Wondering around the university I found a suspicious "Top Secret" cardboard folder, probably another cheap ad to attract students. To my surprise, it turned out to be a cardboard turntable, made to manually reproduce a 45 rpm vinyl with some kind of musical puzzle inside. What a wonderful way to recruit students!
I was eager to check the contents of the record. However, when I tried to play it, the cardboard turntable showed some tuning problems which made the task of listening the high notes a misery. Since I love mysteries and crafting, I decided to build my own with paper, hoping to get better results, and so I did!
Repeat the whole process in the last step with another sheet to get the other side. Take into account that this time it should be the complementary of the base figure. This can be achieved in two ways (which are the same):
Using two sheets instead of one increase the stiffness of the structure and creates an space between layers that might help the resonance needed to reproduce the vinyl.
Ideally, this should be done in the middle of the section, but it's fine if you do it by eye, since the record is a radial surface and its going to pass through the needle anyway. I refused to fold the paper in half to get the right point because that could affect the resonance of the paper afterwards.
In case the needle doesn't hold in its place after a while, due to use or trying to correct the piercing direction, a bit of tape can be applied to fix the needle to the paper.
It's a bit tricky to use, since you have to hold it tight by pressing to the table to avoid inconvenient movements. It's useful to bend the folds again if the needle goes forward while playing.
The results were quite satisfactory, since the paper version was a bit more sensitive when playing the hidden code of the record, which have different notes and pitches not reproduced by the default cardboard version.The cardboard one was louder, but that's probably an effect of the bigger size, rather than the material used.