Hello,
Could I ask those in the know, what is the minimum diameter of plastic rod you could turn a conical bore Dflute out of? The skinniest flute I have here is 2.6 cm external diameter at the head increasing slightly (very slightly) over the slide. That’s a 1905 ish cocus “Improved London”. Do flutes come skinnier than this? How about a slideless plastic one?
Many thanks
Julia C
Julia, I’d aim to get 29mm - 30mm at least where the embouchure is, you could make a raiser lip plate to save money on material?
the minimum diameter is 26.5mm but I like the deeper chimney for woody tone, and it’s always about me, ALWAYS!! 
I think that material would work like casting resin, which is a bit elastic and soft, and not brittle enough for a crisp tone? but then again PVC and Delrin flutes sound great.
maybe you could find the hardness level, and compare to the other plastics?
do you have a lathe?
good luck, I really like how you take on projects, thats great!
eilam.
The fattest part of a flute is usually the bottom end of the barrel.
The smallest example I have is 28mm at this point (excluding tip ring).
Thanks for the measurement, ectophonic. A bit like my Cocus.
Eilam, I have a dream. Not a very tasteful dream (see my post on “can you turn a flute out of these plastics” below) but a kind of multicoloured pearlescent dream with tortoiseshell rings. I’ve tried using a lathe and made some tool handles but the speed and the noise and the dust and the terrifying machinery to get dragged into by your long hair were not my idea of a good time, so I’ll be looking for a flutemaker with no aesthetic qualms about blue spangles to help me out with this project.
So far the only supplier I found offers this stuff in sheets 1mx1mx2.5cm, not quite thick enough, although one slab of it would make 33+ flutes of dubious desirability. Oh and the minimum order is $1500 
As Dolly Parton said, It costs a lot of money to keep a person looking this cheap.
the smallest i have is a blackwood Doyle at ~27mm at the embouchure & ~29mm at the head-body joint. it seems like a pretty dainty flute to me. my Tipple pvc flute has a wall thickness of 3.2mm. on top of a 19mm inside head diameter that makes ~25.5mm. Doug gets great tone out of his embouchures at that thickness.
enjoy! /dan
ps- i think a faux tourquoise flute would be amazingly cool! 
Julia, why don’t you make your own rod from casting resin, it’s not very hard to make it like you want (especially with your hands and patience) cast it into a clear PVC or what ever clear pipe that polyester does not bother, then send it to a maker that works with plastics, like Jon or M&E, and have them make you a head joint, if it works good, then the rest of the flute?
OK, cast one for me too 
please.
This link might help, supplier I used to use.
http://www.amariplastics.com/
They will do small orders as I recall.
Rob