zhivko wrote:but first I need to cut it:
1) can this be done in FreeCAD or it should be done in Inventor and than import cutted part?
This can be done in FreeCAD. I made it with the Step-version of your tube. It seems the Iges-version has problems to do so, because this versions does not define flat faces of the tube-sides.
1. Start FreeCAD and open your step-file.
2. Select the Part-Design Workbench. Have a look here about help for workbenches: http://freecadweb.org/wiki/index.php?ti ... ch_Concept
3. In the 3D-View select a flat face of your tube.
4. In the task-tab select "Create sketch"
5. Draw a small rectangle along the entire length needed to be cutted. (In case of problems with the sketcher, you may have a look into this tutorial: http://freecadweb.org/wiki/index.php?ti ... r_Tutorial
6. Close the sketch
7. In the Tasks-Tab of the Part-Design workbench select "Pocket"
8. I got the settings for Type: "Dimension" and for Length: 5 mm, which will do a cut of one side of the tube.
9. Select one flat face of the cutted tube in the 3D-View.
10. Call the macro "sheet_ufo12.py" from the macros menu. (You need to copy this python-script into a folder of your convenience. And set this folder as your macro-locoation in the FreeCAD-preferences. Menu: "Edit/Preferences" and select in the dialog "General" and the tab "Macro" )
After some calculation time, you will get a bunch of flattened Shapes. Your tube contains a feature, that can not be handled by the macro. The macro was coded with the assumption, bended portions of the to be unfolded part have only edges parallel or perpendicular to the bend-axis of this portion. This is not the case with your part. The following picture shows the problematic bended face:
So the macro returns the unfolded faces it made. Due to the not handled difficult bend feature, it could not generate a solid from the unfolded faces.
In order to get something better with the actual version of the macro, this portion of your part has to be changed into something, that can be handled by the macro.
Otherwise, select the faces, you can use and export them as Step.
This is the FreeCAD-version I used for the unfolding:
OS: Debian GNU/Linux 8.0 (jessie)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.15.4587 (Git)
Python version: 2.7.8
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17-dev