Loft to a Point

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uofmrob
Posts: 17
Joined: Thu Sep 29, 2022 10:30 pm

Loft to a Point

Post by uofmrob »

Hi Everyone,
I'm trying to figure some things out. I don't have a specific need for what I'm trying to do, but I'm trying to learn how to use some things in FreeCAD. I've seen some forum posts and looked in the directions and they all seem to suggest that it's possible to make an additive loft in part design from a sketch to a vertex. I've tried to go from a sketch to a datum point, a point in a sketch or a point from a draft and none of them are able to be used to create an additive loft. I can get it to work by having a sketch with some profile for the base and then a second sketch with a circle that has a very small radius, but if it's a point of any kind, it isn't working. This is what it says in the additive loft documentation:
Vertices can only be either the start or end of a loft. Otherwise the loft body would consist of two solids connected at a single point. This would violates the CAD kernel's definition of a 3D object.
How can I create a "vertex" that can serve as the beginning or end of an additive or subtractive loft?
Thanks!
chrisb
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Joined: Tue Mar 17, 2015 9:14 am

Re: Loft to a Point

Post by chrisb »

Hi and welcome to the forum!

Create a sketch with only a point. Make sure it is real and not construction geometry.
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Syres
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Joined: Thu Aug 09, 2018 11:14 am

Re: Loft to a Point

Post by Syres »

Just to expand on chrisb's statement, Point is the only geometry that is created as Construction by default (displayed red in Sketcher 3D space by default), the user then has to select it and click the Toggle Construction button to make it real geometry (displayed white in Sketcher 3D space by default). I'm sure there was a discussion in the past as to why point behaves differently to line etc, I personally still use Draft>Point as it's so easy to use.
mario52
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Posts: 4673
Joined: Wed May 16, 2012 2:13 pm

Re: Loft to a Point

Post by mario52 »

Hi

try Macro_D_Un_Jour_Raccord_2_Objects_By_Its_Faces (Part workbench)

point to face
pointToFaceLoft00.png
pointToFaceLoft00.png (18.62 KiB) Viewed 526 times

mario
Maybe you need a special feature, go into Macros_recipes and Code_snippets, Topological_data_scripting.
My macros on Gist.github here complete macros Wiki and forum.
uofmrob
Posts: 17
Joined: Thu Sep 29, 2022 10:30 pm

Re: Loft to a Point

Post by uofmrob »

Great! Thanks, everyone for the quick replies! I tried again by switching the point in a sketch to a normal point (don't know how I missed that) and it still didn't work in 0.19 (that's the latest stable in Linux from the PPA) and also in the realthunder fork that fixes the topological naming problem. But when I tried the 0.20 appimage, it worked fine. It seems that there was maybe a little bug that got fixed in the most recent release.
Thanks again!
drmacro
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Joined: Sun Mar 02, 2014 4:35 pm

Re: Loft to a Point

Post by drmacro »

uofmrob wrote: Fri Sep 30, 2022 1:05 pm Great! Thanks, everyone for the quick replies! I tried again by switching the point in a sketch to a normal point (don't know how I missed that) and it still didn't work in 0.19 (that's the latest stable in Linux from the PPA) and also in the realthunder fork that fixes the topological naming problem. But when I tried the 0.20 appimage, it worked fine. It seems that there was maybe a little bug that got fixed in the most recent release.
Thanks again!
No, it just didn't work in 0.19. The capability was added in 0.20 if I remember correctly.

Also, I think the latest release is 0.20.1. The PPA may be a bit outdated.

Edit: I think it actually did work in Part workbench, but, not Part design in 0.19.
Last edited by drmacro on Fri Sep 30, 2022 1:30 pm, edited 1 time in total.
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uofmrob
Posts: 17
Joined: Thu Sep 29, 2022 10:30 pm

Re: Loft to a Point

Post by uofmrob »

Thanks for the info!
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