FreeCAD Forum

Hi, I have created a Sketch and want to build ArchWall upon it. I find I am stuck in following situation.

1. I try build ArchWall upon it, it return the Sketch has invalid shape - but i don't know what is wrong, see below.
2. I have a habit of upgrading the Sketch into Dwire, so I do it again though the ArchWall result would be different for a Sketch and Dwire. Now ArchWall could be created without problem upon the said Dwire (which still depending on the same underlying Sketch) .
3. I intend to do an ArchWall based on the Sketch (1 above) so that I get an perimeter wall. If the ArchWall is built upon the Dwire (face on), it become a volume.

Am i missing something?


OS: Linux
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.11009 (Git)
Build type: Unknown
Branch: master
Hash: 77386684fb76c0d91ea05cc6a0e005d5d8441d21
Python version: 2.7.13
Qt version: 4.8.7
Coin version: 3.1.3
OCC version: 6.8.0.oce-0.17

The result of the wall depends if the base shape is a Wire or a Face. If it's a wire, it gets first "thickened" to the given wall thickness, then extruded by the wall height value. If it is a face, it is understood that you are already giving it the footprint, and it is simply extruded upwards. When you have a draft wire, you can set its "MakeFace" property to false to prevent it from forming a face and make it behave as a wire instead.

yorik wrote:The result of the wall depends if the base shape is a Wire or a Face. If it's a wire, it gets first "thickened" to the given wall thickness, then extruded by the wall height value. If it is a face, it is understood that you are already giving it the footprint, and it is simply extruded upwards. When you have a draft wire, you can set its "MakeFace" property to false to prevent it from forming a face and make it behave as a wire instead.

Thanks! I understand it would be a solid volume if it is a Wire w/ face.

The current problem is, whether i use the underlying sketch, or the DWire w/ face Off, FC report it is an invalid shape.

I can't figure out what am i missing? Any topology not valid for ArchWall?

There is apparently something in that sketch that the DraftGeomUtils.offsetWire function doesn't like (it fails to produce a correct offset). I must think to switch to the new Part offset2D code, that will likely work better

Reference:

https://forum.freecadweb.org/viewtopic. ... 80#p201903

triplus wrote: ↑Wed Nov 29, 2017 7:19 pm Reference:

https://forum.freecadweb.org/viewtopic. ... 80#p201903

Thanks for testing that - will check that again.

The following same sketch is tested on 2 AppImages, 1 ok to create ArchWall, 1 failed (sometime 1 git nothing, sometime a few wall out of all edges).

The sketch had been ok to create Arch Wall for a nos of git, suddenly on recent git, I try to create a copy of wall again I found it become not successful.


p.s.
As the problem is more related to this thread, i try to continue here.



Broken on Recent git - FreeCAD-0.17.git201711241625.glibc-x86_64.AppImage
.

OK on Earlier git - FreeCAD-0.17.git201709161157.glibc2.17-x86_64.AppImage
.

I can confirm the Arch Wall command won't create the expected result on your sketch. When using FreeCAD 0.17 Daily. But if i try to delete something in your Sketch i get pop-ups saying something about issues with constraints. Therefore i assumed this sketch is also borked in some way. A created a new sketch and "traced" the 2D geometry in your sketch "by hand". This time Arch Wall command created the expected result:
Therefore my advice would be create a new file and redo the sketch. Try Arch Wall command on that new sketch after.

triplus wrote: ↑Fri Dec 01, 2017 4:41 pm I can confirm the Arch Wall command won't create the expected result on your sketch. When using FreeCAD 0.17 Daily. But if i try to delete something in your Sketch i get pop-ups saying something about issues with constraints. Therefore i assumed this sketch is also borked in some way. A created a new sketch and "traced" the 2D geometry in your sketch "by hand". This time Arch Wall command created the expected result:

Wall.png

Therefore my advice would be create a new file and redo the sketch. Try Arch Wall command on that new sketch after.

This is the problem - w/o knowing if and what may be the problem. Chrisb once has some comment on my using of sketch constraints but find it in order later https://forum.freecadweb.org/viewtopic.php?f=22&t=25071

I am aware of the pop up, though i suspect it is inherent mechanism of sketcher - deleting elements leaving some constraints to remaining relevant edges / points and 'duplicating' - wild-guessing, i have no knowledge to dig it further.


I am experimenting using sketches, linked each to the other by expression, to draw layout of wall and build on top of it. Redrawing still needs constraints I put it probably and defeat the purpose ....

Anyway, if a git version which is stable and always build walls successfully, is hopefully available, I may stick to it.

paullee wrote: ↑Fri Dec 01, 2017 7:02 pm I am aware of the pop up, though i suspect it is inherent mechanism of sketcher - deleting elements leaving some constraints to remaining relevant edges / points and 'duplicating' - wild-guessing, i have no knowledge to dig it further.

Could be there is a bug involved (or not). As this is the first time i experienced this particular pop-up i have no clue on what i would need to do to produce one. If you ever figure that please provide a step-by-step instructions on how to do it.

Anyway, if a git version which is stable and always build walls successfully, is hopefully available, I may stick to it.

You can stick with any version of AppImage to achieve that. As each one contains FreeCAD code base, important libraries like OCC... The same version therefore in general will/should always produce the same results.

triplus wrote: ↑Sat Dec 02, 2017 12:52 am

paullee wrote: ↑Fri Dec 01, 2017 7:02 pm I am aware of the pop up, though i suspect it is inherent mechanism of sketcher - deleting elements leaving some constraints to remaining relevant edges / points and 'duplicating' - wild-guessing, i have no knowledge to dig it further.

Could be there is a bug involved (or not). As this is the first time i experienced this particular pop-up i have no clue on what i would need to do to produce one. If you ever figure that please provide a step-by-step instructions on how to do it.

Anyway, if a git version which is stable and always build walls successfully, is hopefully available, I may stick to it.

You can stick with any version of AppImage to achieve that. As each one contains FreeCAD code base, important libraries like OCC... The same version therefore in general will/should always produce the same results.

Thanks again taking the time, I will see if I can single out the pop-up errors and find other examples of sketch failing to build Arch Wall and hope it helps.