Hi peter (is this correct or is it Peter?),
Here is a scene file:
https://www.amazon.com/clouddrive/share/2hfYB03aBMNXbGuqKZSFO28HHlFKN0mhO2eyfjoK4CN
The link above includes as well a short screen-capture of how to prepare the obj file in this case. I have reduced the segments of the bubbles, but adjust them as you like.
The shape is here a simple cube, and I have used MoGraph to produce the bubbles. Since the Volume option takes the axis of the clones, clones can stick out. With the MoGraph select, you can select those and use the Hide Selection function. If you miss one, select one polygon and Select-Connected, then delete.
For other shapes, perhaps check out the Volume method; it seems perfect for this “Material”.
Please let me know if you have any questions. I’m happy to look into it.
All the best
P.S.: the Tutorial forum is only for direct questions about a specific tutorial. If there is a question, please open a new question only via the help button. Thanks for considering.