Update 26.03:

I just added another version for the SpinLock that includes place for 0.8mm magnets. Print this version with supports - Enable detect thin walls if you want to print it smaller.

Please Read - Important Update:

After a gazzillion tests I see that the precise alignment depends on factors like your printer, settings, filament and more - Mine was printed on a P1S but some folks showed me that it did not align well for them - This is why I added 2 additional egg types that don't use a threaded mechanism so you can close them aligned and scale them up/down.

Bottom line: I advise to use the SpinLock version.

End of Update

I wanted to add some twists to the classic Easter eggs we see every year, and this is the first one—the Easter Brain Egg! I did my best to fine-tune the tolerance so that both halves of the brain align correctly. Please mind if you scale the threaded version up or down, it will probably affect the alignment! Your printer settings and PLA type could also have an impact due to different traction on the thread.

One has a small spin and snaps in and the other one is a simple box-like style. With that being said at 100% it should align well for the threaded version.

You should use some supports for the lower part as there are some tight overhangs, The top needs some supports in the center and the spinlock version for the internal edges.