Dyi expression pedal

[Cristian Jorge Amadeo Kus]

Hello,
I''d like to make a Arduino based expression pedal. I've already got the electronic part working, if anyone is interested i can share the link. Now i'm thinking on how to do the pedal itself and the machanical parts. I have some mouldable plastic (melts at 60 degrees) and some wood i can use. In particular i'm not sure where to get the pivot, and how to fix it to the pedalboard(32 notes BDO concave radial)
The idea is something like this: http://www.pedamidikit.org/PMK_files.../pmkswshw1.gif
Any advice on where to get the pivot ?
thanks

[bnelson218]

Just curious about how you're actually attenuating the volume. I assume the pedal will actuate a pot which then feeds the Arduino's analog input, and then what? Are you then controlling a digital pot, such as an MCP4131 IC? I love the Arduino tech and have been working on similar ideas, using digital pots to provide sustain and decay for various effects. And it's something to do when you're retired and have lots of spare time.
Every organ mfg had their own mechanisms for operating a potentiometer off the exp pedal's movement, like gears or belts. Of course, controlling the raw audio with a potentiometer has its own problems, such as wear and tear on the pot's components causing static and intermittent operation, which is why, I assume, you're after digital control of the audio.

Another idea for your exp pedal might be to find an organ that used LDRs in its expression pedal, such as Late-model Hammonds like the H100, X77, Concorde, Commodore, and Elegante. Some of their later model sprints, I believe, also used LDRs, but I'm unsure of what exact models those were. If unaware, an LDR is a light dependent resistor. Its resistance changes as more or less light is shown on it. The expression mechanism consists of the LDR in combination with a light source (typically a 6 volt bulb) and a shutter. Again, the resistance changes could be read by the Arduino's analog input to adjust the digital pot accordingly. One advantage in using this type of pedal is that the LDR and shutter mechanism are pretty well incased within the pedal assembly and not visible as opposed to pedals that actuate a pot and have external gears or belts or other linkages showing.
Good luck and keep us posted on your progress.

[musicmaker84]

I appreciate your effort, but some things might be easier to come by when purchased? I find the Moog expression pedal I use for my VTO and other musical setups to be great value for money. It cost around $50 but seems to be durable and could be attached by some means to a full pedal board, I believe. I don't recall the exact model name or number, but I got it on Amazon.