Punch card pipe organ

Punch card pipe organ

A while ago i saw a pipe organ playing music from punch cards, by using the holes in the cards to activate the different pipes. You can see an example for this in the following video:

I wanted to make a simplified version that you could 3D print and play by blowing into an air inlet or placing a ballon over it. The current version has a range of one octave (12 half-tones). The dimensions where derived by averaging measurements for other pipe organs i found online:

Between the inlet and the pipes is a slit in order to slide the punch card in. I am currently trying different materials for the punch cards in order to minimize wasted air (this is a big problem with the printed punch card, rubber foam is promising). Therefore the distance between the inlet and the pipes has to be adjustable so i am using M3 heated inserts.

Problems to solve:

1. Make the pipes more efficient: the pipes currently need a rather high airflow to make a clear sound
2. Optimize restrictions to the airflow: in order to fit all notes in an acceptable space I used 4mm holes with a 1mm wall between them, which restricts the airflow considerably (see Problem 1).
3. Materials for the punch cards: I am looking for materials that will slide well between the PLA-surfaces while at the same time seal the covered holes well in order to reduce wasted airflow. 

If you like this idea and have an idea how to fix the problems feel free to use the STEP-Files to try them out or send me a message! I would love to get some help and input from fellow makers.