I need to make a pan flute for my physics class, I've already made one but decided that I will be remaking it because it didn't turn out too good. I took 8 straws, got my wavelengths from here: http://www.phy.mtu.edu/~suits/notefreqs.html and divided them by 4 to get the length I need to cut the straws (I started from C5), then I covered the button with plasticine and taped them together. Now my problem is, I can blow and get the notes however it doesn't make any sound. (if that makes any sense). I figured the straws I used were too thin in diameter so I asked my mom to get bigger straws if she can find any. (such as milkshake straws or straws from McDonalds). Was that my problem? Or am I doing something wrong? People in my class got their flutes to sound really nice so I asked my teacher to do it on monday, even though I'll get some marks deducted.