create a view of lofted 714 dof airfoil sketches

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louisgag
Posts: 75
Joined: Fri Jan 17, 2020 9:59 am

create a view of lofted 714 dof airfoil sketches

Post by louisgag »

Hello,
I've been trying to get a view of a loft which is based on sketches that have many degrees of freedom:
testTechDrawLoft_shaded.png
testTechDrawLoft_shaded.png (23.18 KiB) Viewed 1820 times
I always end up having way more lines than what I want, for example:
testTechDrawLoft_techdraw.png
testTechDrawLoft_techdraw.png (13.15 KiB) Viewed 1820 times
I'm attaching the FreeCAD document.

My workaround had been to manually remove the extra edges in Inkscape to get something like this:
testTechDrawLoft_inkscape.png
testTechDrawLoft_inkscape.png (11.96 KiB) Viewed 1820 times
Maybe there is a simpler way I am not aware of?
Kind regards,
-Louis

edit: adding info:
OS: Ubuntu 20.04.3 LTS (ubuntu:GNOME/ubuntu)
Word size of FreeCAD: 64-bit
Version: 0.20.
Build type: Release
Branch: unknown
Hash: bc90f4480b16eae1de05ea6d7e6ec322553684a8
Python version: 3.8.10
Qt version: 5.12.8
Coin version: 4.0.0
OCC version: 7.5.2
Locale: C/Default (C)
Attachments
testTechDrawLoft.FCStd
(282.99 KiB) Downloaded 23 times
Last edited by louisgag on Fri Dec 03, 2021 8:25 am, edited 1 time in total.
chrisb
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Re: create a view of lofted 714 dof airfoil sketches

Post by chrisb »

FreeCAD-info? Did you try latest 0.20?
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chrisb
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Re: create a view of lofted 714 dof airfoil sketches

Post by chrisb »

Had a look in 0.20: It's not the degrees of freedom, it's the number of points. You may consider to ad an additional sketch with the information you want.
I will give it a try later.
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louisgag
Posts: 75
Joined: Fri Jan 17, 2020 9:59 am

Re: create a view of lofted 714 dof airfoil sketches

Post by louisgag »

Hi Chrisb,
I'm using the freecad daily (0.20)
thanks,
-Louis
chrisb
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Re: create a view of lofted 714 dof airfoil sketches

Post by chrisb »

Here is an example with two helper sketches. For the screenshot I have adjusted the vertex size.
SnipScreenshot-6fcb46.png
SnipScreenshot-6fcb46.png (14.56 KiB) Viewed 1715 times
Attachments
testTechDrawLoft_cb.FCStd
(239.17 KiB) Downloaded 23 times
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
louisgag
Posts: 75
Joined: Fri Jan 17, 2020 9:59 am

Re: create a view of lofted 714 dof airfoil sketches

Post by louisgag »

thanks, that works but implies working manually.
Is there an automatic option?
edit: I mean, I am doing this on a much more complex assembly and would gladly avoid doing each subpart by hand 8-)
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Shalmeneser
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Re: create a view of lofted 714 dof airfoil sketches

Post by Shalmeneser »

If your object has edge, TechDraw will give you what you give him.
Use B-spline instead of polyline ?
domad
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Re: create a view of lofted 714 dof airfoil sketches

Post by domad »

Greetings to the Community!
For modeling if you don't want or can't use the b-spline, here's an alternative in an animation
Attachments
testTechDrawLoft.FCStd
(354.97 KiB) Downloaded 16 times
testTechDrawLoft.gif
testTechDrawLoft.gif (974.04 KiB) Viewed 1581 times
louisgag
Posts: 75
Joined: Fri Jan 17, 2020 9:59 am

Re: create a view of lofted 714 dof airfoil sketches

Post by louisgag »

thanks for your suggestions.
the problem with the spline is that it won't allow lofting anymore, at least not in the part workbench
as for the video, thanks for sharing it, but it still remains more work than editing the final svg in inkscape and if I change something in the design then I have to redo all these steps.
chrisb
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Re: create a view of lofted 714 dof airfoil sketches

Post by chrisb »

In my proposal you can at least move the profiles around. Due to topological naming problems it can break if you add or remove lines from the polyline though.
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