Polar Transformation Failed

[jonahugh]

Hi,
I carefully created a tiny sketch, which I have attached (cap.FCStd) and was hoping to generate a polar transformation of 115 ribs around a full circle.
I went over my sketch after it failed the first time, and added points to the centre-point of each of the four curves, then went around and deleted each curve, redrew them and did the same with the straight lines. I then deleted the points which I had added as references.
The purpose of this exercise, was to ensure that there were no hidden artifacts, and to ensure that all line segments joined properly.
I was able to create a pad using this sketch, suggesting to me that it was okay, however, when I clicked on Polar Transformation, it came up with the following error:
One transformed shape does not intersect support
Transformation failed
I would be most grateful of any help please.
Thanks and Regards,
Jonathan

[jmaustpc]

Moved to help forum.

I am on my phone, I will look at your file later when on a computer if no one else has answered in the mean time.

According to the error message you have something not intersecting.

[jmaustpc]

It's not clear what you are trying to acheive.

The Sketch in your file is empty, all the lines etc. in your file are Draft workbench objects..

A PartDesigin Polar Pattern is a patter of features of one single solid object (Body), A Draft Array is an array of separate solids that can optionally be fused into one object. These are therefore totally different things, although they are often confused.

Generally in FreeCAD and always in PartDesign WB, you model a real thing. A line is not a real thing since it has only one dimension hence can not exist in the real world.

For example if the object you have shown in your file above had been intended to be a spokes bicycle wheel then those lines would need to be cylinders not lines since a spoke has a diameter.

Since you have named some lines including "Rib", I suspect there maybe a better way to model your object.

A screen shot from your file, did you post the wrong file?

Screenshot_20210509_132347.png (110.74 KiB) Viewed 702 times

Please always add your FreeCAD version data when asking a question.

OS: Ubuntu 20.04.2 LTS (KDE/plasma)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.stable PPA
Build type: Release
Branch: unknown
Hash: 9e3b630bbfb6807e93eeffb655e6c20f218644fc
Python version: 3.8.5
Qt version: 5.12.8
Coin version: 4.0.0
OCC version: 7.5.1
Locale: English/Australia (en_AU)

[mendy]

Based on @jmaustpc's observation sketch is empty.
Here is real wild guess using two different methods in PD.
One is round ribs on outside and other is ribs on inside similar to a cog pulley.
Just wild guess with info supplied

OS: Ubuntu 20.04.2 LTS (MATE/mate)
Word size of FreeCAD: 64-bit
Version: 0.20.24825 (Git) AppImage
Build type: Release
Branch: master
Hash: ccc4151b3020969450325466e385850783795325
Python version: 3.9.2
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.1
Locale: English/United States (en_US)

[jonahugh]

Thank you all very much for your feedback.
Firstly, I should mention that I am trying to create the ribs around a PET bottle cap.
After posting about this issue, I tried a few different things, and am not really sure why, but I left it for a couple of minutes, and found that it had generated the polar array (please see the attached file.)
My concern really, is what caused Freecad to generate the error, so that I can be sure to follow a procedure which will avoid this kind of problem in future.

I am most grateful for your kind assistance.

[Bance]

Your model has only 3 occurrences in the polar pattern.

Should be 2piR/width occurrences.