Why the 2nd dimension will overconstrain this sketch?

[ecnels]

Hi Folks:

Note the sketch in the enclosed  file.  Constraining either the vertical or horizontal lines between the fillets by adding a dimension to either the horizontal or vertical line does not allow a dimension to be added to the other line, i.e. attempting to dimension the second line will overconstrain the sketch.  Why does the attempt to dimension the second line overconstrain the sketch?

Thanks!

[James.Youmatz]

Hi @ecnels,

I just recreated that sketch from scratch and got the same error! I think it has to do with the preview functionality of showing the colors for a constrained sketch. I do note that I originally created my sketch without that preview function on and it worked fine. As soon as I switched it over to being on, I deleted that dimension and tried to put it back in and got the over constrained warning. I then tested this again by turning it back off and putting the dimension in and it seemed to work. Can you try that out? Go into your preferences and turn off the sketch constraints color preview and then try to add the dimension? Does that seem to fix it?

[martin.zatecka]

Hello,

I guess there is some constraint which defined the horizontal side. As you can see the centers of fillets are black, it means fully constrained.

Please would you share the design with me. I would try to look at it.

regards

[ecnels]

James:  I set the Preview Constraints option to unchecked and the dimension was allowed; however, I then received a Reference Failure Warning.  That warning reappears each time that now-acceptable dimension's editing box is closed.

Thanks guys for the help.  Note the two new attachments.

[fulcrumusa]

I don't think it's entirely clear what is going on. At the very least, there are issues with the preview function which determines whether something is fully constrained. I've had issues with that function too.

Having said that, if the bottom horizontal side is fully constrain as shown in the attached image (it is colored as black), it makes perfect sense that the top horizontal side will also be fully constrained. This is due to the constraint on the size of the vertical sides plus the tangent constraints on the corners. The combination of the tangent constraint on the corner, size constraint on the vertical side, and constraint on the bottom horizontal side fully constrains the top horizontal side.

[James.Youmatz · Accepted solution]

Hi @ecnels,

EDIT: See @Pavel_Holecek's response below. The issue is the point in the circle below. Once deleted, the warning message goes away.

You can get rid of this warning message by redefining your sketch plane for that sketch. To do this, you will need to hover to the yellow sketch icon on your timeline, right-click it and select "Redefine Sketch Plane". Then select the sketch plane it was created on (I believe it was the XZ plane). Then, go into the Modify menu and select Compute All. This will recompute your timeline and the warning will disappear. You can reconfirm this by editing the dimension in your sketch as well. 

Thanks,

[martin.zatecka · Accepted solution]

Hello,

honestly I'm not sure what exactly is wrong, the geometry in sketch is broken. Maybe James will find something.

Anyway I deleted the rectangle geometry and created the new one. "The project source is lost" relates with the point on circle, I deleted the point and it is ok.

I would suggest to use fillet command at all corners in one run, you gain easier control. On the other hand it is better to keep sketches simple and apply fillets on the body.

 

here is the link of design with fixed geometry. http://a360.co/1Ui0o60

regards

[Pavel_Holecek · Accepted solution]

Hello,

there is enough to remove unreferenced geometry to repair your sketch. I marked problematic part in attached image.

Regards

[jiang_peng · Accepted solution]

I tried latest development build. The problem is already fixed. The fix will be included in future updates.

Thanks for reporting this!

[ecnels]

You guys are good - Fast and Thorough;so, WOW,  Thank You!