Underconstrained

[Cad4fish]

I'm going through the videos again trying to really understand the steps and making a guide sheet to follow in the shop.  I had gone back to where "Same plane faces," "loops," and "sides" are mentioned in the Tool Path video.  I created the sketch shown here to play with as I study those options.  It is simply a rectangle with two fillets and a circle added.  I missed a step in moving to "Manufacture" and thought I had a problem with the sketch.  The sketch does not have the "Lock" icon in the tree so I ran "Sketch.ShowUnderconstrained".  I got this message, "Under constrained points: 9, under constrained curves: 7."  It sure looks constrained to me and after fixing the missed step I was able to complete the manufacture steps.  Any thoughts on where this is not fully constrained?

[jhackney1972 · Accepted solution]

You have no sketch constraint to the Origin.  It is not related to the world.  Drag it around to see the problem.

[jeff_strater · Accepted solution]

I don't see any dimension or constraint to any grounded geometry, such as the sketch origin, or a projected edge.  That is likely the missing constraint.  But, the easiest way to tell is to just try dragging one of the sketch geometries.  It will quickly reveal where the degrees of freedom are.  If you hit ESC before you let up on the mouse, it will abort the drag.  If you forget, undo will undo the drag.  If you share the design, we can show you on your own design.

Also, I noticed that center circle looks like it does not have a diameter dimension.  You'll need that, too.

[Cad4fish]

When I drag any part of the sketch it all moves together.  I did add a dim to the circle.  I don't know what you mean by "grounded geometry," "sketch origin," or "projected edge."

[jeff_strater · Accepted solution]

exactly.  The fact that you can drag the whole thing means that it is internally constrained, but not constrained to anything that will fix it in sketch space.  Usually you use the sketch origin for that:

[jhackney1972 · Accepted solution]

Here is an animated GIF showing the adding of a sketch constraint between the corner of a sketch rectangle to the Origin of the model.  Notice how is constrains two sides immediately.  This is what we mean by constraining your sketch to the Origin.