Constraining Sketches: Must a sketch reference the Origin to become fully constrained?

[Anonymous]

Must a sketch reference the Origin to become fully constrained? I know doing so has allowed me to fully constrain simple practice sketches at times however I have not determined whether doing so is a requirement. Does anyone know whether referencing a sketch to the workspace Origin (or Origin of the plane used, if different from the workspace Origin) is a requirement to making a sketch fully constrained?

[yqliu]

No, it's not required, although in most cases it's easier to make the sketch fully constrained if reference to the origin in some way.

Example:

[jhackney1972 · Accepted solution]

A sketch must reference a static entity to the world.  If that is the origin of the model or the edge of another body.  It must have some kind of fixed reference.  A new workplane will have its own origin so you can use it to constrain your sketch to it.  It is not a requirement of Fusion 360 to have a sketch constrained but you want to do it for a few reasons.  Your model will be more stable and as you build it, strange changes will not happen.  Fusion 360 will be fast if your sketches do not have to be solved every time if updates.  Others working with your design are less likely to make a mistake if your sketch is stable.  You WANT TO CONSTRAIN YOUR SKETCHES.

[Anonymous]

@yqliu  I cannot duplicate your square. I cannot fully constrain it. What is the dot in the upper left corner of your square?

[Anonymous]

John, I was able to fully constrain the square without directly referencing the Origin by referencing an entity that references the Origin. I think this was the type of thing you are suggesting is required (as per your diagram too); a direct or indirect reference to a workspace Origin or other plane Origin.

[davebYYPCU · Accepted solution]

Fix a corner point.  Hardly a parametric result.

[Anonymous]

Got it. Thanks @davebYYPCU .