[Solved] Need help recreating a simple shape

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pathfinder
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Re: Need help recreating a simple shape

Post by pathfinder »

thomas-neemann wrote: Fri Oct 22, 2021 1:55 pm
here is a possibility
Thanks for your answer.

What I probably forgot to mention is that I already have the shape as a mesh and want to rebuild as a solid; I could just transform what I have to a solid (I know the way you've shown). The issue here is that the many polygons make working with it a real pain and can throw off the Path tools (although they've gotten far better at dealing with this kind of stuff even in the last few weeks).

That's why I want to rebuild this shape as a solid in the first place; so I can work with it as a solid.
drmacro
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Re: Need help recreating a simple shape

Post by drmacro »

I noted that the geometry in the file @thomas-neeman posted didn't pass geometry check (in master 0.20, was it created in linkstage3???)

Just for another take on this (couldn't pass up the challenge :mrgreen: )...somewhat low level, less steps, but, the result is valid solid:
Snip macro screenshot-e3e2f4.png
Snip macro screenshot-e3e2f4.png (94.1 KiB) Viewed 1211 times
Attachments
SweepShapeExample-4.FCStd
(236.27 KiB) Downloaded 24 times
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
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Shalmeneser
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Re: Need help recreating a simple shape

Post by Shalmeneser »

Pipe with Frenet Fixed at the corners (and some tricks but TNP).

Code: Select all

 └ Body (Body)
    ├ Pad (Pad)
    │  └ Sketch (Sketch)
    ├ AdditivePipe (AdditivePipe)
    │  ├ Sketch001 (Sketch)
    │  └ Sketch (Sketch)
    ├ Pocket (Pocket)
    │  └ Sketch002 (Sketch)
    ├ PolarPattern (PolarPattern)
    ├ AdditivePipe001 (AdditivePipe)
    │  ├ Sketch004 (Sketch)
    │  └ Sketch003 (Sketch)
    ├ PolarPattern001 (PolarPattern)
    └ Pocket001 (Pocket)
       └ Sketch (Sketch)
Attachments
SweepShapeExample_SHALM.FCStd
(127.3 KiB) Downloaded 23 times
Capture du 2021-10-22 18-10-51.png
Capture du 2021-10-22 18-10-51.png (29 KiB) Viewed 1192 times
Last edited by Shalmeneser on Fri Oct 22, 2021 5:40 pm, edited 1 time in total.
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Shalmeneser
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Re: Need help recreating a simple shape

Post by Shalmeneser »

drmacro wrote: Fri Oct 22, 2021 3:46 pm ...
Problem with the center line (not rounded).
Attachments
Capture du 2021-10-22 18-48-03.png
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Shalmeneser
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Re: Need help recreating a simple shape

Post by Shalmeneser »

(Less TNP ?)
Problem to unpad (=pocket) the 1s sketch. Don't understand why.
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SweepShapeExample_SHALM2.FCStd
(130.69 KiB) Downloaded 18 times
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pathfinder
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Re: Need help recreating a simple shape

Post by pathfinder »

Shalmeneser wrote: Fri Oct 22, 2021 4:13 pm Pipe with Frenet at the corners (and some tricks but TNP).

Code: Select all

 └ Body (Body)
    ├ Pad (Pad)
    │  └ Sketch (Sketch)
    ├ AdditivePipe (AdditivePipe)
    │  ├ Sketch001 (Sketch)
    │  └ Sketch (Sketch)
    ├ Pocket (Pocket)
    │  └ Sketch002 (Sketch)
    ├ PolarPattern (PolarPattern)
    ├ AdditivePipe001 (AdditivePipe)
    │  ├ Sketch004 (Sketch)
    │  └ Sketch003 (Sketch)
    ├ PolarPattern001 (PolarPattern)
    └ Pocket001 (Pocket)
       └ Sketch (Sketch)
This looks really good, but I have a hard time following your steps based on the file. What I got:

- you made the shape by creating a pipe
- you cut out the corners
- ?
- you replaced the corners with a shape that's the chamfer?

Sorry for being dense, it's just a lot going on that is new to me.

Also, what's TNP?
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Shalmeneser
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Re: Need help recreating a simple shape

Post by Shalmeneser »

pathfinder wrote: Fri Oct 22, 2021 5:30 pm
TNP = Topological_naming_problem

* 1st pipe for the global body
* pocket to cut one corner
* small pipe to complete this pocket (mode Fixed = the form doesn't turn, just sliding)
* Repetition×6 (PolarPattern)

The 1st pad is to keep one body during all the construction (corner cuts create 6 bodies without this precaution). It'll be suppressed at the end.

BTW, asking (politely) is key to undertanding.
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Re: Need help recreating a simple shape

Post by thomas-neemann »

pathfinder wrote: Fri Oct 22, 2021 2:05 pm ...That's why I want to rebuild this shape as a solid in the first place; so I can work with it as a solid.
here is a quick possibility

https://www.youtube.com/watch?v=dcyNubY3BgM


phpBB [video]
Gruß Dipl.-Ing. (FH) Thomas Neemann

https://www.youtube.com/@thomasneemann5 ... ry=freecad
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pathfinder
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Re: Need help recreating a simple shape

Post by pathfinder »

thomas-neemann wrote: Fri Oct 22, 2021 5:50 pm
here is a quick possibility
Oh yes, that's a neat trick, thanks!
Shalmeneser wrote: Fri Oct 22, 2021 5:46 pm
TNP = Topological_naming_problem

* 1st pipe for the global body
* pocket to cut one corner
* small pipe to complete this pocket (mode Fixed = the form doesn't turn, just sliding)
* Repetition×6 (PolarPattern)

The 1st pad is to keep one body during all the construction (corner cuts create 6 bodies without this precaution). It'll be suppressed at the end.
I'll need some time to process this, but I'm sure I can work with that, thanks!

And thanks for your explanation of TNP, I'm using RealThunders branch, which I think fixed it to some degree.

I'll mark this as solved, I' think I can figure it out from here.
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Shalmeneser
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Re: Need help recreating a simple shape

Post by Shalmeneser »

pathfinder wrote: Fri Oct 22, 2021 6:07 pm And thanks for your explanation of TNP, I'm using RealThunders branch, which I think fixed it to some degree.
I believe.
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