AsterAnts

>
> But the "machine tools" needed to put raw asteroidal material into
> usable forms will likely have significant mass. So using
> extraterrestrial materials could significantly lower the cost of
> construction and operations in space if the tools are there, which
> would suggest a large operation, not on a few tons.
>
> Yes, it is an inevitability of this logic that use of space resources
> only makes sense above a certain scale of operations.

I don't see that. This can make sense in the very small scale too.
Many asteroids contain metals that can be separated by heating
alone. If you can capture an asteroid using small reusable
radio controlled ion drive probes it is a lot cheaper to get mass
that way than launching from earth.

I mean the ISS cost how many billion? How many DS1 class spacecraft
would you need to get a hundred tonnes? Not many; and most of
the cost of DS1 was the design.