Hi Doug...
One alternate method that doesn't require adding an additional axis feature- you can add an AXIS POINT to your slot sketch. This will automatically create an axis within the slot feature. This will show as a set of cross hair sin your drawing.
Depending upon the version of Pro/ENGINEER or Creo you're using, the method for adding this axis point is different. For Wildfire 4 and lower (WF3, WF2), select Axis Point from the top Sketch menu. In Wildfire 5 or later (Creo 1.0+), you add a Geometry Point from the sketcher "point" flyout menu (usually along the right hand side).
Either way, you drop this "point" at the location you want the axis to appear. If you want the axis to appear at the center of the radius of an arc, you can drop the point at the arc centerpoint. When you complete the feature, the axis will appear in your solid model.
One final way to create the axes you need is to set show_axes_for_extr_arcs to yes (in your config.pro file). I personally don't prefer this because if this option is set, you'll start seeing axes anywhere you're extruded an arc rather than just adding them to specific places as necessary. However, some people prefer the convenience of setting an option and having the axes appear automatically.
I hope that gives you some additional options!
Thanks!
-Brian
