Drawing a circle normal to a sketched line

[Chaot]

Hi everyone,

I havea problem finding a feature in FreeCAD up to the point where I'm starting to doubt that it exists. I'm trying to design a bicycle frame to my liking. My method of approach is sketching the frame in the sketcher, and after that sweeping a circle along the sketched lines to form the tubes. As an example I show my intent with the headtube below. In order for this to wirk the plane of the circle needs to be normal to the tube to be swept.

My problem now it that I do not find an option to have the circles automatically normal to their respective tube. This means that when I change a parameter in my sketch I have to go and rotate all the circles by hand, which is a mayor headache. Does anybody know the correct way to create such a link?

Thank you,
Chaot

[jmaustpc]

Hi and welcome to the FreeCAD forums.

Firstly could you please always paste your Help menu...about FreeCAD data so we know what you are talking about...this data is nearly always at the very least useful and often vital.

How to do this and other commonly asked basic stuff is explained in the first "sticky" topic at the top of this Help forum, labelled
"IMPORTANT: Please read first before asking for help".

[Chaot]

Hi. Sorry, I did read that, and copied it before starting my post, but then forgot to paste it in the process of writing.
I have the version that comes standard with Ubuntu 14.04:
OS: Ubuntu 14.04.1 LTS
Platform: 64-bit
Version: 0.14.2935 (Git)
Branch: master
Hash: eab159b6ee675012bf79de838c206a311e911d85
Python version: 2.7.6
Qt version: 4.8.6
Coin version: 4.0.0a
SoQt version: 1.6.0a
OCC version: 6.7.0

[NormandC]

Hello Chaot,

Sorry, I did read that

OS: Ubuntu 14.04.1 LTS
Platform: 64-bit
Version: 0.14.2935 (Git)

But did you read the section right below "Please provide your FreeCAD info"? I'm talking about the one titled "Are you sure your FreeCAD version is current?"

You will realize that in your case, the answer to that question is a definitive no.

My problem now it that I do not find an option to have the circles automatically normal to their respective tube. This means that when I change a parameter in my sketch I have to go and rotate all the circles by hand, which is a mayor headache. Does anybody know the correct way to create such a link?

Unfortunately, AFAIK there is currently no way to do that. FreeCAD is still missing a lot of functionality, in the parametrics department.

[Chaot]

Unfortunately, AFAIK there is currently no way to do that. FreeCAD is still missing a lot of functionality, in the parametrics department.

Ok, thanks for your answer.

[NormandC]

A forum user has created a macro called Macro WorkFeatures to facilitate creation of planes and other working geometry. I wonder if the created elements are parametric, I have yet to try it.

I think it may be possible to write a macro that creates a sketch normal to an edge, and keep it linked to the edge. But my python knowledge is too limited to write such a macro. I would definitely find it useful.

That being said, please update your version of FreeCAD, you will get a much more functional version than that old, buggy package from Ubuntu 14.04's repository.

[rockn]

I think there is a workaround.
In the Arch workbench there is a tool called Frame. This tool take a profile (in you case a circle) and a path (can be a line in a sketch) and make a sweep.
The frame objet have the Align property that make the profile is automatically normal to the line. It have some problem with rectangular profile when the line is not in a global axes, but with circle you don't worry about that.

You need a up-to date FreeCAd version.

[bejant]

Hi Chaot,

I have the version that comes standard with Ubuntu 14.04:
OS: Ubuntu 14.04.1 LTS
Platform: 64-bit
Version: 0.14.2935 (Git)

please update your version of FreeCAD, you will get a much more functional version than that old, buggy package from Ubuntu 14.04's repository.

You can get the 0.15 development version here:
http://freecadweb.org/wiki/index.php?ti ... A_packages

Or the 0.14 release here:
https://launchpad.net/~freecad-maintain ... cad-stable

You'll be much better off using the 0.15 version though; it has a lot more functionality than 0.14 which itself is getting old now...

[sgrogan]

@rockn

That is awesome. Thanks for the tip. How long has this existed?

OS: Windows 7
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.15.4537 (Git)
Branch: master
Hash: 79173e37cd0886e197129bf06bfbee01890480b3
Python version: 2.7.8
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.7.1

[NormandC]

I think there is a workaround.

I do not call that a workaround. I call that a solution. Or maybe a life saver.

It's awesome. You don't even need to align your profile to the end of the path. Just make all your profiles on the XY plane, the Arch Frame tool does the rest.

I was not even aware of this feature. I should definitely use the Arch workbench more!!!

And I'm certain another forum member designing bike frames will be delighted to know of this (Cat Oregon).

Thanks for the tip rockn! Today you're the , not me.