I have been on a journey to find a simple, cheap and robust design for an expression pedal. With a desire to make 5, I did not want to shell out $50 x 5 minimum, so for several months I tried several hackups, and now I can finaly post my final outcome.
Important to note, I am keeping the details extremely simple and short with room for all to consider their own alternatives and or addons etc..
Get yourself some Water pipe fittings..
The ones I chose, 2 elbows and a link peice (chrome) of course the inner and outer threads match.
Link them together..
I guess this seams obvious, but when threading them together, the chrome link peice is not tightened to either, it is left somewhat loose to rotate.
Prepare board for mounting pipes..
My method, drill 2 holes lined up with the center of the elbows where I drilled holes in the bends of the elbows, then I made 2 posts, aluminium tube with plastic lugs inside.
Prepare foot peice..
With some pipe mounting brackets mount the center chrome peice againts the foot peice.
Bring the peices together..
Mount the center of the elbow peices over the posts, and screw in through the top of the elbow.
Finish peice from top view..
You can see the screws mounted in through the top of the elbow into the posts.
And I glued on a peice of rubber mat.
And a side view to get an overall view..
It pivots, if you want the pivot to be looser or firmer, just change the alignment of the elbows to add or reduce friction on the threads.
I have even thought of many other popssible wierd setups using other shapes of pipe fittings that could be for experiment on a rainy day.
I have left out how to add a potentiometer, because there are probably thopusands of ways, so I think this is best left out, but more than happy to discuss options and maybe many methods could be added here.
My method will simply be a 6cm slide pot on a 45 deg angle with a libnk connected to the foot peice to adjust.
Will post pics of the 5 pedal setup when complete. Have all the parts, only cost about $75, just need to put it together..