Years ago my daughter had to make an instrument and write a report for a science class. She used PVC pipe, and the 12th root of two. Her PVC-laphone did allow the playing of simple tunes. Learning did occur.
This thing has turned out to be a nightmare. Using the online calculators which work off of a sample that has been properly tuned. None of the suggested measurements are anywhere near close enough. I am using 8 tones per octave. I bought one of those little tuners to read my notes with. Taking me forever to make any headway.
I just tried the calcualtion with 7 tones per octave and it seems to be getting closer.
Now I have it, I was getting confused by the shrps and the flats.