[Help!] G-Code generation not reliable

[lagarkane 0]

Hi Guys!

I've am struggling with a print, and I really don't know what to do anymore!

I modeled an object using FreeCAD, and converted it to a STL file. The STL file is flawless and perfectly represent my shape, but once I feed it to Cura (or any other slicing software for that matter), The g-code separates some parts of my model, making the print easily breakable. here are some pictures to illustrate my issue:

As you can see, the helix is not well connected to the walls of my print, nor to the center support rod.

At first I thought this was caused by the thinness of my walls (0.5mm) in the STL itself. but I increased it to more than 4mm and still have the same issue! I also tought it could come from the fact that the helixes inside my tube would not be considered as connected to the tube, so I made the two overlap: didn't change anything. I tried increasing the wall thickness in cura directly also, with no success. I tried reducing the layer height, the nozzle diameter also.

I am sure I'm not the only one doing this kind of prints.. so does anyone know why it does this? and how to solve the problem?

I'm looking forward to your answers!

[gr5 2,173]

It's a cad issue. You could fix this with meshlab.

Or maybe there is a way in freecad to merge all overlapping objects into one object?

I know DSM. In DSM I select everything and there is a button to merge.

[robinmdh 100]

it does indeed look like a CAD issue, use a boolean operation to merge all objects into one...

Cura sees the walls of your 2 objects separately and since they then intersect weird stuff happens in determining what is inside the print and what is outside.

Interesting to see that it's a mixing nozzle, what are you mixing?

we have someone here that prints those as well.