Multiple “heads,” like different colors in a regular printer.

One material was the “working” material, the other was a special material that reinforced the structure while the printing was taking place, and then was dissolved out of the primary material later. This allowed construction of very delicate and complicated structures. I played with a sample crescent wrench. Adjustable. It was molded in one pass, and it functions. Same for a screw-cap bottle, a set of working meshed gears, and other things.

I don’t know what would be required to do widely varied material combinations like metal or plastic, but I have confidence in the creativity of those working on these things.

For example, an automobile’s intricate sub-assemblies are made up of many different metal alloys, as well as plastics, rubber, glass, fabrics, and so on. I can see replicators making solid units like wheels, gears and shafts, but what about transmissions, or brake systems?

As for microprocessors, that should not be that hard. Chips have been made mass-produced by photo-reproduction 2-d printing techniques for years now. I remember in Silicon Valley our company’s chips’ circuits drawn by draftsmen on huge sheets of paper and then being photographed and scanned to produce the master templates for mass production of individual chips.

Essentially, each layer of a chip “sandwich” was a microfiche of a huge hand-drawn circuit.

3D printers are becoming better every day. Those that work in plastics are affordable, those that can work metals, not so much. Yet. There are printers that can make things out of titanium. There are printers that can make things out of candy.

Of course, there are resolution issues. It’s going to be a long time before something can “print” a working microprocessor. Then again, maybe not.

I believe that units of currency will eventually be energy. If there were a replicator, you would be charged for the units of energy required to create your matter.

If energy happens to be plentiful and cheap to go along with the replicator, the economy would probably be rich and affluent, so the availability of energy would be the key to solving the worlds problems.

Our “current system” is constantly introducing changes and innovations which wreak havoc on our lives, both economic and social. Granted, many of the negative consequences are temporary, and work out for the best in the long run, but to many of those who live in the transitional period, it’s massive disruption and chaos, and sometimes real tragedy.

If the population is expected to endure the consequences of revolutionary change, then perhaps those in the leadership class might benefit from it as well.

The real question is, can we predict the consequences of change, can we manage them, mitigate the worst effects and exploit the good ones? Should we even try? Our success at prediction is even worse than our capacity for adjustment.

Free food. How about free energy.

While it would be great there would be serious economic consequences. If one popped up we might not be able to adjust quickly enough to avoid the disruptions to our current system.

Not really sure what might happen.