USB Keyboard to Pedal Board Build

Built from a USB keyboard, 18 buttons, aluminum plates from a few power amps cabinets.

I needed a USB based foot controller with plenty of buttons so I decided to create one after reading and seeing several versions on the web.

 

Items required

 

 

One of the designs I seen was build using an existing pedal board and a USB keyboard circuit. They used an old Apple keyboard which the board was a good size but they did manage to use 10 characters of the keyboard and added 5 more buttons to the pedal board. The advantage of the older style board is there are solder points where you can connect wires, I will cover this later.

 

Sizing the board

 

In order for my foot to reach a button and not hit the button next to it I need a minimum of about 4 to 4.5 inched which was about 2 to 2.25 inches of center. I also had to figure the distance from the next row.

 

I thought if I offset the buttons I could get more, but after drawing it out, it did not work because of what I call foot displacement.

The foot covers more buttons which could lead to an accidental push depending on angle which we will cover later.

With a uniform pattern the foot can press a single button with less chance of pressing other buttons. And both layout have 18 buttons.

 

The angle of resistance

 

Somewhere, someone figure out the terms for this but I call it angle of resistance. The angle of an object in relationship to the object that is contacting it either downward or forward force or a portion of both.

 

If I leave the board flat or almost flat I will not have to worry about it sliding or turning over when I push the button. The downside is the board will take up more room on the floor. Many guitar pedal boards for instance have a low profile which means you push down on the button and it helps with storage.

 

I played around with different angles to find what was comfortable, increasing the angle reduced the floor space by about 3 inches.

 

Be careful not to get it too steep as it will tend to turn over or slide on the floor.

 

Case Material

 

I had an old non working PA amplifier which has some large covers, these turned out to be just the right size and are aluminum. The top and bottom panels on this a are 12″ x 17.25″ and the front panel was 5.25″ x 19″.

 

I cut the front panel to match the  width of the 17.25″ of the other panels. The bottom panel was cut and reduced to 9″ x 17.25″ and the top was not cut, but the front edge was rolled over to produce a mounting point for the bottom cover and stiffens the top panel. It reduced it to 10.25″ x 17.25″.

The side I made out of 3/4″ cabinet plywood stock of hard wood and cut to shape.

I then used several coats of sanding sealer and black paint to finish it. It looks like metal and has a very hard finish that will put up with a lot of use.

Foot Buttons

 

I ordered my momentary switches from bitcheslovemyswitches.com. I measured and layout the button pattern on the panel and drilled the 18 holes to size.

Mounted each switched and wired.

Locating Components

 

I took some time to figure out the best placement for components in regards to what needed access.

The flash card on the Raspberry Pi board I would need access too if I had to reloaded software to it or I would need access it. I installed 2 ports on the back. One is the HDMI and the other is a USB port to connect keyboard and/or mouse. These 2 port plus the access to the flash card gives me what I need unless I need to connect it to the network. The DMX ports are located near the floor and the power switch and plug.

 

Note: If I were to change the setup I would have a small pig-tail cable from the DMX output or I would recess it more. With the cable being directly plugged in, it sticks out and could be stepped on which would break the DMX port.

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