does anyonme make a variable resistance momentary stomp switch?

[big bustle]

imagine a delay with a momentary switch where the harder you push down the more feedback/delqay regeneration you get

i assume this could be built like a slider pot in a switch.

if this is made i bet it's like $20 a switch

i figured i'd ask to see if this is out there

i only need two lugs for my application and not 3

[Processaurus]

Look into force sensing resistors.  On some MPC style drum pads (thinking of M-audio's midi keyboard, the axiom series), they can be used to control something by how hard you smoosh on them.  Pretty great!  Kludging something together would be easy, making a voltage divider out of a FSR and a regular resistor, and sending that to an opamp with some trimmers to tailor the DC bias and gain to get the right control voltage.  Then send that to a VCA or LED/LDR if you are the type, and that can control your feedback.

They also do some things with cheap rubber pushbuttons where a micro processor can read how hard you're smooshing it on the carbon ink pad on the pcb, but that's a whole programming thing.  Playstation 2 and Game Cube controllers did that I believe.

[MoltenVoltage]

put a heavy spring under your wah pedal and tap into the pot

[Mark Hammer]

One traditional approach is to use something like conductive foam (the black stuff that static-sensitive chips come in) with a metal layer on top and bottom.  The conductive foam is not as conductive as solid wire, so the resistance can be altered with the amount of physical compression imposed on it.  If you have a sheet of metal foil on each side, and each sheet is connected to a wire, then resistance between the foil sheets will decrease as you press.

Easy to make, however the down-side is that the foam is not perpetually springy.  You can only squish it so often or so many times before it becomes limp and lifeless and need to replace it.  But it DOES work.

[Ripthorn]

You could also look into a theremin or a simple expression pedal where you're delay pedal would have a delay pot output jack wired in (probably a switched jack).

[puretube]

One traditional approach is to use something like conductive foam (the black stuff that static-sensitive chips come in) with a metal layer on top and bottom.  The conductive foam is not as conductive as solid wire, so the resistance can be altered with the amount of physical compression imposed on it.  If you have a sheet of metal foil on each side, and each sheet is connected to a wire, then resistance between the foil sheets will decrease as you press.

Easy to make, however the down-side is that the foam is not perpetually springy.  You can only squish it so often or so many times before it becomes limp and lifeless and need to replace it.  But it DOES work.

A certain Germann Walter and a Oskar SALA did similar stuff 75 years ago... 

[CynicalMan]

put a heavy spring under your wah pedal and tap into the pot

Or, you could have a button connected to a spring and to a pot inside the box.
I think someone did something like that using clothespins but I can't find it.

[big bustle]

thanks for all of the responses

i was hoping to find an easy to use pro solution i can install in boxes i sell to folks. the diy/home made solutions are awesome but not practical for the folks that pay good money for one of my boxes.

[Processaurus]

[big bustle]

[WLS]

A certain Germann Walter and a Oskar SALA did similar stuff 75 years ago... 

What do you mean???

...
becomes limp and lifeless ...

Sorry guys, I just couldn't resist.

Both contributions are great! Maybe in today's world Walter's and Oskar's idea would be more feasible. Since the biggest draw back seems to be the conductive liquid?


Bill

[big bustle]

i recently bought a new cordless drill that has variable speed depending on how hard you pull the trigger.

a solution you say?

replacement switches seem to run around $30 on ebay.

i have an old drill i'm considering cannibalizing to see if it will work.