Comments on Next Big Future: Creating strong macroscale Carbon nanotube materia...

Thanks bw. They looked about 100:1, but it's been ...

2008-07-08T07:34:00.000-07:00

Thanks bw. They looked about 100:1, but it's been a long, long time since I've used any units like these. The side effects of the schooling and practice of law, I'm afraid.

Still, it's very nice to see such progress. It's been incredibly exciting watching our progress approach the necessary tether strengths so rapidly.

They are not using the same units. Spaceward.org i...

2008-07-07T20:44:00.000-07:00

They are not using the same units. Spaceward.org is focused on GPa cc/g

Which is the first column of the CNT tech chart g/cc divided into GPa strength. GPa strength is 1.5-3.3 GPa which is listed in the paper. I have calculated the CNT Tech material to be 6-16.5 GPa cc/g. This is in between the two announcments that spaceforward is quoting. Once at 9 GPA cc/g and the other at 40 GPa cc/g.

The specific strength CNT tech is using is different from units for specific strength. I believe the CNT tech units are 1/100th the wikipedia numbers.
http://en.wikipedia.org/wiki/Specific_strength

What aren't I understanding about the cnt-technolo...

2008-07-07T17:53:00.000-07:00

What aren't I understanding about the cnt-technologies slides? Their "Specific Strength" tables don't have any units. What does it mean they have a specific strength of 172.7? According to wikipedia, steel is better than that and kevlar has an ss of 2514.

I must assume I'm reading something wrong, because CNT Tech's chart says kevlar has an ss of 20. What gives? What am I missing?

Is spaceward.org using the same units of measurement as CNT Tech? They say that an optimal space elevator cable will need an ss of 80. Did CNT Tech really more than double that?