Fixing models for STL Export - non manifold edges etc

I’m trying to fix several models for export to STL and print, to be honest i’ve losing hope and feel like the work i’ve done is now a total waste of time. The place i sent for the casting said the models are not possible to fix. They all have different issues which I cant / don’t have the knowledge to fix. I use rhino for architecture but we never print anything so this is all new issues to me.

Starting with this first one, i have divided the model in to the part that is most issue which is the head, can it be fixed or am I wasting my time here… If so how do i model this correctly so it can be printed, any help would be appreciated.

This is before i joined everything together so not the actual model exported

001_GeoRose_STL_EXP.3dm (5.2 MB)

Hello - it is a bit of a mess - the outer shell of the ‘pettles’ has a lot of nonmanifold edges - the rest seem OK so far and can probably be unioned if the outer shell petals is cleaned up - ‘Layer Pettles L1’ That object has zero thickness at the ‘top’

as well as the non-manifolds.


i remade the shapes but simplified the number… same issues… if not more
all the meshs are good before any union, most either don’t union or autodelete… takes me 1 hour to model and 3 weeks to fix to print…
how can i achieve this model? must be a way… another way

001_Head_forum upload.3dm (409.4 KB)