How do I add lines to a sketch?

[smurfix]

Hi,
Problem: I have created a sketch in Parts Designer, added a pad, added another sketch for a pocket on top of that, and so on. Now I need to modify the initial sketch (to add two corners, not just change dimensions). However, even simply removing and re-adding a line in the initial sketch messes up my design -- the additional sketches seem to be attached to the wrong surface, "Result has multiple solids" messages, the works.

Of note: the second sketch contains an external reference of three points from the first. I suspect that the references get messed up when the first sketch is changed and I should file a bug report ..?

FreeCARD 0.18.4, Debian. File attached.

[chrisb]

Please read about Topological naming problem in the wiki or search the forum for that term. You cannot completely avoid it but you can reduce the effects. Have a look at this page, especially the paragraph about creating stable models.

[vocx]

...
Of note: the second sketch contains an external reference of three points from the first. I suspect that the references get messed up when the first sketch is changed and I should file a bug report ..?

Yes, that is what happens due to the topological naming problem. You don't need to report it as a bug because we are aware of it. Solutions are being investigated and will probably be deployed in the next development version, so maybe 0.20.

At the moment the solution is to follow best practices in modelling and avoid supporting the sketches directly on faces. Use auxiliary geometry like PartDesign Planes to support your sketches.