In Techdraw, Dimensions getting changed after changing view scale to 2:1 from 1:1.

Discussions about the development of the TechDraw workbench
Sanjay.T
Posts: 20
Joined: Wed Feb 17, 2021 4:46 pm

Re: In Techdraw, Dimensions getting changed after changing view scale to 2:1 from 1:1.

Postby Sanjay.T » Tue Mar 09, 2021 4:20 pm

Thank you Edi, Yes part is assembled in this file. So Will I have to live with this issue or is there any solution ? Many thanks.
chrisb
Posts: 37271
Joined: Tue Mar 17, 2015 9:14 am

Re: In Techdraw, Dimensions getting changed after changing view scale to 2:1 from 1:1.

Postby chrisb » Tue Mar 09, 2021 5:01 pm

edi wrote: Tue Mar 09, 2021 1:01 pm It is a kind of the 'topo naming problem'. If the part has scale 1.0 the upper circle (diameter 16) is Edge34. After changing the scale to 2.0 the same circle is Edge26. The dimension keeps connected to Edge34.

I think it happenes, because your part has been imported from somewhere (a2plus ?) and therefore is a foreign object for TechDraw.
So I guess that TechDraw isn't scaling himself, it uses a scaled model and derives a drawing from it. Then this issue can occur with native FreeCAD objects as well.
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edi
Posts: 320
Joined: Fri Jan 17, 2020 1:32 pm

Re: In Techdraw, Dimensions getting changed after changing view scale to 2:1 from 1:1.

Postby edi » Wed Mar 10, 2021 12:56 pm

Sanjay.T wrote: Tue Mar 09, 2021 4:20 pm So Will I have to live with this issue or is there any solution ?
I recommend generating technical drawings in three steps:

1. create all drawings (views, sections, details) in the required scale and position them in the template.
2. add additional objects (center lines, cosmetic threads etc.)
3. add dimensions, annotations etc.

If you respect this 3 step rule your issue will not occure

Nevertheless a question: Why do you need A2Plus to create a single part? It can be done in Part-WB or PartDesign-WB.
Sanjay.T
Posts: 20
Joined: Wed Feb 17, 2021 4:46 pm

Re: In Techdraw, Dimensions getting changed after changing view scale to 2:1 from 1:1.

Postby Sanjay.T » Wed Mar 10, 2021 5:52 pm

edi wrote: Wed Mar 10, 2021 12:56 pm
Sanjay.T wrote: Tue Mar 09, 2021 4:20 pm So Will I have to live with this issue or is there any solution ?
I recommend generating technical drawings in three steps:

1. create all drawings (views, sections, details) in the required scale and position them in the template.
2. add additional objects (center lines, cosmetic threads etc.)
3. add dimensions, annotations etc.

If you respect this 3 step rule your issue will not occure

Nevertheless a question: Why do you need A2Plus to create a single part? It can be done in Part-WB or PartDesign-WB.
Thanks Edi for the Steps, I wanted the model file to contain only the solid geometry, so assembled into a new file and created all the required drawing items in this separate file.
knutb
Posts: 2
Joined: Tue Mar 02, 2021 7:41 am

Re: In Techdraw, Dimensions getting changed after changing view scale to 2:1 from 1:1.

Postby knutb » Tue Mar 16, 2021 1:34 pm

This effect is somethink very basic and has nothing to do with a2plus or similar. I've described it in my post where there are no responses to yet:

https://forum.freecadweb.org/viewtopic.php?f=35&t=56191

Obviously names of objects are reorganitzed after changes and this brings the references of the dimensions into trouble.
karlp
Posts: 4
Joined: Tue Feb 02, 2021 1:18 pm

Re: In Techdraw, Dimensions getting changed after changing view scale to 2:1 from 1:1.

Postby karlp » Wed May 12, 2021 2:22 pm

Related, if create a techdrawing with a scale of 2:1, make it all nice, add dimensions, they show the expected (real) dimensions. If I then export to dxf, and open the file in qcad/librecad, and add a new dimension there, the new dimension is doubled. See eg: Image

I don't believe that should be the case?

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