Facility: tetrahedron studio laboratory workshop archive shop documentation center

Logos Instrument Building Workshop

PVC Project

commissioned by Musica vzw (2015-2017)

  • P: Polyphonic / Polyfoon / Projekt / Plastiek / Plastisch
  • V: Versatile, Variable, Verplaatsbaar
  • C: Contraption , Concertinstallatie/ Concertinstrument / Concertant


The idea is to design and build a modular yet consistent instrument using PVC material that could be played by many children in togetherness. The instrument should be transportable in a small van and mounting complexity should be low and take up a minimum of time. Sturdiness is essential as well as safety. Weather resistance was also a design issue.

  • - 24 drumpipes / klopbuizen (tunable to many systems) Two modules, each one and a half octave.
  • - 2 Intonarumori (friction drums derived from noise makers as build by Luigi Russolo)
  • - 4 Kalliopes (derived from the design of 19th century steam whistles)
  • - 2 Singing Bicycles (an invention by Godfried-Willem Raes) adapted to use on modified home trainers
  • - 2 jumping rods (threaded rods mounted on a membrane, on which rings can rotate by gravity)
  • - 1 large friction drum (derived from instruments such as the quica, rommelpot, Waldteufel, Loewengebruell etc...)
  • - Whispers (Cavity resonators)
  • - Log drums
  • - Rommelpotten
  • - Balg of pomp gestuurde schuiffluiten

Realisation / Realisatie:

1.- Twee modules met elk 12 klopbuizen voorzien van opzetstukken waarmee de tonen kunnen worden gekozen. Bij elke module hoort een houder voor de ping pong paletten voorzien van een speciale laag zacht neopreen.

2.- Twee Intonarumori instrumenten met membraan, spanmekanisme en door een zwengel bediend strijkwiel.

3.- Een module met vier kalliopes voorzien van vier balgen en verbonden met witte flexibele PVC buizen. De module is in hoogte verstelbaar.

4.- Twee home-trainer zingende fietsen, elk met twee resonantiebuizen in PVC

5.- Twee draadstang modules met membraan ringschrijven en omkeermekaniek. (omgebouwd tot rommelpotten in 2017)

6.- Twee rommelpotten (2017)

7.- Vier schuiffluitmodules (2017)


Earlier projects and compositions by Godfried-Willem Raes using PVC pipes:

Collaborators in the realisation and construction of this project:

  • Mattias Parent (PVC research and construction)
  • Laura Maes (project supervision)
  • Godfried-Willem Raes (metal and welding works, structural design, research)

Construction diary:

15.07.2014: Sketches for what mechanisms could be made using PVC pipes:

01-16.02.2015: Experiments carried out with different kinds of PVC. The idea to make PVC logdrums came out to be unworkable. So this design was cancelled from the list of possibilities.

17-18.02.2015: Construction of drums using large diameter PVC pipes by Mattias Parent. Although this works very well, we did not preserve them in the final project by lack of originality. The drums may be modified to large lions roars later.

21.02.2015:Construction of an experimental giant whisper, using vinyl LP records

02.05.2015: Singing bicyle, with two tones mounted on a home trainer:
25.05.2015: Scale 1:1 technical drawing made for the construction of the intonarumori.
26.05.2015: Welded base and mechanics for the first intonarumori instrument, using 400 mm diameter thick PVC pipe: Here is a detail of the crank and the friction wheel: The legs are made from two lengths of 1 m 1/2" gaspipe, bend under 90 degrees using the Ridgid hydraulic pump and welded to the base 50x30x3 profile. The PVC pipe mounts on the stand with three M12 bolts.

27-28.05.2015: Further work on the string tending mechanism in nylon and definitive mounting of the crank. Definitive studbolt mounted for limitation of the range for the tending mechanism.

30.05.2015: A new load of PVC pipe cames flowing in...

02-04.05.2015: Construction of the bellows for the kalliopes

06-07.05.2015: Construction of the second intonarumori instrument.

10-15.06.2015: Cutting, drilling and TIG-welding works on the hexagonal holding structures for the tube resonators. Each module will hold 12 tubes, 90 mm in diameter. The diameter of the complete module will become 1100 mm. There are two such modules, so in total 24 tubes.

16.06.2014: Mounting of the PVC tubes in the structure. The first of these modules is ready and playable... Welding of the T-stands for the two jumping rods. (50x30x3 steel and 25x25x1.5) The distance holder rods between the stands still has to be welded in. We first have to know how to rotate the mechanism.

17.06.2015: Different kinds of neoprene and rubbers tested for the construction of the playing pallets.

18.06.2015: Two modules ready. All exchangeable pipe lengths sawn off and tuned. Design alternatives for the kalliopes drawn out and studied.

19.06.2015: Welding and final construction works on the second intonarumori instrument. This will be made from orange sewer pipe PVC,

20.06.2015: Sawing, precision drilling and welding of the steel holder for the four kalliopes. These will be mounted on a sturdy tripod such that the height can be adjusted. The kalliopes are mounted on the structure in a vertical position.

21.06.2015: Painting of the welded construction. Mounting of the kalliopes. Construction and adjustment of the mounting brackets. First tests with the bellows.

22.06.2015: Finalising the construction of the threaded rod instruments: clamping mechanism and welding of the studs connecting both T's pieces. The painting still has to be done. And here is a picture of both beat-tube/ drum-pipemodules together:

23.06.2015: Finishing of the second intonarumori instrument.

24.06.2015: Final painting of all modules. Construction of the beaters for the drum-tubes. Instrumental setup demonstration for Musica.

25.06.2015: Printing of the labels with the pitches for the pipes. Further construction of playing pallets. Design and construction of two holders for the ping-pong pallets.

26.06.2015: Transport of the project to Musica in Limburg. Setup and installation Laura Maes and Mattias Parent at Alden Biesen. Some issues to be remedied are: the bikes are too loud in comparisson to the other modules. The threaded rods are too gentle. The first issue can be solved by placing a series resistor in the wires to the speakers. The second one, to replace the ring with heavier ones and to exchange the membrane with styrofoam.

28.06.2015: Premiere of the project at AlbaNova organized by Musica at Alden Biesen.

2016: Parkbos installatie:

}10-13.08.2017: Construction of two easy to play lions roar modules: [Konstruktie van twee rommelpotten:| These use a wooden wheel with bow rosin (collophonium)

14.08-18.08.2017: {Konstruktie van de eerste twee schuiffluit modules:} Construction of the two highest bellow-blown slide whistle modules. Although it would have been a lot easier to just make mouth blown slide whistles, we rejected the idea for hygienic reasons. The bellows use Jobe double action hand pumps. Due to the fact that their wind outlet is in de handgrip, we had to mount them upside down. These bellows have 2 x 2 liter air content, this allowing pretty long sustained notes. Maximum air pressure is 1.9 Bar. The PVC pipes for the flutes are 25 mm in diameter. The sliding end-stop plunger is made of Epramid staff material, turned to size on the lathe. Here are some details:

19.08.2017: Design of the lower slide whistles. Here we are using much larger pumps. So we selected Quechua pumps with an air content of 5.2 liters. The flue pipes in this case were a lot more difficult to make, as we had to make the slide-piece and the flute block completely from scratch. In fact we used a piece of aluminum tube turned on the lathe and filled with epoxy rosin (Seno 4046, produced for the encapsulation of electronic circuits). The epoxy compound needs 24 hours to cure, so we had to interrupt the works and just wait...

20.08.2017: Further construction of the slide whistles.The bass whistle uses a PVC tube, 40 mm x 1.8. The sliding plunger thus has to be just a bit (ca. 0.2 mm) smaller than 36.4 mm. This plunger was fabricated using aluminum tube filled with epoxy rosin. The result is not too great, as gently sliding remains problematic, even when greased with vaselin. Apparently the PVC tube itself is not pure cilindric... The larger pumps used to drive this whistle give some problems as well, as their movement is not very fluent neither. They do not seem to work as well on low pressures as the Jobe pumps used for the smaller pipes.
21.08.2017: Construction of handgrips for the large red pumps, as their diameter is too large to be easily taken by childrens hands. The grips made of Teflon (PTFE), giving a very smooth and nice feel. Here are two pictures:

22.08.2017: Construction of the tenor slide whistle. Here we will use 30 mm diameter PVC pipe. The slider can be made from massive brass rod, 28 mm diameter. The block for the flue is made from massive PVC and turned to size on the lathe. The grid used for this module will be green glassfibre fabric. The blocks preventing sideways movement of the pump are made from massive 30 mm thick PVC material. This is certainly an improvement over earlier designs, although more expensive to fabricate.
23.08.2017: Finishing the tenor slide whistle. Construction of the pumps handle. Construction of the slide mechanism with aluminum handle. Construction of the end-stop with venting holes. Construction and mounting of the fingerboard. All four slide whistles are now ready to be presented by Musica...
24.08.2017: All four whistles delivered to Musica.


Todo: add musical scales to the fingerboards on the slide whistle modules

Last updated: 2017-08-24