Multipiece printed gnome mold.
Designed and printed shells for a silicone lined mold to cast concrete gnomes and possibly turn into a roto mold or slip casting in the future. 
Sadly I fell asleep while waiting to switch the filament roll and caused a failed print. 
Oh well 
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Awesome timing with this project! I was talking with @Thad about my wanting to make some slip cast molds yesterday. I believe @devin did a class some time ago on multipart slip cast molds. I certainly wouldn’t mind collaborating and/or working concurrently if that’s something you’re interested in!
I don’t have much experience with silicone molds, but I do have quite a history with slip casting. I have gotten some requests from local makers for help with making silicone molds, so I know there are others interested!
Either way, do post updates on your progress! Super fun stuff!
I definitely have a vision for the slip cast portion. I don’t know how well it will go since I am still learning to design the shells in blender. It took me probably 5 or six attempts over a couple months just to figure out how to design the printed shell and not use a gallon and a half of silicone. I probably should have started with a symmetrical model, but taking the easy road doesn’t always get you where you want to go. My thoughts for the slip cast are to create a dome that fits in the space the gnome goes with a void and fill the void with silicone. That way I can slide the dome out then the inner silicone.
I have some software options that could help simplify the process. Unfortunately, they’re not free… but they could be illustrative of what approaches to take. I have licenses for both, so we can investigate.
Rhino 3D has a nice Ribbon Offset feature for making mold seams on complex shapes.
Luban3D has a Cocoon feature and does cuts and keying for multipart molds. At its heart, Cocoon is really just a boolean difference from a containing shape and so it’s reproducible by other methods that could result is a smaller shell. However, the cut and keying is nice a speedy. As an added benefit, I do know the developer and he’s quite helpful with making modifications to the software or explaining how the software may already do what you want.
This vintage tree mold is an example on how to conserve material and reduce weight for a shape similar to you Gnome.
Those sound awesome. I will have to look into them.
I know my laptop can’t handle most autocad programs. It barely handles blender. A friend is putting together a desktop that can handle it for me and in return I am casting them an aluminum gnome keychain trinket. No I am not completely obsessed with gnomes. 
Just currently obsessed with them.
Tinkercad and Onshape are browser based options that should be able to be run on just about any laptop that isn’t a total #potato. You can check that the browser on your machine is up to snuff using this browser compatibility check!
I can’t remember if I tried tinkercad. Is that one related to fusion 360? I know fusion and the free one attached to fusion are too much for mine. Mine is supposed to be a “gaming PC”. But it can’t handle remeshing in blender.
Remeshing can be rough. No, tinkercad and onshape are unrelated to fusion. To be honest though I’m not sure how well they handle meshes and mesh booleans… we can play around and find out!
Tinkercad is the browser based free autocad my laptop can’t handle. It’s owned by Autodesk which owns fusion 360
Oh, well, yes then… I meant programmatically related, but your point’s taken about them being organizationally related! Did you try the browser compatability check for onshape?
Not yet
Got a friend putting together a desktop that can handle autocad. Gonna just wait for that.
