What might prevent metal “blowing” and other forms of shaping from working if gravity was not a factor? Let’s handwave-ignore the extremes of temperature as it relates to techniques and the present primitive space habitats and craft.
Is it possible to suspend a pool of molten metal, with a tube inside, spin while adding a gas to shape a container, and form more complex shapes through additional heat cycles in a repeatable process?
You can work glass and plastic the way you can because at a certain temperature range their plasticity and viscosity are conducive to working them in that manner.
Iron has plasticity at a temperature, but lacks the viscosity until it gets too hot to have the plasticity needed. If you had a molten blob of iron in space and tried to inflate it, the material would get a hole blown in the side instead of inflating and stretching out because the working properties aren’t right.
What if the substance was only one part iron?
That would no longer be iron, then. It would be an alloy. Steel is the most common example of an iron alloy and it exhibits different properties based on the ratio of carbon and other elements.
An alloy would have to have the working properties needed, but all “metals” have the same problem of viscosity and plasticity not overlapping.