TNP page offers datum plane solution that is not an optimal one.

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Bance
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TNP page offers datum plane solution that is not an optimal one.

Post by Bance »

The page above offers a solution for TNP that involves using datum planes.

Whilst I absolutely agree this is a way of mitigating TNP, it is not an optimal solution since sketches themselves can be attached and offset in exactly the same way.

This page is responsible for many users thinking that using datum planes to workaround TNP is the only way.

I would like to edit this page to better inform users of the options available.

I think that the proffered solution should not be on that page at all, it should rather be on the Feature Editing page under Advice for stable modelling.

Or at least it should be made clear that DP's are not the only solution.

What are your thoughts?
chrisb
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Re: TNP page offers datum plane solution that is not an optimal one.

Post by chrisb »

Bance wrote: Thu Nov 03, 2022 9:09 pm What are your thoughts?
Good idea. It probably deserves an own paragraph when not to use DatumPlanes (without offset on a main plane, DatumPlane attached itself to unstable geometry, ...)
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Roy_043
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Re: TNP page offers datum plane solution that is not an optimal one.

Post by Roy_043 »

Can the two pages be merged?
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onekk
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Re: TNP page offers datum plane solution that is not an optimal one.

Post by onekk »

Hello.

Maybe a different solution would be to make the "Advice for stable model" a separate page and link both in "TNP" and in "Feature Editing" pages, and eventually when needed, in other pages.

Regard

Carlo D.
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drmacro
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Re: TNP page offers datum plane solution that is not an optimal one.

Post by drmacro »

This point in the existing wiki page is just too subtle. It allows many readers to come away with the idea that simply using the Datum plane, in any way, will stop TNP. Experienced users will extrapolate that attaching the Datum to generated geometry (or sketch geometry that gets changed) is no good. But, the inexperienced reader doe not make the connection.

My attempts to change the wiki to stress such subtleties was rejected without discussion.
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Roy_043
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Re: TNP page offers datum plane solution that is not an optimal one.

Post by Roy_043 »

drmacro wrote: Fri Nov 04, 2022 9:36 am stress such subtleties was rejected without discussion.
You added a note that mostly repeated what was already said in the previous (!) sentence. I have reworded that previous sentence integrating what you added in your note. I do not see this as a rejection.

https://wiki.freecadweb.org/index.php?t ... id=1203305
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Re: TNP page offers datum plane solution that is not an optimal one.

Post by drmacro »

Roy_043 wrote: Fri Nov 04, 2022 9:57 am
drmacro wrote: Fri Nov 04, 2022 9:36 am stress such subtleties was rejected without discussion.
You added a note that mostly repeated what was already said in the previous (!) sentence. I have reworded that previous sentence integrating what you added in your note. I do not see this as a rejection.

https://wiki.freecadweb.org/index.php?t ... id=1203305
The point was, exactly that, to repeat the previous sentence to stress "NO GENERATED GEOMETRY".

It should also stress that Datums attached to changing sketch geometry is only marginally better.

These need to be explicit, else as I noted above, people read it as "oh I can just use Datum planes" and don't infer the details.
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Roy_043
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Re: TNP page offers datum plane solution that is not an optimal one.

Post by Roy_043 »

When addressing a classroom you can repeat a sentence, but to do so in a written text is strange IMO. You would have to change the wording then.
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Re: TNP page offers datum plane solution that is not an optimal one.

Post by drmacro »

It is quite common to emphasize a point in written text.

Admittedly, I was attempting to emphasize the point without making major changes to the page.

Maybe a table detailing the best to worst options or a list of best to worst.

The way it is now is not optimal.
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