Bug Report - Part Workbench - Revolve

[r-frank]

Hello.

I just found out something which is not OK (at least not for me ...)
Using 0.15.4527 on WIndows 7 - 64 bit.

If you draw one closed shape with sketcher and use Revolve in Part Workbench with "create solid" ticked,
you get a solid.
If you draw more than one closed shapes, use revolve with "create solid" ticked, you won't get solids.
You will get shell objects.

Part Design would refuse Revolution with more than one closed shape.
Part should show the same behaviour or should show a warning and disable the "create solid" command
> whatever you think is more appropriate or easier to implement

Look here for proof:

Revolve_Part_Workbench-Bug.jpg (352.91 KiB) Viewed 2561 times

Thanks for your time.

Roland

[jmaustpc]

could you please post an example file?

[ulrich1a]

I can confirm the behavior of making shells with Part revolve.

Ulrich

OS: Debian GNU/Linux 8.0 (jessie)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.15.4570 (Git)
Branch: remotes/origin/master
Hash: d89d1808b71a6a1eea2e4ef50516b2feedef7135
Python version: 2.7.8
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17-dev

[ulrich1a]

I would think, Part-Design-revolve fails because of the Part-revolution-error.

Ulrich

[r-frank]

could you please post an example file?

Sure ... see attachment.

Using such a sketch (or even the same) with Revolution in Part Design will result in an invalid shape.
[As said above ... used 0.15.4527 on Windows 7 - 64bit]
Error Message:

Part-Design-Error.jpg (20.46 KiB) Viewed 2521 times

Roland

[r-frank]

Reported on Mantis as Issue #1969.

[quick61]

What you are trying to do here is create 2 separate parts with one action. The tool should not allow one to create 2 separate solids. If it did, it would need to create a Compound, like Array. Sense Part Workbench works with shells, as opposed to Part Design which only deals with solids, Part > Revolve will allow shells, as they could be part of a more complex solid being created in further operations. IMO this is not a bug, but working just as it should. Maybe a feature request to allow Part > Revolve to 'Make Compound Solid' from such Sketches / Draft objects might be more appropriate than calling it a bug.

Mark

[r-frank]

Well Mark, you've got a point ...
I was also thinking quite some time if it is more a bug or a feature request ...

At least we agree on that: Either the tool should refuse the action or revert
to make a shell WITH WARNING MESSAGE or similar ...

Roland

[Kunda1]

@shoogen writes in http://freecadweb.org/tracker/view.php?id=1969#c5801

we could add a check if that every shell, face, edge or vertex must be references from solids. If that would not be the case we could raise an exception. But we should not change the behavior, if the solid flag is set to false.

[Willem]

In my opinion the revolve function needs to be modified. I have an example from this forum https://forum.freecadweb.org/viewtopic.php?f=3&t=19936. It is a design for a fan. A patharray is made from a circle, the array with 25 circles is revolved, the revolve succeeds but the created toruses are not solid and this is a situation for a normal design where you may expect that these toruses can be solid

Fan-1.png (141.3 KiB) Viewed 2030 times

Freecad files are available in the topic