How to create a multi-part mold of large object?

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I’m trying experimenting with making plaster and concrete objects by creating molds with my 3d printer. I’m confortable making small objects who’s mold fits entirely on the 8" 3d print bed. However I am experimenting with new objects of very untraditional and sinuous shapes several feet across and need to create multi-part molds that can be bolted together for a single pour before getting broken off. I have seen this done before using Rhino (see screenshots) and have tried many tools listed in previous threads to no avail.

Ideally, I’m looking for a tool or workflow that would simply let me offset an object by the thickness I want (0.25") to create the mold, while leaving a void that is the shape of the original object?

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You’ll want to use the V8 Beta with the ShrinkWrap tool, and use a positive offset value to get your outer mold surface (not to be confused with OML lol). Then you can chop that up with traditional tools to fit your printer. Also note that you can ShrinkWrap, then QuadRemesh and convert to SubD if you want to edit it. Lots of great info from Kyle here:

I personally used this workflow on some 3d printing I did recently and found it’s pretty great.