: One problem w/ bamboo is its breaking point isn't so high as one would
: believe, unless you pick large diameter, not so economical stringers.
: Another problem is its diameter changes from one end to another, and those
: ends ain't perfectly round, which makes assembly difficult.
: It's not imposible to use, but far from a first choice.
: PVC lacks resilience or would be too heavy.
: Carbon fiber can do he job, but my 1st choices would be aluminium (choosing
: the wall thickness according to the desired use, for sea expeditions 1.5mm
: is safer than the regular Feathercraft 1.2mm) or wood (ash the stronger
: choice for seafaring, or pine, fir, spruce, beech).
: Depends on the lenght of the yak, too.

On kite frames cabon fiber becomes very brittle at low temperatures. But it is very strong for the weight.

I'd build a Walrus again using spruce of fir. I used WRC on my Walrus and wish I'd used something more substancial.

Roger