Sheet Metal modeling - pad error with arc of ellipse

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Lars
Posts: 9
Joined: Sat May 05, 2018 10:39 am

Sheet Metal modeling - pad error with arc of ellipse

Postby Lars » Wed May 09, 2018 10:37 am

Dear all,
We are preparing a sheet metal part with bends, based on a padded 2D sketch. The 2D boundaries contain holes and an arc of ellipse and fails to pad for applying a thickness. I wonder if any user have faced a similar issue when applying the part design pad function - and how to overcome ? (When resolved, we also need to introduce a 90-degree bend to the arc of ellipse)

As I fail to attach files to posts, please find the file in the cloud drive here: https://rushfiles.one/client/publiclink ... HDkUf0zMb3


BR
Lars

FreeCAD metadata:

OS: Windows 10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.13519 (Git)
Build type: Release
Branch: releases/FreeCAD-0-17
Hash: 1a8b868018f45ea486c0023fdbfeb06febc1fb89
Python version: 2.7.14
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: Danish/Denmark (da_DK)
Best regards

Lars
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meme2704
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Location: Vosges

Re: Sheet Metal modeling - pad error with arc of ellipse

Postby meme2704 » Wed May 09, 2018 12:09 pm

Known problem, segments hangs on to the lines of construction, not in segment adjoining, you have a perfectly green, but open sketch
Now you wishes to have an edge vertical to the curve eliptique, it is not possible, you haves to takes your hammer and an anvil .Sorry :lol:
I have you to send the method to join a document, I put you to it again in copy
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Lars
Posts: 9
Joined: Sat May 05, 2018 10:39 am

Re: Sheet Metal modeling - pad error with arc of ellipse

Postby Lars » Sun May 13, 2018 7:52 pm

meme2704 wrote:
Wed May 09, 2018 12:09 pm
Known problem, segments hangs on to the lines of construction, not in segment adjoining, you have a perfectly green, but open sketch
Now you wishes to have an edge vertical to the curve eliptique, it is not possible, you haves to takes your hammer and an anvil .Sorry :lol:
I have you to send the method to join a document, I put you to it again in copy
Hello Meme,
Thank you for your reply, however, the endpoints of the arc of the ellipse are connected to the objects..
If this is insufficient, what would then be the trick to ensure the connection of the lines?
BR
/Lars
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Lars
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NormandC
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Location: Québec, Canada

Re: Sheet Metal modeling - pad error with arc of ellipse

Postby NormandC » Sun May 13, 2018 8:06 pm

Lars wrote:
Sun May 13, 2018 7:52 pm
however, the endpoints of the arc of the ellipse are connected to the objects..
The problem is as meme2704 said, the ellipse upper end is not connected to the vertical white line, it's connected to the horizontal construction line of the ellipse. To confirm this, delete the horizontal blue construction line, then pick the ellipse arc and move it.

You will see that rather than a coincident constraint, there is a point on object constraint between the ellipse and the white vertical line.
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NormandC
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Re: Sheet Metal modeling - pad error with arc of ellipse

Postby NormandC » Sun May 13, 2018 8:15 pm

To fix it:

  1. Delete the horizontal construction line
  2. Delete the Image point on object constraint
  3. With the mouse, draw a box over the point where the ellipse and the vertical line apparently meet: this will select both end points
  4. Create a point-to-point Image tangent constraint
  5. Add a Image horizontal distance constraint between the vertical blue construction line and the upper left corner of the profile.
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Lars
Posts: 9
Joined: Sat May 05, 2018 10:39 am

Re: Sheet Metal modeling - pad error with arc of ellipse

Postby Lars » Mon May 14, 2018 11:25 am

NormandC wrote:
Sun May 13, 2018 8:15 pm
To fix it:

  1. Delete the horizontal construction line
  2. Delete the Image point on object constraint
  3. With the mouse, draw a box over the point where the ellipse and the vertical line apparently meet: this will select both end points
  4. Create a point-to-point Image tangent constraint
  5. Add a Image horizontal distance constraint between the vertical blue construction line and the upper left corner of the profile.
Thank you Normand, grateful.
That did the trick :)
/Lars
Best regards

Lars
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meme2704
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Re: Sheet Metal modeling - pad error with arc of ellipse

Postby meme2704 » Mon May 14, 2018 4:18 pm

I don't send you the result "by hand" of yours project
I unfold the edges after bending it, but the curve side isn't unfold (impossible)
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