First, I'm not sure where to post this, I think the wiki or info, but I can't find the new post button there.
After buying a cheap Chinese knock off the Revolution Power Blast 2-4, and having the middle spar break immediately, I went to the dollar store and found what is probably a SUPERIOR replacement spar.
I live in Japan so bamboo is always easy to get, but there are also hollow steel, plastic encapsulated garden stakes available for up to 210 cm for $1.00, they're stiff, not too heavy and uber cheap.
I decided to measure and make a comparison chart of carbon fiber (Cheap Chinese), bamboo cane, and garden stakes. I hope this is useful to other DIY types and anyone looking for reasonably priced alternatives.
Material Length Diameter Weight Weight /cm Density
Carbon Fiber 97.5 cm 9 mm 62 grams 0.64 g / cm 0.71 g / cm ³
Middle with two
Carbon Fiber 95 cm 9 mm 41.5 grams 0.44 g / cm 0.49 g / cm ³
with one Plastic
Bamboo Cane 60 cm 5 mm 13 grams 0.22 g / cm 0.43 g / cm ³
( whole, hollow
and circular ) 149.5 cm 9 mm 101.5 grams 0.68 g / cm 0.75 g / cm ³
149.3 cm 9 mm 86.5 grams 0.58 g / cm 0.64 g / cm ³
above two 149.4 cm 9 mm 94 grams 0.63 g / cm 0.7 g / cm ³
Hollow Steel 120 cm 10 mm 102.5 grams 0.85 g / cm 0.85 g / cm ³
Plastic 210 cm 15 mm 275 grams 1.31 g / cm 0.87 g / cm ³