Failure to pad sketch drawn on a face which has the same shape

Post here for help on using FreeCAD's graphical user interface (GUI).
LeoTilson
Posts: 7
Joined: Fri Feb 17, 2017 1:19 am

Failure to pad sketch drawn on a face which has the same shape

Postby LeoTilson » Fri Feb 17, 2017 12:43 pm

Forum users, Thank you for considering this. It appears to be an edge-case.

OS: Windows 10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.6706 (Git)
Build type: Release
Branch: releases/FreeCAD-0-16
Hash: f86a4e411ff7848dea98d7242f43b7774bee8fa0
Python version: 2.7.8
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17

but it also appears on other versions of FreeCAD which are available to me, including version 0.17

Submitted as Bug Report here: https://freecadweb.org/tracker/view.php?id=2904


1) Open a new document in Part Design
2) New sketch - a teardrop. This consists of
a) An arc of about 270 degrees centred at the origin
b) A line with a horizontal constraint
c) A line with a vertical constraint
d) Where one of the lines joins the end of the arc include a tangential constraint.
3) Pad the sketch.
4) On the new face draw a second identical sketch. Choose the curved part of the sketch as external geometry.
5) Pad the second sketch

At this point we should have a teardrop twice the height of the first, but the model falls apart. The results of the operation are inconsistent, but, put succinctly, the Teardrop Explodes.

FirstPad.jpg
The first teardrop
FirstPad.jpg (198.54 KiB) Viewed 88 times


SketchOnFirstPad.jpg
Sketch drawn on top face
SketchOnFirstPad.jpg (309.99 KiB) Viewed 88 times


FirstAndSecondPads.jpg
Result of extruding the second sketch
FirstAndSecondPads.jpg (200.79 KiB) Viewed 88 times


Leo Tilson
Attachments
LeoTilsonTest2.FCStd
The FSCAD file
(9.28 KiB) Downloaded 7 times
chrisb
Posts: 1286
Joined: Tue Mar 17, 2015 9:14 am

Re: Failure to pad sketch drawn on a face which has the same shape

Postby chrisb » Fri Feb 17, 2017 3:19 pm

No problem here:
OS: Ubuntu 14.04.5 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.10101 (Git)
Build type: None
Branch: master
Hash: 99fa203f323927b0dd027420d4421b577b7420c3
Python version: 2.7.6
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17
Attachments
teardrop_cb.fcstd
(15.76 KiB) Downloaded 3 times
cox
Posts: 902
Joined: Wed Nov 26, 2014 11:37 pm

Re: Failure to pad sketch drawn on a face which has the same shape

Postby cox » Fri Feb 17, 2017 3:58 pm

Migrating the project file fixes the issue in :

OS: "Arch Linux"
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.9790 (Git)
Build type: Release
Branch: master
Hash: 294b2308d660a4aae11e90ec22f96ca56190bcd1
Python version: 2.7.13
Qt version: 4.8.7
Coin version: 3.1.3
OCC version: 6.9.1
Need help? Feel free to ask, but please read the guidelines first
User avatar
Kunda1
Posts: 537
Joined: Thu Jan 05, 2017 9:03 pm

Re: Failure to pad sketch drawn on a face which has the same shape

Postby Kunda1 » Fri Feb 17, 2017 4:08 pm

cox wrote:Migrating the project file fixes the issue

What does this mean?
User avatar
sgrogan
Posts: 2881
Joined: Wed Oct 22, 2014 5:02 pm

Re: Failure to pad sketch drawn on a face which has the same shape

Postby sgrogan » Fri Feb 17, 2017 4:18 pm

Kunda1 wrote:What does this mean?

See duplicate thread https://forum.freecadweb.org/viewtopic.php?f=3&t=20721
cox
Posts: 902
Joined: Wed Nov 26, 2014 11:37 pm

Re: Failure to pad sketch drawn on a face which has the same shape

Postby cox » Fri Feb 17, 2017 4:44 pm

Kunda1 wrote:
cox wrote:Migrating the project file fixes the issue

What does this mean?


After opening the file in 0.17 dev the model is corrupted as explained in OP's post. Since this model was made in 0.16 it is possible to use Partdesign:Migrate function to upgrade the model to 0.17. Using this function fixes the model according to OP's expectations.
Need help? Feel free to ask, but please read the guidelines first