Hi,
The dixon flute wins hands down! I think the conical PVC flute has potential though. This was my first attempt at making a conical PVC flute. The PVC flute is a lot mellower then the Dixon flute. The advantage is that it is lighter and thinner, due to the wall thickness. It has the feel of playing a whistle due to the narrow profile.
Jay, I really think you will like the Dixon flute a lot, when it comes…
Jon - I’m sure I’ll love the Dixon - I’m just antsy and very impatient.
I’m not surprised the PVC conical sounds good. PVC really is a nice material for sound, but with a cylindrical design the upper octave is simply weaker and the finger stretch is larger.
Keep working on it. If you get it sounding the way you want, I’d bet you’d have a market.
Depending on what distance you have between centers on your lathe. Could the tapered mandrel be made longer on the large end, and use a longer piece of pvc? Then when the pvc is cool, and removed trim the small end till you reach the ID required, then trim the other end to length and the Id should be correct. With a longer mandrel and longer pieces of pvc you would not have to keep making a different mandrel till you found one that allowed for the pvc shrinkage. I would also anticipate that till an evan heat applied and evan cooling that each tube will shrink different. The longer mandrel would compensate for this.
Wow, I remember that project! 5 years ago!
Never did figure that out…
It was much easier to turn a piece of Blackwood into a flute, which I ended up doing.
What kind of PVC are you using? Electrical conduit?
Well it was a few years ago, but I was using grey electrical PVC, as I am a electrician…
I didn’t know that! No wonder you’re a careful worker, Jon. Hmm, come to think of it, maybe being an electrician doesn’t necessarily make one careful. I once had a house rewired. The electrician saw me staring at a bunch of blown fuses on the floor and said, “Well, everybody makes mistakes!” Very comforting…
That’s very cool 
. Conical flutes for the working man. Beach flutes. Rock climber flutes. Flutes that don’t set off metal detectors. Swim to the floating dock and play for the fish. Lighter than delrin. What else? Don
Flutes you can stash in the car, truck and motorcycle!
Oh, how young we were! 
Hey Jon
It works better with a polished stainless steel mandrel. You can leave it on the mandrel until completely cool and avoid shrinkage. The same mandrel can be used for baking polyclay bores (polyclay is pre-cured PVC) and even “no-fire” ceramic. I also recommend you try at least one flute made of clear acrylic Lexan tube.
Don’t forget to glue a dime to the end of the cork on that Dixon Jon…
Tom