Transverse Dizi-Style flute (Bb13, flush membrane) version 1.1

# Transverse Dizi-Style Headjoint (Bb13, flush membrane, thick-wall embouchure)

A 3D-printed transverse flute, converted from a fipple whistle design,

with a dizi-style sympathetic membrane hole. Bore and tuning are

carried over unchanged from a working Bb13 fipple whistle, so the pitch

should match anyone printing from the same bore.

## What this is

- Bore: 13mm ID, 2mm general wall (17mm OD)

- Embouchure (blow hole): plain round hole, 9mm, blown across

directly rather than through a fipple/whistle mechanism -- a

genuinely harder thing to voice than a fipple whistle, requiring

real embouchure control.

- Thick-wall embouchure boss: the wall locally around the

embouchure hole is built up to 3.4mm (from the general 2.0mm),

tapering smoothly out and back so the tenon/socket joint is

unaffected. This is not cosmetic -- see Status below. The extra wall

thickness gives the airstream a real "chimney" to speak against;

without it, the embouchure edge is too thin and sharp to control.

- Membrane hole (mo kong): 8mm, flush-cut, positioned ~40% of the

way from the embouchure to where the first tone hole sits -- standard

dizi convention. No printed clamp or boss (a printed membrane clip

was tried and abandoned -- see Membrane section below for why). The

membrane sits at the normal 2.0mm wall thickness; only the embouchure

region needed thickening.

- Tenon/socket joint at the tail end, mating with a body/tone-hole

section carried over from the Bb13 whistle build.

## Status: playing a full octave, clear tone

**A full octave is playable, with a clear tone and confirmed membrane

buzz.** This is a major improvement over the original thin-wall

version of this headjoint (general 2.0mm wall all the way through the

embouchure, no local thickening): that version was high, breathy, and

weak, with the octave essentially unplayable. The thick-wall embouchure

fixed this directly -- same underlying problem and same fix as was

independently found on a related fife build using the same headjoint

lineage, which is a good sign this is a real, repeatable fix for this

failure mode rather than a one-off.

Not yet independently confirmed against a tuner across the full

register -- what's confirmed so far is by ear: full octave achievable,

tone clear rather than weak/breathy, membrane producing real buzz. If

you have real dizi or transverse flute embouchure and can test/tune it

more precisely, that feedback is welcome.

## Membrane

**Don't try to clamp or mechanically retain the membrane -- glue it,

by hand, with a deliberate wrinkle.** A printed retention clip was

tried and abandoned: it's the wrong category of solution for this job.

Real dimo application isn't about even tension or a secure mechanical

seal -- it's the opposite. The traditional technique uses a glue that

stays workable while wet (traditional ejiao, peach resin, or a plain

glue stick all work), and you actively stretch and rub the membrane

with your fingers to form deliberate parallel wrinkles while the glue

sets. That wrinkling is what creates the buzzy tone -- more slack

means more buzz, not less. A rigid clip physically prevents the exact

hands-on manipulation this technique depends on.

Any thin, slightly translucent paper or plastic film that can hold a

loose drape works -- greaseproof/parchment paper, thin plastic, or

real dimo if you have it. Glue stick is a legitimate traditional

adhesive, not just a workaround -- expect to reapply every few weeks

with regular playing, which is normal maintenance for this style of

instrument, not a sign anything is wrong.

## Files

STL only. Source isn't included with this release.

## License

CC BY-NC-SA -- attribution required, non-commercial use only,

derivatives must stay open under the same terms. Fork it, change the

bore, move the membrane hole, add tone holes, whatever you want -- just

credit me, don't sell it or a derivative of it, and share your version

back under the same license.

## Background

This headjoint began life as a fipple whistle mouthpiece (Bb13) before

being converted to a true transverse embouchure and then given a

dizi-style membrane. The embouchure wall was later thickened locally

around the blow hole after real playing feedback showed the original

thin wall made the instrument nearly unplayable -- a fix carried over

from the same discovery on a related fife build. Happy to answer

questions about the tuning math or the conversion process in the

comments.

## Credits

Design, testing, and all the physical building/iteration by me.

OpenSCAD source developed with the help of Claude (Anthropic).

The "low tech" tinwhistle guide: https://www.guidogonzato.it/whistle/