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The Young's Modulus is a property of the carbon fibre composite itself, not the specific tube. Each material has a Young's Modulus. It's just a measure of how stiff that material is.
"Tensile strength" is the most useful stat to pay attention to.
Ndeipi-
There are a couple of mistakes on that table:
1) Young's modulus unit should be GPa. Figures given for Al and Ti64 look about correct. For woven carbon it will be between 50-110 GPa. UD will be 150-300 GPa depending on the fibre.
2) Unit for strength should be in MPa. N/m^2 is valid for strength, but the figures given are not in N/m^2, they're in MPa. There's no yield strength for carbon as it doesn't yield and draw like a metal.
3) Tensile strength (UTS) figures given there for carbon are not correct. For woven carbon you'd expect to see 600 MPa for the lowest strength fibres up to about 1600 MPa for the strongest fibres. The range for UD will be 1600 MPa up to about 3700 MPa depending on the fibre and resin.
4) Density figures are not correct there. In kg/m^3 it would be 2700 for Al, 4400 for Ti64, and 1800 for carbon. Carbon is significantly lower density than common metals.
Jonny69
But I'm talking rods, not poles. And as you can see from the tent, stiffness has to balanced with bendiness. The pockets hold the poles in compression. Even 1mm rods would probably hold up the tent fabric, especially if I copy the tent with lighter fabric. Not sure what would happen if it's windy though.
I think part of the reason why the original poles for my tent are so wide is to reduce warranty claims when people break them with clumsy handling and packing. It's a similar story with many products - they have to be overengineered to keep the return rate low. But if you make something yourself you rather expect it to break (well, I do) so you just mend it and carry on. I tried to be clever by checking the numbers for the Young's modulus at easycomposites but they seem to be identical for every product. Obviously I have no idea what they mean, so I'll just pretend they don't matter.
The rack is a different thing. I have no idea about it really. It's 100% experimental. Whatever I make will have to be tested to destruction by using it for supermarket shopping well before I decide the final spec.