How to draw a line perpendicular from a point to a face

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ranila
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Joined: Wed Dec 01, 2021 5:11 pm

How to draw a line perpendicular from a point to a face

Post by ranila »

Hello,
is it possible to draw a line perpendicular from a point in 3D to a face or the plane of that face?
Or to put it in other words, is there a corresponding command as "snap perpendicular to an edge in 2D" transformed into 3D as "snap perpendicular to a face or plane"?
drmacro
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Re: How to draw a line perpendicular from a point to a face

Post by drmacro »

What is the use case for such a thing?

Just curious.
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
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Roy_043
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Re: How to draw a line perpendicular from a point to a face

Post by Roy_043 »

AFAIK you need to use a workaround:
  1. Align the Draft working plane with the face (Draft_SelectPlane).
  2. Pick the first point.
  3. For the second point press Z to constrain and snap to a point (f.e. endpoint of edge, center) of the face.
ranila
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Re: How to draw a line perpendicular from a point to a face

Post by ranila »

@drmacro: just wondering and playing around. It's my way of thinking, when there is something of that kind in 2D, there must be an equivalent in 3D. Just the same task, but +1D.

I know you FC guys live in a total different extruding-universe. Me I'm coming from 2D construction and eventually will learn the new thinking paradigma. But just for curiosity and playing with 3D stuff as transforming geodesic solids into real struts construction I stumble upon those kind of perpendicular questions, which one of them will come as a new topic ;)

@ Roy_043: well, that's a nice one, not that intuitiv as "snap perpendicular to a face/plane" - but quite a handsome workaround.

Big thanx to you!!
drmacro
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Re: How to draw a line perpendicular from a point to a face

Post by drmacro »

ranila wrote: Tue Dec 07, 2021 6:18 pm @drmacro: just wondering and playing around. It's my way of thinking, when there is something of that kind in 2D, there must be an equivalent in 3D. Just the same task, but +1D.

...
I avoid drawing anything in Draft. The Draft workbench has a set of tools like upgrade to sketch and the array tools that are invaluable, but, I find it's drawing tools incomprehensible.

...like the method discussed here. :mrgreen:
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
domad
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Re: How to draw a line perpendicular from a point to a face

Post by domad »

ranila wrote: Tue Dec 07, 2021 5:21 pm ........
Greetings to the Community!
.... in addition to the classic tools available in the "Draft" Wb (lines, snaps, choice of work plans, etc.) already mentioned in the previous replicas, the powerful "Work Features" Wb is available in the "Addon manager".
In the following * .gif a taste of the tools (unfortunately not all tools work properly with the latest versions of FC, an update/adaptation would be desirable)
Attachments
Work Feautures.gif
Work Feautures.gif (766.41 KiB) Viewed 1372 times
chrisb
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Re: How to draw a line perpendicular from a point to a face

Post by chrisb »

ranila wrote: Tue Dec 07, 2021 6:18 pm It's my way of thinking, when there is something of that kind in 2D, there must be an equivalent in 3D. Just the same task, but +1D.
Sad to say, but I'm afraid you are on the completely wrong track. Modeling in 3D is not at all just a bit more complicated than 2D. It needs a very different way of thinking. So free your mind, work through some PartDesign Tutorials, and restart from zero.
Starting from your level of 2D knowledge is starting below zero (been there, done that!).
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
ranila
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Re: How to draw a line perpendicular from a point to a face

Post by ranila »

Hi chrisb,
given your 38T post, I surely cannot help but give in into your advice. It's just, that I have no clue how to do it in PartDesign, as I want to construct (or find) geodesic dome structures, not knowing about length and angles of struts, but to come from an icosahedron and trying to fit struts into its shell sphere. Knowing all length and angles I think I could follow Ulrich1a (https://forum.freecadweb.org/viewtopic. ... =10#p56755) to build up a dome. But I want to fiddle with it, flatten the top pentagon, bring in doors and windows and stuff, resulting in new unforseen geometry. And all this should be done within PartDesign? Hard to believe, but you are the expert!
drmacro
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Re: How to draw a line perpendicular from a point to a face

Post by drmacro »

ranila wrote: Tue Dec 07, 2021 11:14 pm Hi chrisb,
given your 38T post, I surely cannot help but give in into your advice. It's just, that I have no clue how to do it in PartDesign, as I want to construct (or find) geodesic dome structures, not knowing about length and angles of struts, but to come from an icosahedron and trying to fit struts into its shell sphere. Knowing all length and angles I think I could follow Ulrich1a (https://forum.freecadweb.org/viewtopic. ... =10#p56755) to build up a dome. But I want to fiddle with it, flatten the top pentagon, bring in doors and windows and stuff, resulting in new unforseen geometry. And all this should be done within PartDesign? Hard to believe, but you are the expert!
The Diamonds and Polyhedrons workbench maybe? (But that does create a Part workbench object, so not Part Design workbench...)
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
chrisb
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Re: How to draw a line perpendicular from a point to a face

Post by chrisb »

I have lead you on the wrong track. I had meant to look at these tutorials to understand the very basics of FreeCAD and not in order to use PartDesign for the dome model.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
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