Is there a mod that allows me too...

[vetrox]

Weld parts together After they have left the VAB?

Edit: I'm not even sure if it's possible

[SpaceGremlin]

Kerbal Attachment System has this to a very limited degree. You can add/remove many small parts from ships while on EVA. It even has struts for strengthening docked ships together.

[vetrox]

Kerbal Attachment System has this to a very limited degree. You can add/remove many small parts from ships while on EVA. It even has struts for strengthening docked ships together.

But no way for me to permanently attach 2 fuel tanks for example. I just had an idea that I could construct a small rocket using things like KAS and robotic arms and some makeshift cranes. But obviously without any way to permanently attach things I would be limited to docking ports and therefore smaller ships