by Pete Kosel
with modifications and improvements by Johannes Riedl

There are now two versions of the flutomat calculator, this version for 8-hole flutes and another for 6-hole flutes.  The 8-hole version actually has 6 finger holes and 2 "vent" holes that are normally not fingered but exist to make the lowest two notes (played with 5 and 6 finger holes covered) sound more similar to other notes.

Units of measurement: cm inches
Pipe Dimensions:
Inside Diameter Wall Thickness 
hole type frequency  diameter calculated distance
from end of flute		 finger spacing local
cutoff frequency
embouchure  --------- 
finger hole 
finger hole 
finger hole 
finger hole 
finger hole 
finger hole 
vent hole 
vent hole 
(end of flute)  --------- 

Instructions
1.  Enter inside diameter and wall thickness of your pipe.
2.  Enter desired playing frequencies in hertz (i.e. cycles per second) or use the key selector to set frequencies automatically.
3.  Enter desired hole sizes.
4.  Press "calculate" button.
5.  Examine results.  Holes more than 1.25 inches apart may be hard to reach.
6.  Enter different hole sizes (smaller to move up the flute, bigger to move down toward end-of-flute).
7.  Press "calculate" again, try various hole size schemes until you're happy.
8.  Print page or write down the results, get out your drills, build your flute.
Tips: Use big holes, especially for high notes.  Drill the embouchure hole so blown edge meets pipe surface at about 45 degree angle.  Use smaller pipe for high pitched flutes and picollos, larger pipe for instruments that play lower.  For oval embouchure holes, use diameter of a circle with same area in calculations.


Dimensions of Some Common Types of Plastic Pipe in the U.S. 
Schedule 40 PVC and Steel Pipe
Nominal   Outside  Inside    Wall
Diameter  Diameter Diameter  Thickness
1/2"      0.840"   0.622"    0.109"
3/4"      1.050"   0.824"    0.113"

Schedule 80 PVC and Steel Pipe
Nominal   Outside  Inside    Wall
Diameter  Diameter Diameter  Thickness
1/2"      0.840"   0.546"    0.147"
3/4"      1.050"   0.742"    0.154"

"Copper Tube" Series CPVC Pipe
Nominal   Outside  Inside    Wall
Diameter  Diameter Diameter  Thickness
1/2"      0.625"   0.469"    0.078"
3/4"      0.875"   0.695"    0.090"

Green PPR Pipe in EU
Nominal   Outside  Inside    Wall
Diameter  Diameter Diameter  Thickness
1/2"      2.0cm    1.32cm    0.34cm
3/4"      2.5cm    1.66cm    0.42cm
1"        3.2cm    2.12cm    0.54cm






Decimal Equivalents of Some Fractional Drill Sizes
1/32 = 0.03125    9/32 = 0.28125
1/16 = 0.06250    5/16 = 0.31250
3/32 = 0.09375   11/32 = 0.34375
 1/8 = 0.12500     3/8 = 0.37500
5/32 = 0.15625   13/32 = 0.40625
3/16 = 0.18750    7/16 = 0.43750
7/32 = 0.21875   15/32 = 0.46875
 1/4 = 0.25000     1/2 = 0.50000
     





Pete's page of successful designs and tips.
Pete's E-mail: ph_kosel@cwo.com