Bridging supports.

[lozza50 0]

I am trying to print a "U" on its side, without supports. If i try bridging how is the support / pylon at the open end of "U" constructed? 

[geert_2 558]

You should be able to see this in the layer-view in Cura.

 

But you always have the option to design your own custom supports in CAD, and switch off automatically generated supports. Then you have full freedom, and you can design-in features to make removal of the supports easier, or to increase stability, or whatever you want.

 

See the pink and orange supports here, which extend from the model so I can grab them with pliers. This is a very small model, too small to get in with a knife and cut the supports loose. I also provided an additional baseplate to make the support more stable, so it is not knocked over due to its long overhang.

 

Same in red-cyan 3D, which gives better depth-perception: