Problem with cosmetic lines in parametric models

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jb-workshop
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Joined: Fri Oct 23, 2020 6:11 am

Problem with cosmetic lines in parametric models

Post by jb-workshop »

G'Day

I created a body and a spreadsheet and used the configuration option of the spreadsheet, to generate all dimensions by selecting from the drop down menu in the properties pane of the body.

After verifying, that all selectable items could be created without generating an error from the solver/renderer, I selected a random item from the list and switched the workbench to "TechDraw". I inserted the "Default Page", inserted a "projection Group" and selected the desired views. In the top view, I "Added Cosmetic Thread Hole View".

Next I selected the top view and "Insert Section View" next to it. In that view, I also used "Add Cosmetic Thread Hole View", which also got used to show the dimension of the thread.

I saved the project, selected the body and choose another item of the parametric configuration. The window switched to the 3D body display. Going back to the TechDraw page window again, I noticed, that the views and the section view have adopted accordingly. Unfortunately, the cosmetic lines of the threads haven't changed and stayed in their original places, which gives an odd look.

I consider this a bug or at least a missing feature ;-)

See the attached model. I used the item "14-M10" to create the tech draw. The problem will get clear, if you use a much bigger T-slot nut, say "18-M16" or even bigger.

Bye

Jan
Attachments
nutenstein.FCStd.zip
parametric model of a T-slot nut
(60.59 KiB) Downloaded 15 times
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wandererfan
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Re: Problem with cosmetic lines in parametric models

Post by wandererfan »

jb-workshop wrote: Sun Jun 26, 2022 9:30 am I consider this a bug or at least a missing feature ;-)
Cosmetic features are not linked to anything so they don't keep up with changes to the model. There is a ticket for this issue #6127. No ETA at this time.
jb-workshop
Posts: 9
Joined: Fri Oct 23, 2020 6:11 am

Re: Problem with cosmetic lines in parametric models

Post by jb-workshop »

Hi Wanderfan,
wandererfan wrote: Sun Jun 26, 2022 1:27 pm There is a ticket for this issue #6127. No ETA at this time.
what a pitty. :cry:

I am an old guy. I was raised with technical drawings on good old transparency. Rapid prototyping was just starting to evolv. Therefore, a thread had those "cosmetic" lines and everything was good.

Nowadays, where you print a thread, instead of cutting it, I can understand, that your CAD model has to show the exact form of the thread. But I don't use prototyping and therefore would love to stay with the way I learned that things, i.e. using the "cosmetic" lines.

Same applies to creating the thread itself. In my world, I would draw a circle in the Parts Design workbench and would love to insert the measurement of M6 instead of the correct core bore on that hole. After padding the sketch, the resolver should know, that this hole is indeed a thread and TechDraw should know, that it has to draw a cosmetic line.

Furthermore, I was able to use parameters from the spreadsheet, but I am not sure, if I tackled the thread hole correctly. My method, described above, is capable to work with parameters, derived from the spreadsheet, where I can store the thread size as M12 (and even the pitch).

When extruding the hole sketch into a full 3D hole, you could choose a threaded "Profile" in the hole dialog, but you are not able, to link the following properties to spreadsheet data. When your model uses data from the spreadsheet, you have to use the core bore diameter or something similar. :|

So I daresay, that there is also some work to do.
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Shalmeneser
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Re: Problem with cosmetic lines in parametric models

Post by Shalmeneser »

:idea:
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Annotation 2022-06-28 090657.jpg
Annotation 2022-06-28 090657.jpg (39.64 KiB) Viewed 396 times
nutenstein_SHALM.FCStd
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