I’ve been making flutes and whistles lately. Well, 3D printing them. I feel like that counts as making, but others may disagree. In any case, I have a lot of whistle and flute prototypes around now.
I’ve found a couple interesting things:
The smoothness of the bore is super important
A friend had me print a flute in “silk PLA”, which is PLA with Polyurethane mixed in. Polyurethane is the same stuff they use to finish furniture or “wax” wood floors: it’s shiny. The silk PLA flute plays noticeably better than any other flute I’ve printed.
I printed a second silk PLA flute, and it also plays better than anything else I’ve printed. Not quite as good as the first silk PLA flute, but very good.
I’ve come up with a few possible explanations:
- The shiny surface, at a microscopic level, better mimics a smooth bore like a metal flute
- The silk PLA, which contracts when it cools, is stringing less inside the bore, making the bore smonother
- The higher temperature I’m printing with makes the perimeter melt together better, making the bore smoother
You’ll notice what all three of these have in common…
Making a smoother bore
So I think my next step needs to be focusing on making a smoother bore. I could print everything in silk PLA from now on, and I might do that, but maybe there are other things I can do to get a smooth bore.
One idea somebody at the beer co-op (LOL) pitched at me is printing the flute horizontally. Right now I print vertically, so the inner bore is essentially a bunch of stacked concentric rings. But what if I printed vertically? I could then make each line of material run the entire length of the flute. It may still be rough, but roughness in this direction may not matter.
The only problem is, how do you get the round inner bore to print without supports? Simple: you make it a lozenge shape!
My “musical instrument design” book assures me that the shape of the bore has almost no bearing on the instrument’s playability. Assuming this is true, I just need a flute design with a square rotated 45° instead of a circle. Almost all printers can easily print a 45° overhang.
Then you just need a way to prin the outside without supports making the surface all gross… why not abandon circles completely, and print the flute as an octagon, for instance?
It’s a wild idea, and it would look nuts, but necessity is the mother of invention, and I can get a good-playing octagonal flute for $7.50 in materials, people might be willing to look past the shape.