QUOTE(Stephan @ Sep 25 2011, 11:40 AM)

Hello man! I've been trying to make one too, but still at experimenting stage... as for hole placement, I got some pictures of xiaos, measured them and counted the percentage (first hole 30 percents from top, second... not for real just example) and now I'm trying to figure out the inside diameter... Made one 8 hole about 30 inches (96 centimeters) long with inside about 19 milimeters.. sound is too low (deep? not really a musician... and maybe the holes are to far from the blowhole), holes kinda hard to reach... and one about 20 inches (69 cm) long, inside diameter about 16 mm with 6 holes... sounds more like xiao than the thicker one...
so back to your question - try to get some info on inside diameter.. not much help I guess, sorry...
By the way - Does anyone here knows something about this? I'd love some advice too...
Hi - I'm probably not much farther ahead than you when it comes to making Xiao. I've had some success making other flutes and have been at it for about two years. It helps that I am a musician, for the testing of playability and other features. I've made my eleventh Xiao just recently and have sold one and given away four. I make them in G and F, based on a Xiao I bought a couple of years ago. Diameter will affect pitch and the wider ones are the lower pitch. I took the measurements off my example, unlike the calculator I had for my NAF's and Shakuhachi's. I matched drill sizes to the holes on my model and used tuning holes to cut off the end of the flutes sounding tube length. I went from node to node for strength and at the blowing edge end used the node as part of the width for the blade. I could tune the holes somewhat by enlarging to go sharper in pitch. I've also used the method you mentioned calculating the ratio for different lengths from a model or picture and scaling up. I made several out of Black Bamboo and have a jpg of one here. I also find the Xiao the hardest flute to play that I've made or own, with the execption of the Ney.