Volume Pedal - Build

Guitar Volume Pedal - I was looking for easy projects to get back into soldering and electronic components. Plus a great Christmas gift.

Parts List

• 2 Audio 1/4" female jacks (purchased on Amazon)
• 1 Potentiometer 100K Ohm (purchased on Amazon) - (I plan on experimenting with this value)
• 1 Capacitor 100kpF (I had one)
• Hinge
• Wire
• Wood
• She kind of cording

I searched on the internet and found a few different pedal builds. I picked one I thought would be pretty easy. After building this one I have a lot of improvements. I will document the next build as well so you will see the differences. 

So, cut out the pieces, glued and nailed them together. The next build I will document the dimensions. Im using 1/2" plywood, and the dimensions I found online were for 1/4" hard board. So the walls on mine are thick, and crazy strong. It is an over kill.

Since it is so thick I needed to cut out the places where I wanted the 1/4" audio jacks. I used a hole saw, and cut down most of the way. That left a raised part on the inside. I drilled the center hole so that the jack would slip in. The hole was not deep enough for the jack to come to the other end and be able to put a nut on it. I used a spade but, drilled a little, checked it, drilled some more and checked it until I liked how much the jack stuck out the other side.

I tried cutting gears, but that proved to be a pain. I might design some gears and print them out on the 3D printer at the library next time.

I made a spool to fit on the potentiometer (Pot). I have a piece of round stock in the garage. I cut a sliver and drilled a hole in the middle to slip over the pot.

I found a bracket to mount the pot too. Any "L" bracket will work. I had to drill a hole out on this bracket and notch it for the tab on the pot that keeps it from spinning in the hole.

I mounted the pot and placed the bracket where I wanted to, then screwed it in. 

pot mounted with spool

Assembled wood parts, sanded and started primer and painting.

Once I got the base coat of paint down, I started getting the components ready to be installed.

Circuit work

1. Used a multimeter to check the pot to know what will be attached to which terminal
2. Cut all the lengths of wires needed. I used different colors to help me keep it straight.
• Yellow - jack tips
• Black - jack rings
• Purple - capacitor
3.  Solder tined all the ends of the wires, jacks, pot, and capacitor. 
4. Soldered the wires to the jacks
• made sure I put the right wires on each jack. mine was easy, the shorter black and yellow to one jack and the long ones on the other jack



both jack rings to same post on pot
jacks tip, and capacitor is split between the other 2 posts

• Capacitors have a shielded side, but it does not matter much in an inclosure like this, but still I put the wire on the sided I wanted it to be on.
5. installed the jacks in the housing
6. Soldered the ends of the wires to the pot
• verified after each solder to make sure it was correct and continuity.
7. Glued the capacitor down with a dab of wood glue.

capacitor glued down

Onto the mechanical portion - the cord needs to be connected to the under side of one side of the pedal, ran through a hold in the body. looped around the pot spool, then down to the other end and connected to the other under side of the pedal.

picture of the bolt and the change of direction of the cord.

I drilled holds in the top of the base. Attached the pedal to the base, and used an awl to mark the pedal where I wanted to connect the cording. Detached the pedal, and attached the cording. On the bottom end I drilled a hole in the side of the housing and put a bolt all the way through so that the cord change direction and will be able to route a straight path to the pot.

You need a way to keep tension on the cord, but not too much. You can use a rubber band or a spring.

One of the versions of this mechanism I cut grove in the spool to keep the cording from splitting off. but I was also experimenting with different ways to attached the 2 ends off the cord. I used too much pressure and ruined that spool.

Worked on a bottom cover.

I found the cord would slip off the spool, so I sanded the center with a rotary tool. First time I did it, I took too much off, so had to make another spool again. In all I created 5 spools until I was happy with one. By sanding the center it leaves a lip on the outside that helps to keep the cord from sliding of the sides.

To see more explanation on the outside paint click here

Who knows maybe I will try making a Wah-Wah pedal sometime.