Yeah, a few years ago they needed a wrench on the ISS, so the engineers on Earth designed one and sent the files to the station, where they 3d printed it.
You can download the STL file for that wrench yourself and print one of your own, It’s a cool design - it prints in one piece, with fully working ratchet and everything. I printed one a couple of years ago.
Even more exciting is the ability to 3d print aatellites in orbit. Send up a small box containing a printer and the raw material, and it can spin out large antennas or other structures needed for large satellites, deep space probes or habitats.
I can imagine mining titanium powder on the moon (there’s lots of titanium in the regolith over wide swaths of the lunar surface). Send the stuff into lunar or earth orbit with either an electromagnetic rail system or a steam powered nuclear transfer vehicle, using lunar sourced water.
Once the powder arrives at the manufacturing station in orbit, it is laser sintered into titanium components of all sorts, which are then incorporated into new aatellites.
At some point, we may be able to make satellites by shipping only core pieces (electronics, motors, etc), and attaching it to structures built autonomously in orbit. I can imagine private company flying a large 3d printing facility in orbit, then offering manufactured parts like trusses and frames and antennas and such. Send up the files for all the printable parts you need for your satellite, then when you send up the core pieces, all the heavy parts are waiting in orbit.
The tech for this already exists - it’s just a matter of engineering it for space use and putting it all together. Titanium 3d printers can be had for as little as $25,000. Energy to power it is unlimited in orbit - especially if you can bootstrap construction of solar panels to power it.
Solar power sarellites are infeasable if launched from Earth, but if we could manufacture titanium trusses and solar panels in space from cheaply sourced lunar materials, it’s a whole new ball game.