A tough nut for the solver

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drmacro
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Re: A tough nut for the solver

Post by drmacro »

Batucada wrote: Sun Aug 14, 2022 5:06 pm
drmacro wrote: Sun Aug 14, 2022 3:15 pm All I did was open the sketch and select edges and attempt to move them. And, they moved, thus the vertexes were not marked coincident.
After all, I'm always looking for an excuse for not seeing it.
I will do the wobble test soon, I promise....

But if you are concentrated on not making a mistake, then you are also rock-solidly convinced at the end that you really haven't made a mistake. The problem is obviously that the coincidences are not displayed. It would be nice if there were an inspection function, you select an element and then you get the constraints that belong to that element. Well, Christmas is coming soon, so maybe we can make a wish.
As I said, the inspection function is Sketch>Validate sketch.

You can avoid nearly all missing coincidents by using the polyline tool, trim tool, etc. They automagically make the vertexes coincident.

The other thing is to completely sketch and check/fix coincidents before using any dimensional constraints.

Using these techniques I have not created a missing coincident in a very long time. :mrgreen:
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
Batucada
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Re: A tough nut for the solver

Post by Batucada »

Bance wrote: Sun Aug 14, 2022 5:09 pm Image

No need to wait......

Sketcher_SelectConstraints
It's really nice to point out such a tool to me. It was an occasion to finally have a look at the tools in the Sketcher toolbar. I think now it would make sense to book an introductory course again. At the beginning, like probably many other users, I had neither eyes nor ears for these many details.
drmacro
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Re: A tough nut for the solver

Post by drmacro »

Batucada wrote: Sun Aug 14, 2022 5:37 pm
Bance wrote: Sun Aug 14, 2022 5:09 pm Image

No need to wait......

Sketcher_SelectConstraints
It's really nice to point out such a tool to me. It was an occasion to finally have a look at the tools in the Sketcher toolbar. I think now it would make sense to book an introductory course again. At the beginning, like probably many other users, I had neither eyes nor ears for these many details.
@chrisb has graciously provided the Sketcher Lecture...70+ pages detailing the Sketcher...time for some light reading? ;)
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
Batucada
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Re: A tough nut for the solver

Post by Batucada »

yes, I have read @chrisb's Sketcher tutorial, but in German, probably I should follow his hint and have a look at the English version.
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Shalmeneser
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Re: A tough nut for the solver

Post by Shalmeneser »

1) the 1st rule is to keep all vertexes upon each other.
2) Tangency (via Polyline)
3) Vertical / horizontal
It's possible here to shake the sketch (moving random line) to verifiy the coincidence.

4) other geometric constraints (point on object, parallelism, equality)
shake again

5) dimensions

[Trim tool need to be checked each time because it usually kills coincidence.]
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drmacro
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Re: A tough nut for the solver

Post by drmacro »

Shalmeneser wrote: Sun Aug 14, 2022 7:27 pm ...
[Trim tool need to be checked each time because it usually kills coincidence.]
That has never happened to me in hundreds of sketches and hundreds of trims... :roll:
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
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