You used to find in the back of Guitar Mag advertisements for pedal ' blanks', empty pedals with a pot already mounted. The problem back then was add $10-15 plus shipping and you could just buy a comercial one. Got to love the thinking in the mid-late 80s. Check the China sites to see if you can find the volume pedals.
Don't worry about the pot not turning through a large range of angles. You can use the map() function to output whatever range of values you need based on any input range
You could 3D print a roller and mount to push the rack closer to the gear, but if that's not good enough you could cut out all the bad stuff and 3D print new modified stuff to replace the bad parts and just glue/screw them in place.
About the pedal and the pot problem... You could use and infrared led emitter and receiver and attach a piece of plastic to the pedal that slips between them that goes for fully transparent to black. Berhinger is using such a desing in the X V-Amp guitar pedal.
That pedal is ridiculously cool. The meshing part could probably be fixed easily but the gearing is probably a deal breaker. I'm guessing you could build something out of wood that would meet your needs a little better. Then my next thought is that you could use something like a MCP4131 digital potentiometer chip and a rotary encoder. That would get rid of your need for the pot to have any sort of specific turn because you could set the ratios in software. There are good arduino libraries and examples for that chip. But most of all, thanks for the midi primer. I've been around it all my life but other than a little software tinkering, I've never used it.
An idea I've been toying with is to do away with moving parts all together. Get one of those ultrasonic range detectors, mount it facing upward through an aperture in the pedal then just move your foot up and down above it as if there was a pedal. Simples. The arduino will have a library for it, just replace the a/d code in your program with the digital read from the sensor.
@@pileofstuff A while since I played with them but as they are used as collision avoidance in robotics I would imagine they would be. I seem to recall max range is around a meter. I am planning to try to use them in the modern version of a theramin!
Ditch the mechanical and rig up a hall effect on the pinion. no more dirty pots either. or constrain the limited rotation you are getting with current setup. ie 25% rotation to the 127 values. cool project1
Perhaps the top of the rack, where it joins the step, should be on a pivot, and the bottom of the rack should be lightly tensioned against the pinion with a small spring.
Two suggestions: Fix the poorly meshing gears with a stiffener glued on the back of the rack (rack and pinion). The stiffener would be at right angles to the back of the rack, the hole in the pedal base would be changed from a slot to a tee. Change the map statement (it would be helpful if you turned on line numbering in the IDE) visible at 5:30 to cover as much of the pot range as necessary. Hopefully that's a linear pot. Tony.
Good video! :-) here's an idea you can do what I did a long time ago, I picked up an old volume pedal from a junk place, and made it into a wah-wah pedal using a flanger schematic that I modified. But for your case you would just really need the volume pedal itself and then you can put your electronics into it. That would be more convenient than the long hours of printing out something that may not work. :-)
I would use a string and move the pot to the end. Extend the pot nobe so you can add two pieces that the string can rap around. If that doesn't work then start again with something else that looks promising
Could have split the ground box halfway and added some interior overlap aiding in sticking it together. Can still add an interior layer tall enough to strengthen the case and at the same time hold the rack pin against the gear.
Very nice project. I have been tinkering with 3D printing as well. I think the top gear is not as strong as it should be and is flexing away from the gear attached to the potentiometer. Would you be able to adjust the angle towards the potentiometer gear by using a heat gun? Could you add a metal support (i.e. piano wire heated and imbedded into the plastic) to prevent this from flexing in use? I am looking forward to how you solve the problem! I used the timing belts on a CNC machine and it worked great. It would be pretty easy to use that as a solution as well. Too bad 3D printing takes so long and has a few problems while printing. I have found a RC Aircraft iron to help with the rough areas. This iron was used to iron on mono-coat on the plane wings and other panels. It works quite well as a 3D print cleanup device.
There should be a way to translate your min and max values from the pot to the full 0-127 midi range. Mechanically, it looked like it meshed with pressure on the rack from behind, how about a lump of nylon back there or a small skate wheel, or if you want to change the model, just curve the rack at a larger radius (I say just.... Not used the software...) Great project. I hate 5 pin din. Almost as much as I hated soldering 37 pin d-type y-splits
Have you thought about a slide potentiometer and a mechanism to work it? Maybe alter the foot pedal with the slide pot going up and down? It could eliminate the rotary pot problems you are having now. And don't electric guitars have a bar you can jiggle that does the same thing?
I've never worked with 3D printed parts but would worry that a 3D printed pedal would break in gigging conditions. I have made a similar device to your Arduino using an ATTiny85 which converted the pedal resistance to various MIDI CC messages but used a commercial Yamaha FC7 as the input device. The Yamaha FC7 is very sturdy but has a very long throw so am not sure how suitable it is for a wah effect. The good news is that you can modify the response curve in the Arduino software!
Well, I would just change the design or just redraw it better. When you just add a little support on the inside of the underpedal to guide it and make the piece that goes in a couple of teeth longer it will probably just fine. And then change the software a bit for higher outputnumbers so you can use smaller movements of the pot. For printing, I'm sure i would print something like this in another direction like on its top so that the bridges go to the inside and still maintaining strenght (and you can print in one piece) or on a bigger printer on its side. Actually, rotating the object to print under 45 degrees from the bed gives you probably enough lenght or just scale it a bit in the slicer since this pedal seems to be very large compared to the ones I have here for my guitar and keyboard. Interesting project! add: I guess you can also use a pedal for a sewingmachine for this. They are also using (big) pots in those and they are made to last. A pot like you have now will probably not last many hours of movements if you'd consider to really use it.
@@pileofstuff the map() function itself doesn't constrain the input value to within the input range, so if you supply an input value outside the input range (say, the A/D logic spits out noise for some reason) to map(), the result will be outside the output range. Using constrain() on map()s result will at least keep you from possibly confusing the MIDI code with invalid data. Pots are notoriously eventually noisy, and if you've altered the map() function to handle a narrowed range of values because you're using a limited arc on the pot, the A/D value as read from that pot will eventually, randomly be outside that arc and spit out a value that will map() outside the output range.
One strange thing about your schematics is that usually, you would not want to connect a common ground trough your MIDI connector in order to prevent ground loops... (sorry, MIDI out does have a ground, its the MIDI in that doesn't have the common ground connected... my bad)
You used to find in the back of Guitar Mag advertisements for pedal ' blanks', empty pedals with a pot already mounted. The problem back then was add $10-15 plus shipping and you could just buy a comercial one. Got to love the thinking in the mid-late 80s. Check the China sites to see if you can find the volume pedals.
Don't worry about the pot not turning through a large range of angles. You can use the map() function to output whatever range of values you need based on any input range
You could 3D print a roller and mount to push the rack closer to the gear, but if that's not good enough you could cut out all the bad stuff and 3D print new modified stuff to replace the bad parts and just glue/screw them in place.
About the pedal and the pot problem... You could use and infrared led emitter and receiver and attach a piece of plastic to the pedal that slips between them that goes for fully transparent to black. Berhinger is using such a desing in the X V-Amp guitar pedal.
That pedal is ridiculously cool. The meshing part could probably be fixed easily but the gearing is probably a deal breaker. I'm guessing you could build something out of wood that would meet your needs a little better.
Then my next thought is that you could use something like a MCP4131 digital potentiometer chip and a rotary encoder. That would get rid of your need for the pot to have any sort of specific turn because you could set the ratios in software. There are good arduino libraries and examples for that chip.
But most of all, thanks for the midi primer. I've been around it all my life but other than a little software tinkering, I've never used it.
An idea I've been toying with is to do away with moving parts all together. Get one of those ultrasonic range detectors, mount it facing upward through an aperture in the pedal then just move your foot up and down above it as if there was a pedal. Simples. The arduino will have a library for it, just replace the a/d code in your program with the digital read from the sensor.
Interesting. I wonder if they are sensitive enough at close range?
@@pileofstuff A while since I played with them but as they are used as collision avoidance in robotics I would imagine they would be. I seem to recall max range is around a meter. I am planning to try to use them in the modern version of a theramin!
Ditch the mechanical and rig up a hall effect on the pinion. no more dirty pots either. or constrain the limited rotation you are getting with current setup. ie 25% rotation to the 127 values.
cool project1
There's an interesting idea. I think I've even got a few hall effect sensors around here somewhere...
All of the foot pedals that I ever saw had the light being interrupted between an LED and a photodiode
@@wooferhound7571 Wouldn't that just be an on/of though?
You might also try low voltage sewing machine pedals, Kid's toys and such.
Interesting idea. I'll add that to my search terms.
Perhaps the top of the rack, where it joins the step, should be on a pivot, and the bottom of the rack should be lightly tensioned against the pinion with a small spring.
Two suggestions:
Fix the poorly meshing gears with a stiffener glued on the back of the rack (rack and pinion). The stiffener would be at right angles to the back of the rack, the hole in the pedal base would be changed from a slot to a tee.
Change the map statement (it would be helpful if you turned on line numbering in the IDE) visible at 5:30 to cover as much of the pot range as necessary. Hopefully that's a linear pot.
Tony.
Use elastic to tension the rack, then find the lower and upper value that get output from the pot, and scale accordingly
Good video! :-) here's an idea you can do what I did a long time ago, I picked up an old volume pedal from a junk place, and made it into a wah-wah pedal using a flanger schematic that I modified. But for your case you would just really need the volume pedal itself and then you can put your electronics into it. That would be more convenient than the long hours of printing out something that may not work. :-)
I would use a string and move the pot to the end. Extend the pot nobe so you can add two pieces that the string can rap around. If that doesn't work then start again with something else that looks promising
It must be MIDI Foot Pedal week - Adafruit just shared a design a couple of days ago.
I'll have to check it out . Thanks for letting me know
Could have split the ground box halfway and added some interior overlap aiding in sticking it together.
Can still add an interior layer tall enough to strengthen the case and at the same time hold the rack pin against the gear.
Very nice project. I have been tinkering with 3D printing as well. I think the top gear is not as strong as it should be and is flexing away from the gear attached to the potentiometer. Would you be able to adjust the angle towards the potentiometer gear by using a heat gun? Could you add a metal support (i.e. piano wire heated and imbedded into the plastic) to prevent this from flexing in use? I am looking forward to how you solve the problem! I used the timing belts on a CNC machine and it worked great. It would be pretty easy to use that as a solution as well. Too bad 3D printing takes so long and has a few problems while printing. I have found a RC Aircraft iron to help with the rough areas. This iron was used to iron on mono-coat on the plane wings and other panels. It works quite well as a 3D print cleanup device.
Maybe use a bit of op amp action to translate the limited range of the potentiometer into the full voltage range that you require.
There should be a way to translate your min and max values from the pot to the full 0-127 midi range.
Mechanically, it looked like it meshed with pressure on the rack from behind, how about a lump of nylon back there or a small skate wheel, or if you want to change the model, just curve the rack at a larger radius (I say just.... Not used the software...)
Great project. I hate 5 pin din. Almost as much as I hated soldering 37 pin d-type y-splits
Have you thought about a slide potentiometer and a mechanism to work it? Maybe alter the foot pedal with the slide pot going up and down? It could eliminate the rotary pot problems you are having now. And don't electric guitars have a bar you can jiggle that does the same thing?
Interesting to hear how long it took to 3D print the box. I have made an almost identical pedal out of 3mm plywood in about half an hour.
take 2 gears and used the same box . or change the number of teeth on gear and down pedle.
I've never worked with 3D printed parts but would worry that a 3D printed pedal would break in gigging conditions. I have made a similar device to your Arduino using an ATTiny85 which converted the pedal resistance to various MIDI CC messages but used a commercial Yamaha FC7 as the input device. The Yamaha FC7 is very sturdy but has a very long throw so am not sure how suitable it is for a wah effect. The good news is that you can modify the response curve in the Arduino software!
Well, I would just change the design or just redraw it better. When you just add a little support on the inside of the underpedal to guide it and make the piece that goes in a couple of teeth longer it will probably just fine.
And then change the software a bit for higher outputnumbers so you can use smaller movements of the pot.
For printing, I'm sure i would print something like this in another direction like on its top so that the bridges go to the inside and still maintaining strenght (and you can print in one piece) or on a bigger printer on its side. Actually, rotating the object to print under 45 degrees from the bed gives you probably enough lenght or just scale it a bit in the slicer since this pedal seems to be very large compared to the ones I have here for my guitar and keyboard.
Interesting project!
add: I guess you can also use a pedal for a sewingmachine for this. They are also using (big) pots in those and they are made to last. A pot like you have now will probably not last many hours of movements if you'd consider to really use it.
How about using the mechanics of a bass drum pedal? It has what you need...pedal to rotary motion. Just a thought.
That's another possibility, if I can find one cheap.
What about creating some kind of grey disc / optical sensor to get the full range of travel
Interesting idea
@@pileofstuff or maybe use a rotary encoder instead of a potentiometer
how's about a sewing machine pedal ?
tweak the design so the rack work as a spring against the gear, to get bigger range make that gear smaller
Yep, pretty sure you could loose that constrain line with no I'll effects :)
Probably.
I'd like to understand why the demo author thought it was important enough to include, though.
@@pileofstuff the map() function itself doesn't constrain the input value to within the input range, so if you supply an input value outside the input range (say, the A/D logic spits out noise for some reason) to map(), the result will be outside the output range. Using constrain() on map()s result will at least keep you from possibly confusing the MIDI code with invalid data. Pots are notoriously eventually noisy, and if you've altered the map() function to handle a narrowed range of values because you're using a limited arc on the pot, the A/D value as read from that pot will eventually, randomly be outside that arc and spit out a value that will map() outside the output range.
Why not use a slider instead of a rotary pot?
interesting thought
One strange thing about your schematics is that usually, you would not want to connect a common ground trough your MIDI connector in order to prevent ground loops... (sorry, MIDI out does have a ground, its the MIDI in that doesn't have the common ground connected... my bad)
How about a linear pot?
Buy a whapedal
Kinda ignores the fun challenge of making something, though.