Mimimum width, length, and thickness of objects that can be 3D printed successfully?

[curious aardvark]

is that file in inches or millimetres ?

is it supposed to be 2.69x1.56x0.12 mm ?

In which case - it's way too small to print.

Look at it this way it would be 0.12 mm thick. You couldn't get it off the bed without breaking it to start with.

For that you need a decent sla machne.

Actually it should at least make the square and all I get is a horseshoe shape.
So how did yu make the stl ? I reckon there's problems with it.

Though s3d does say it's 100% manifold.
weird