Replaced BaseGeometry 'Update' with 'Clear', since update didn't actually do anything and 3 buttons is consistent with the BaseLocation dialog.

src/Mod/Path/Gui/Resources/panels/PageBaseGeometryEdit.ui

@@ -17,12 +17,12 @@
    <item>
     <layout class="QGridLayout" name="gridLayout">
      <item row="1" column="2">
-      <widget class="QPushButton" name="updateBase">
+      <widget class="QPushButton" name="clearBase">
        <property name="toolTip">
-        <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Upates the Model.&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+        <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Clears list of base geometries.&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
        </property>
        <property name="text">
-        <string>Update</string>
+        <string>Clear</string>
        </property>
       </widget>
      </item>
@@ -71,7 +71,7 @@
   <tabstop>baseList</tabstop>
   <tabstop>addBase</tabstop>
   <tabstop>deleteBase</tabstop>
-  <tabstop>updateBase</tabstop>
+  <tabstop>clearBase</tabstop>
  </tabstops>
  <resources/>
  <connections/>

src/Mod/Path/PathScripts/PathOpGui.py

@@ -308,11 +308,14 @@ class TaskPanelBaseGeometryPage(TaskPanelPage):
         #self.obj.Proxy.execute(self.obj)
         #FreeCAD.ActiveDocument.recompute()
 
+    def clearBase(self):
+        self.obj.Base = []
+
     def registerSignalHandlers(self, obj):
         self.form.baseList.itemSelectionChanged.connect(self.itemActivated)
         self.form.addBase.clicked.connect(self.addBase)
         self.form.deleteBase.clicked.connect(self.deleteBase)
-        self.form.updateBase.clicked.connect(self.updateBase)
+        self.form.clearBase.clicked.connect(self.clearBase)
 
     def pageUpdateData(self, obj, prop):
         if prop in ['Base']: