Sketcher Formula Expression / Length or Distance Constraint To be shown as Dimensioning

[paullee]

Hi, I find I use a lot of length / distance constraints in a sketch.

These constraints would not show themselves exiting the sketch edit mode. Would there any method to show them so I do not need to add extra dimensioning lines (haven't learnt that yet in fact)?

I also learn from this thread ( Sketcher:How can I constrain a line's length by another externalEdge's length? / https://forum.freecadweb.org/viewtopic.php?t=16178) which is terrific. But I can only identify which figure in the sketches are formula in fact until I click every each of them and the fx button to clarify. Can a mark or otherwise be added to identify any of those figure is in fact a result of a formula?

Thanks!

[DeepSOIC]

Hi!

These constraints would not show themselves exiting the sketch edit mode. Would there any method to show them so I do not need to add extra dimensioning lines (haven't learnt that yet in fact)?

No, that's not possible.

I recall something like that being discussed for drawing/techdraw. But I don't know if it ended with some functionality.

[paullee]

No, that's not possible.

I recall something like that being discussed for drawing/techdraw. But I don't know if it ended with some functionality.

Hi, I think I would try in drawing / techdraw then


Incidentally, about the externalEdge's length, I find I can create a Length Constraint in the original object (must need to give it a optional name?), then I can reference that directly in another object (i.e. w/o creating an additional 'intermediate' sketch... then link external geometry, constraint..etc).

Hope it help someone.

[paullee]

Hi,

I note there is some difference with my model - I create an underlying Sketch (Sketch002 in the file) then extrude to a box, so that a constraint could be added in the first place.

For an object w/o a sketch, DeepSOIC's workflow should be required.


p.s.
I alway find extrude created 2 objects - why is it?

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[chrisb]

I alway find extrude created 2 objects - why is it?

When I extrude Sketch002 I get one Extrude object - as expected. Which FreeCAD version did you use?

[paullee]

I alway find extrude created 2 objects - why is it?

When I extrude Sketch002 I get one Extrude object - as expected. Which FreeCAD version did you use?

Hmm... thanks for the hint.

I tested a few more times and I think I get what have I gotten wrong:-

- I click Apply in the dialog box, then click OK - 2 Extrusion resulted
- Click OK only - 1 Extrusion


So, what is the purpose of the Apply Button ???

[bejant]

Hi, I find I use a lot of length / distance constraints in a sketch.

These constraints would not show themselves exiting the sketch edit mode. Would there any method to show them so I do not need to add extra dimensioning lines (haven't learnt that yet in fact)?

To me it also seems to cause the user extra work to first apply length constraints in a sketch and later have to add dimensions to a drawing page when those dimensions are based on the same length constraints the user previously created. I'd like to see a way to somehow tag a length constraint when it is created in a Sketch so that it appears as a dimension on a drawing page and then all the user has to do is drag the dimension to the desired location on the drawing page. As an example, the distance constraints in the following Sketch:

20170315b.png (30.52 KiB) Viewed 4261 times

OS: Ubuntu 16.04.2 LTS
Word size of OS: 32-bit
Word size of FreeCAD: 32-bit
Version: 0.17.10476 (Git)
Build type: None
Branch: master
Hash: b6150097e9cf4d7b0f5ad71f2f8750f2e7aac0d9
Python version: 2.7.12
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.1.0

[chrisb]

I see good reasons for the wish, and I had it too. But thinking it over I would rather leave it as it is.
Usually you should minimize the number of dimensional constraints and rather use other geometric ones like = . Being able to position the Sketcher dimensions directly to the drawing would make you think differently but sketching is not drawing, you should think in terms of geometry like symmetry, equality, tangents etc.

[paullee]

I see good reasons for the wish, and I had it too. But thinking it over I would rather leave it as it is.
Usually you should minimize the number of dimensional constraints and rather use other geometric ones like = . Being able to position the Sketcher dimensions directly to the drawing would make you think differently but sketching is not drawing, you should think in terms of geometry like symmetry, equality, tangents etc.

Hi, I think there maybe difference between peoples modelling e.g. mechanical part and building, for the latter case dimensions are added based on ergonomic requirements, sometimes on geometric requirements (perpendicular, symmetry etc.), less of mathematical (modern architecture / building less relying on rule of golden section, xxx series etc.). So I find I need a lots of length / distance constraints