flange or bridge, a datum plane will be required for the Placement face, because any face on a general flange and a bridge is a b&ndash;surface.
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      <p class="para_division">If you edit a <b class="uiTerm">Sketch</b> used to create a cutout, the cutout will not update until in its creation state. What this means is if you edit a <b class="uiTerm">Sketch</b> with the <b class="uiTerm">Self&ndash;Forming Feature</b> formed, assuming that you created the cutout with the <b class="uiTerm">Self&ndash;Forming Feature</b> unformed, the cutout will not change until the <b class="uiTerm">Self&ndash;Forming Feature</b> is unformed. We recommend that you make all of your sketch edits then unform the entire model. This would allow you to only go through one update cycle of the model.
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      <p class="para_division">The cutout wants to cut a body.&nbsp;When the outline curves that will be used by the cutout are sitting on two distinct areas of the body you might have to create two cutouts to get the desired results. You can see an example of this below.</p>
      <p align="center"><img align="bottom" src="graphics/cutout1.gif"></p>
      <p class="para_division">Divide the circle into two parts and create two cutouts, then the area inside the circle will remove.</p>
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