Cut complex model along plane

SketchUp 3D Printing
1

Hello everyone!
I was trying to edit a .stl file I downloaded in order to print it, but I encountered multiple problems. I am going to share all the files I’m talking about, so it will be easier for you to follow. You can find them here.

So, my file is the miner.stl one. I tried to import it in a new sketchup file with little succes: the application becomes unresponsive and after a few hours I terminated it.
Because of that I used an online converter to create a .3ds file which is miner.3ds. That way I was able to import it in the sketchup file (however this file is now 119MB! What the hell?).
However I need to cut it, as you can see in the miner_flat.skp file. I just need to remove the back of the miner that goes over the plane.

I simply can’t find a way to do so. Can anyone of you help me? It would be much appreciated!

2

I used MeshLab to import the STL and export it as a DAE file. Importing the DAE file into SketchUp and intersecting with the ground plane, gives this after trimming:

image
image472×671 66.4 KB

The SKP file is about 14.5 MB:

3

I had no trouble importing the .stl (you may need to change the import options, I’d suggest importing in meters). It imported in a matter of seconds on my old slow PC.
But once you open it up you’ll see that it has been made with lots of bits put together, so you’ll need to clean all that up to make a solid in SU.
I split this into two separate groups using a section plane.
Split%20Miner