What's wrong with my model?

[mirko 1]

Hi,

I've just changed my workflow a bit (among other things, I now have the original heated bed for the Ultimaker Original and this is also my first print with Nylon, but that is probable not the problem here).

I've started to use FreeCAD and I'm trying to print a part that comes out somewhat "inverted" - features that should be printed are left away as if something is wrong with the model. I do not know what software or step causes this, so let me show you my files and pictures below. As you can see in the last picture, the vertical part at the rear end and the rim around the whole part have been omitted and there is a blank surface instead. I stopped the print when it became clear that something is going wrong.

The work flow is: I design in the Part Design workbench in FreeCAD, then export as .stl, input into Cura, change some settings (mainly temperature I think), then copy onto SD card.

I'm using Ubuntu 15.04 with FreeCAD 0.15 and Cura 15.04 (installed the firmware from that, too, newest version of Cura crashes on my computer).

Model in FreeCAD:

wrong.fcstd

Model in Cura:

wrong.stl

wrong.gcode

Outcome:

Mirko

Edited July 10, 2015 by Guest

[Remy 13]

Hi Mirko,

I looked at the gcode using this gcode viewer: http://gcode.ws/

If you look at file in the 3D view, you can see that the portion that connects the vertical part to the flat area didn't get sliced. I'd recommend running your part through netfabb basic repair to make sure everything's watertight, etc.

Netfabb basic: http://www.netfabb.com/downloadcenter.php?basic=1

You can repair the part under Extras>Repair part. This usually works for me.

[gr5 2,268]

Also never ever print a part without looking at it in Cura layer view. If you had done that you would have seen the problem before writing gcode to SD card. Also use the xray view in cura and it shows problems with your model in red.

[gr5 2,268]

Also if you model is good you can uncheck all the "fix horrible" checkboxes as they make a good model print badly.

[mirko 1]

Thank you very much for your answers. I really never looked at my models in layer or x-ray mode, because all the OpenSCAD models just worked.

Experimenting some more, it seems that FreeCAD creates usable STL files unless you add fillets to the model. I'll have to avoid these for now.

Mirko