Sketch constraint applied to a segmented circle

[John_C_Hansen]

While working on my desk project I started over attempting to create a fully constrained sketch for the desktop.  I can't seem to get this sketch to be fully constrained. I have tried applying dimensions and angles to every line that touches this arc.

[g-andresen]

Hi,

That's exactly what you shouldn't do.
Whenever several elements meet at one point, this can lead to problems.
Remove dimensions, test whether elements can be moved even though they appear to be fixed and bring moved elements back into relation, e.g. through a coincidence.

günther

[TrippyLighting]

Too complicated 😉

Check out my last post to your other thread.

[John_C_Hansen]

While I  appreciate the fact that you achieved a constrained  sketch  by manipulating the segments that were shown, I drew this sketch based upon my design intent. The radius of this arc is 45 inches from a point that was defined based on a fixed distance from the origin. The bottom of that arc was defined as a line parallel to the X axis that was 45 inches in length. The  the length and angles of those 2 lines  that establish the location of the horizontal base of the arc segment was drawn from a point  based upon my design intent. Whereas your method of solving this issue was based upon manipulating lines that had already been laid down based upon a design intent. So, how are we as designers supposed to translate our design intent through a sketch that requires repositioning lines that were accurately drawn from the beginning. Those construction lines were  sketched based upon well understood geometric principles. Whereas the method you used of creating  coincident constraints, which were made when I drew the lines  of a specific length and established angles for those lines  in reference to a horizontal line.  Drawing elements of a sketch and then moving them does not accomplish the design intent that  I envisioned.  Also, notice that in the resulting sketch, The radius of the arc segment is not identified and is a critical part of the design intent.

What I'm trying to say  is that drawing a line in space and then moving the line to a position is challenging for me when all my life I have started lines from a point of origin drawn at an angle for a set distance.

[TrippyLighting]

Please do not use the quick reply function at the bottom of a thread, as it looks like you are replying to yourself.

Reply to a specific post.

I am not entirely sure you are replying to me or to @g-andresen 😉

In general, you need to forget and re-learn some of the things you're used to. You are NOT working with a 2D design software!

[g-andresen]

Hi,

I don't manipulate anything, but analyse the sketch on the basis of distinctive features.

Since I don't know the history of this sketch, I will first try to find obvious errors.
These are, for example, white dots that signalise open vectors.
When trying to connect these, I will then gradually come across further problem areas.

In future, please reply directly to individual posts and not to the entire thread via Post Reply.
In this case, you have replied to yourself.

günther

[g-andresen]

Hi,

I think this screencast makes it clearer that, as I wrote above, there were missing assignments.
If you then create dimensions, you cannot recognise which point they are assigned to.

günther

[Christoph_360]

Hello

---

@John_C_Hansen  wrote:

The radius of this arc is 45 inches from a point that was defined based on a fixed distance from the origin. The bottom of that arc was defined as a line parallel to the X axis that was 45 inches in length. The length and angles of those 2 lines  that establish the location of the horizontal base of the arc segment was drawn from a point  based upon my design intent.

I tried to depict what you describe here.

Thanks

Christoph