Problems overwriting construction lines

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Shalmeneser
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Re: Problems overwriting construction lines

Post by Shalmeneser »

GeneFC wrote: Wed Oct 20, 2021 12:01 am Don't do that!

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

Gene
Why ?
GeneFC
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Re: Problems overwriting construction lines

Post by GeneFC »

Shalmeneser wrote: Wed Oct 20, 2021 5:27 am Why ?
You were the one who brought up master sketch in this thread. I think it is preferred to bring in the master sketch as a copy rather than an "external". I avoid "external" like the plague. Probably OK for a sketch, but often leads to TNP if used with a solid.

Your choice.

Gene
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Shalmeneser
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Re: Problems overwriting construction lines

Post by Shalmeneser »

GeneFC wrote: Wed Oct 20, 2021 2:13 pm I think it is preferred to bring in the master sketch as a copy rather than an "external".
Sketcher_CarbonCopy and Sketcher_External have problems and nothing is perfect.
  1. If you suppress the link, the link is suppressed and changes will not follow.
  2. If you keep link, suppressing it in the original sketch kill it in the copy.
  3. It's not written in the new sketch that you are 'copying' from other sketch. 'External' is explicit.
  4. In 'copy', you need sometimes to keep a lot of material from original sketch, obscuring your purpose.
  5. If you modify a lot your first sketch, 'copy' will not follow.
    'External' will break but if you use the minimal set of 'externals', modification could be possible.
I avoid "external" like the plague. Probably OK for a sketch, but often leads to TNP if used with a solid.
* Ok upon sketch : ok
* Not upon solid : ok
The solid has more chance to change than sketches.
I think it is preferred to bring in the master sketch as a copy rather than an "external".
Thank you for sharing this idea. Allways good dialog.
I need to think more about it.
GeneFC
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Re: Problems overwriting construction lines

Post by GeneFC »

Shalmeneser wrote: Wed Oct 20, 2021 5:07 pm [*] If you suppress the link, the link is suppressed and changes will not follow.
Yes, I noted that as a feature. :mrgreen:

Gene
chrisb
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Re: Problems overwriting construction lines

Post by chrisb »

CarbonCopy remains stable as long as the dimensional constraints remain. With the current technique, the constraints can even survive deleting a geometric element to which they are attached. But if you e.g. replace a dimension with an equality constraints, the CarbonCopy in general goes havoc.

External geometry doesn't care about constraints, but if you remove a geometric element or rearrange the sketch too heavily, the external references go havoc.
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