Problems overwriting construction lines

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Shalmeneser
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Re: Problems overwriting construction lines

Post by Shalmeneser »

Vagulus wrote: Sun Oct 17, 2021 10:35 pm Thanks, Shalmeneser, but that's not the issue. The Arc you are overwriting is not constrained so your new arc (drawn unconstrained over the old arc) does not raise a 'redundant constraint' warning.
The new arc Is constrained but the last vertex is not coincident with any vertex, just at the same (computed) place.

You can also create the arc :
* any center
* a vertex of the first arc
* the other vertex of the first arc
* equality on the radius of the two arcs
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Shalmeneser
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Re: Problems overwriting construction lines

Post by Shalmeneser »

GeneFC wrote: Sun Oct 17, 2021 11:53 pm However, I question the style of sketching construction geometries and then retracing exactly over those construction geometries with real geometries. Any time one completely covers an underlying structure there could be issues.

I use construction geometries to outline limits and provide convenient attachment points for real geometries. I almost never trace over and obscure an entire construction feature.
When you use external geometry from a master sketch, you need to redraw over it.
We'd need a tool to directly draw an external geometry (like if you get vertex external geometry then draw upon).
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Shalmeneser
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Re: Problems overwriting construction lines

Post by Shalmeneser »

An arc (5 DOF) using 3 constrained vertex (3x2=6 DOF) cause overconstrain.
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Re: Problems overwriting construction lines

Post by GeneFC »

Shalmeneser wrote: Mon Oct 18, 2021 12:52 pm When you use external geometry from a master sketch, you need to redraw over it.
Not really. An arc is a well-defined shape. No need to trace directly. Or you can just use the arc that was imported. I often do that sort of thing. It is usually best to break the link that came with the external geometry.

As I said it is a matter of style. It works either way as long as one is careful.

Gene
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Shalmeneser
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Re: Problems overwriting construction lines

Post by Shalmeneser »

GeneFC wrote: Mon Oct 18, 2021 1:43 pm ... Or you can just use the arc that was imported [with external geometry].
How do you use the arc ? (I've got problem to understand everything in our dialog.)
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Re: Problems overwriting construction lines

Post by Vagulus »

domad wrote: Mon Oct 18, 2021 11:35 am With the (Win8) FC 0.20-25997 (standalone) version ...
You're one up on me! :lol:
The FC download page lists v. 0.19.2 as the latest stable version.
"It is much harder to simplify than to complicate."
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Re: Problems overwriting construction lines

Post by domad »

Vagulus wrote: Mon Oct 18, 2021 9:29 pm .......
.... even the development versions are very stable and offer sufficient "peace of mind", therefore I strongly advise you to use these versions (updated and corrected weekly) in particular the standalone ones because they do not require installation and dependencies are all satisfied, plus they are not "dirty" the register.
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Re: Problems overwriting construction lines

Post by GeneFC »

Shalmeneser wrote: Mon Oct 18, 2021 4:41 pm How do you use the arc ?
When a sketch is brought in as a carbon copy all of the individual elements, lines, circles, arcs, etc. are brought in just like they were in the original sketch. You can modify, delete, move, or whatever. The elements can be converted between construction and real as desired.

I often break the links that come along with some constraints so that there is no longer a direct back-reference to the original. You can do this by attempting to edit, say, a dimension. Enter the constraint edit mode, click the expression icon, select clear, and then when back in the dialog just select OK. The value that was the result of the expression will be the new fixed dimension.

Of course you can leave the back-references if you want to keep the parametric behavior.

Works great.

Gene
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Shalmeneser
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Re: Problems overwriting construction lines

Post by Shalmeneser »

GeneFC wrote: Tue Oct 19, 2021 6:27 pm When a sketch is brought in as a carbon copy ...
I'm not speaking about Sketcher_CarbonCopy, but about Sketcher_External.
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Re: Problems overwriting construction lines

Post by GeneFC »

Don't do that!

Bring in the master sketch as a carbon copy, not as an external.

Gene
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