ZBrushCentral

How to trim a cube model to the shape of an STL model?

ZBrushCore Usage Questions
#1

New to 3D modeling and Zbrush, appreciate any help y’all can throw at me. I don’t know all the lingo, but hopefully my screengrabs will help explain what I’m facing. Context here is I’m playing with ZBrush to ultimately design relief carvings from my CNC Router (using MeshCam in the middle to create toolpaths).

I have an imported STL model of a heraldry belt - it really is just the top of the shell, it doesn’t have a backside. I added a cube subtool and squashed it, positioning the belt just inside it, so it looks like a relief carving on a piece of wood.

STL%20Model%20Front%20and%20Back
Belt%20and%20Squashed%20Cube

Additional design will be sculpted in the middle of the belt.
I don’t really want this bigger squashed cube background. I want the outer limits of the model to be in the outer shape of the belt. In Photoshop, I could Magic Wand the belt and use that to cut the cube.

How can I accomplish this in Zbrush?

  • Is there a good way to cut the shape?
  • OR is there a better solution working with STLs to create a backside that I could then play with? I tinkered a bit with ZModeler, and that seemed like a good way to lose my mind.

If it helps, I zipped up the ZPR and can be snagged from my Google Drive:
Heraldry Belt Test 1.ZPR.zip

#2

I too am using zbrushcore for create models for use on the CNC.

I use Vectric Vcarve Desktop 10.5. That has a clipping function which makes use of vectors to select the parts of a 3D model that you want to eliminate. It also has a way to adjust the base height of the model so you could basically cut off the base. Not sure if you have access to that software or if Meshcam has this functionality.

In Zbrushcore you could probably use masking to split the merged model to eliminate the box parts you don’t want. If you have a vector of the outline of your STL you could import that into Zbrushcore and use the Vector Shapes Zplugin to create a base that has the same shape as the STL model.

The Meshmixer free software has a number of tools that might let you adjust your STL before bringing it into ZBrushcore.

Good luck with it.