Star Simpson

3D printing steel is extraordinarily expensive and you'd end up with serious mold marks without manual labor for hand finishing

and you'd have serious surface area so I'd have demolding concerns. Like a lightweight mold can be a few hundred pounds of metal

Essentially, this is so inconceivable you'd just never do it

"Cheap/few use" molds can be done in aluminum but you're still looking at qtyies significantly higher than 10 to justify mfg cost

If I understand correctly, we have to use metals because injection molding is very high pressure? What about lower-pressure mold processes?

Maybe the disadvantage is that no lower-pressure mold process can equal the surface finish of FDM?

I mean clearly vacuum forming and blow molding can be done with softer mold materials, as long as they don't melt or stick (?)

When I think about metal casting, the pressures are just the hydrostatic pressure of the metal; I wonder if something like that can work?