Siku (Zampoña) — Print Packet

Heifer Zephyr · instrument-maker-v4 · packet v4.3 · 2026-05-08
Instrument: Siku (Zampoña) — Andean Panpipe, Four-Member Family
Primary build target: Zanka (key of C, tenor, bore ⌀0.625")

Quick Reference

Parameter	Value
Tube length formula	`L_calc = 13552 / (4 × f_hz) − 0.82 × bore_ID`
Trim allowance	`L_cut = L_calc + 3/16"`
Speed of sound	13,552 in/s at 68°F
Tuning standard	A4 = 440 Hz, equal temperament
End correction	0.82 × bore_ID (empirical)
Pipe type	Stopped cylindrical; odd harmonics only (1f, 3f, 5f…)

Family Tube Dimensions

Toyo (Bass · G3 root · bore 0.750" · OD 1.000")

Tube ID	Rank	Note	Hz	L_calc (in)	L_cut (in)
T-A1	Arka	G3	196.00	22.459	22.646
T-I1	Ira	A3	220.00	19.958	20.146
T-A2	Arka	B3	246.94	17.742	17.929
T-I2	Ira	C4	261.63	16.709	16.896
T-A3	Arka	D4	293.66	14.820	15.007
T-I3	Ira	E4	329.63	13.139	13.327
T-A4	Arka	F4	349.23	12.378	12.565
T-I4	Ira	G4	392.00	10.979	11.166
T-A5	Arka	A4	440.00	9.629	9.817
T-I5	Ira	B4	493.88	8.546	8.733
T-A6	Arka	C5	523.25	8.054	8.242
T-I6	Ira	D5	587.33	7.128	7.315
T-A7	Arka	E5	659.26	6.267	6.455

Frame width (Toyo): 13.750" · Pocket pitch: 1.063" C-C · Pocket width: 0.995"

Zanka (Tenor · C4 root · bore 0.625" · OD 0.821") ← Primary Build

Tube ID	Rank	Note	Hz	L_calc (in)	L_cut (in)
Z-A1	Arka	G3	196.00	16.961	17.148
Z-I1	Ira	A3	220.00	15.076	15.264
Z-A2	Arka	B3	246.94	13.395	13.582
Z-I2	Ira	C4	261.63	12.620	12.807
Z-A3	Arka	D4	293.66	11.157	11.344
Z-I3	Ira	E4	329.63	9.878	10.065
Z-A4	Arka	F4	349.23	9.292	9.479
Z-I4	Ira	G4	392.00	8.231	8.418
Z-A5	Arka	A4	440.00	7.188	7.375
Z-I5	Ira	B4	493.88	6.447	6.635
Z-A6	Arka	C5	523.25	6.060	6.247
Z-I6	Ira	D5	587.33	5.328	5.516
Z-A7	Arka	E5	659.26	4.627	4.814

Frame width (Zanka): 11.423" · Pocket pitch: 0.884" C-C · Pocket width: 0.816"

Malta (Alto · G4 root · bore 0.500" · OD 0.658")

Tube ID	Rank	Note	Hz	L_calc (in)	L_cut (in)
M-A1	Arka	G4	392.00	7.565	7.752
M-I1	Ira	A4	440.00	6.728	6.915
M-A2	Arka	B4	493.88	5.971	6.158
M-I2	Ira	C5	523.25	5.638	5.826
M-A3	Arka	D5	587.33	4.978	5.165
M-I3	Ira	E5	659.26	4.389	4.576
M-A4	Arka	F5	698.46	4.144	4.332
M-I4	Ira	G5	783.99	3.624	3.811
M-A5	Arka	A5	880.00	3.214	3.401
M-I5	Ira	B5	987.77	2.823	3.010
M-A6	Arka	C6	1046.50	2.669	2.857
M-I6	Ira	D6	1174.66	2.339	2.526
M-A7	Arka	E6	1318.51	2.074	2.261

Frame width (Malta): 9.304" · Pocket pitch: 0.721" C-C · Pocket width: 0.653"

Chili (Soprano · A4 root · bore 0.375" · OD 0.493")

Tube ID	Rank	Note	Hz	L_calc (in)	L_cut (in)
C-A1	Arka	A4	440.00	7.565	7.752
C-I1	Ira	B4	493.88	6.728	6.915
C-A2	Arka	C#5	554.37	5.971	6.158
C-I2	Ira	D5	587.33	5.638	5.826
C-A3	Arka	E5	659.26	4.978	5.165
C-I3	Ira	F#5	739.99	4.389	4.576
C-A4	Arka	G5	783.99	4.144	4.332
C-I4	Ira	A5	880.00	3.624	3.811
C-A5	Arka	B5	987.77	3.214	3.401
C-I5	Ira	C#6	1108.73	2.823	3.010
C-A6	Arka	D6	1174.66	2.669	2.857
C-I6	Ira	E6	1318.51	2.339	2.526
C-A7	Arka	F#6	1479.98	1.982	2.170

Frame width (Chili): 7.159" · Pocket pitch: 0.556" C-C · Pocket width: 0.488"

⚠ C-A7 (F#6, L_cut = 2.170") is at the practical playability limit. Prototype this tube first before committing production stock. Consider building Chili as 11 tubes (omit C-A7 and C-I6).

CNC Rail Parameters (All Members)

Member	OD	Pocket Width	Pocket Depth	Pocket Pitch	First Center
Toyo	1.000"	0.995"	0.333"	1.063"	0.500"
Zanka	0.821"	0.816"	0.274"	0.884"	0.411"
Malta	0.658"	0.653"	0.219"	0.721"	0.329"
Chili	0.493"	0.488"	0.164"	0.556"	0.247"

Pocket depth = OD/3 · Pocket pitch = OD + 1/16" · Z0 = top of stock

Tube Sealing — Beeswax Plug Depths

Member	Plug Depth	Stand Hole ⌀
Toyo	3/8"	1.010"
Zanka	3/8"	0.831"
Malta	1/4"	0.668"
Chili	1/4"	0.503"

Pour beeswax at 160°F. Allow 30 min cure before handling.

Tuning Acceptance Criteria

Metric	Criterion
Pitch tolerance	±5 cents of target frequency
Maximum trim	≤ 3/16" below L_calc (scrap if exceeded)
Environment	Measure and trim at same temperature
Reference	A4 = 440 Hz on calibrated chromatic tuner

Material Shortlist (Zanka Build Only)

Item	Spec	Qty	Notes
Bamboo tube stock	~0.821" OD / 0.625" bore; 18" sticks	16 sticks	Cañahueca preferred; sort by bore before cutting
Cherry S4S	3/4" × 1.5" × 12.5"	4 pcs (2 rails × 2 ranks)	Can also use walnut
Beeswax	4 oz block	1	Shared with other members
Waxed linen cord	1mm, ~80 ft	1 spool	Nylon acceptable
Danish oil	1 pint	1	For cherry rails

Assembly Checklist

[ ] Bore ID verified within +0.000" / −0.010" of target for all tubes
[ ] All 13 tubes cut to L_cut lengths from this table; labeled with tube ID
[ ] Sealing stand built (Zanka: 13 holes at 0.831" ⌀, spaced 0.884" C-C)
[ ] Beeswax plugs poured and cured
[ ] First-pass tuning complete; all deviations recorded in validation.csv
[ ] Frame rails milled; pocket width verified with first pocket before batch
[ ] Dry-fit assembly confirmed; all 13 tubes seat in pockets
[ ] Cord binding complete; square-knot finish at both rail ends
[ ] Final tuning: all 13 tubes ±5 cents; validation.csv updated
[ ] Rails finished with Danish oil; tubes wiped with tung oil

Notes

This print packet covers Zanka as primary build. Use family-spec.csv for all 4 members.
Tube lengths in this table are L_cut (include 3/16" trim allowance). Never cut shorter than L_calc.
Story stick: mark all 13 tube lengths on a 1/4" × 1" × 18" MDF strip before cutting.
Keep validation.csv open during the entire build and fill in measured_hz after each tuning pass.
See resources.md §Provenance before writing any public-facing documentation.

Packet v4.3 · tonykoop/siku-zampona · CC BY 4.0 · Heifer Zephyr

Siku (Zampoña) · packet v4.3 · tonykoop/siku-zampona · CC BY 4.0 · Heifer Zephyr