Using Concrete to build space ships...

>> > I imagine that vacuum would play
>> >havoc with the whole mess anyway, even if water were easily available.
>> >
>>
>>I dont see why. Vacuum isolates, yes but does it hinder the binding
>>process of concrete?
>>You need temperatures of more than the freezing point at 0 grade
>>Celsius or better more than 15 grade and you could warm the concrete
>>molds with concentrators and ordinary exposure to sunshine just to the
>>right temperature.
>>
>Actually, I hadn't thought about the temperature thing... But keeping the
>hardening concrete at a uniform temperature will prove difficult at best.
>For instance, sunside or concentrator side may be up to temp, but the shaded
>sides will be a few degrees above absolute zero. I am sure it's possible,
>but... There's that Murphy thig again and additional expenses.

I did not see that as so threatening since we could place as many
concentrators as needed around the mold and have a broad temperature
spectrum left to play with.

>
>What I had actually thought about as far as difficulty in the vacuum was the
>boiling off of the water with the absence of pressure. I would imagine that
>it would cold boil the concrete.

I think less pressure would make the process simpler. What do you mean
with cold boiling? Is it actually possible to cold boil something in
lower temperatures without high pressure?

Frank