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If you want to reattach a sketch to a new parent but the icon is grayed out,
what do you need to do to fix it?
Solution
You would first need to reorder the new parent solid to be before the sketch -> Preferences Modeling
-> Edit -> Edit Sketch Action -> Task Environment -> Ok -> Double click to edit the sketch -> Select Reattach on the on sketch toolbar :
--> Set Sketch Type to "On Plane" and Plane Method to New Plane
Now you Shift ->Select the existing face -> Then select the new face from the new solid -> OK
Notes and References
Hardware/Software Configuration
Platform: all
OS: n/a
OS Version: n/a
Product: NX
Application: DESIGN
Version: V12.0.2
Function: SKETCHER
Ref: 001-7929268