Introduction: Pedalboard With Built-In PSU

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About: I work in TV/broadcast and film, but I like to do some welding and woodworking in my "free time." Check out my blog for more camera-specific things: http://diffusedlight.wordpress.com

When I started playing bass, I thought I'd get one of those multi-effect pedals and be done with it. After a while, I realised that those are subject to the "master of none" symptom--may be able to do a bunch of effects, but none of them are exactly outstanding. So I went pedal-free for a while...but things change.

I've accumulated what I feel are probably all the pedals I'll need, and I'm tired of carrying them around loose in a bag. I'm also tired of keeping up with power adapters. I'm also looking to have a central place to hold the things I need for my musical exploits. I'm also trying to expand my horizons of materials, which is why I decided on aluminum and rivets, something I've not really worked with before.

The pedalboard design is scalable, though I wouldn't let your gaps get too wide. The structure holds together pretty well, but I wouldn't let the spaces get too much wider without adding more support. The overall design, once built, is pretty springy, so I may be adding supports later.

The power supply design is related to the specific pedals I need. Two takeaways: I haven't tested the power here for cleanliness (because I don't have any tube-based pedals), and all my pedals are DC or DC-capable. So if you've got finicky pedals, or you've got some that are AC, I don't know how to get you there. I also had to change my design half-way through because I made a couple of stupid mistakes, so I'll related to you what I did and you can hopefully make some better choices.

I'm going to build a case for it too, but that will have to be in another Instructable.

Step 1: Tools, Parts, and Pieces

Pedalboard

Materials:

  • 3x 1/16" x 1-1/2" x 96" aluminum (8' strips, I bought them at Lowe's)
  • Heavy duty Velcro (also available at Lowe's)
  • 1/8" rivets

Tools:

  • Saw for cutting aluminum (I used my miter saw for cutting wood)
  • Rivet tool
  • Tool for bending aluminum (I have a 30" brake from Harbor Freight

Power Supply

Materials:

  • 1x AT or ATX power supply (if you have an ATX, you'll have an extra step)
  • 1x 23-gauge 6" x 8" aluminum sheet (bought mine at Lowe's)
  • DC-DC buck converter(s) (dependent on your pedal power requirements)
  • 2.1mm coax female panel-mount connectors, isolated
  • 2-conductor wire (no bigger than 20-gauge)
  • 1/8" rivets (if you want to enclose the case)

Tools:

  • Side shears for cutting aluminum
  • Tool for bending aluminum (again, 30" brake, Harbor Freight)
  • Soldering equipment
  • Voltage meter

Step 2: Pedalboard Design

When I went to design this pedalboard, I wanted two things: a steeper angle than I have seen on the market, and lightweight. I thought of manipulating aluminum because I'm trying to expand my horizons beyond wood and steel, and because it would be meet at least the latter of the two requirements. I wanted the steep angle because I sometimes set my pedals on top of my amp while I'm adjusting stuff, and wanted to be able to see the values of the knobs I'm turning.

I kinda of freehanded the design. I'm a compulsive SketchUp guy, so I built all the pedals and roughed out a size I needed for the surface area, with comfortable gaps for cables. I picked 1-1/2" aluminum because I figured it would be easy to work with, but also big enough to support what I needed. Using the included human figure for scale, I basically put the angle at something I thought looked comfortable. That ended up being about 18 degrees, which puts the back height at four inches. This height is important for your power supply, if you're going to build that as well.

I also knew that I wanted to fabricate, so I figured out what the total length would be if I bent the supports around from a single piece, and then added an inch. (Well, I did this in theory--you'll notice some extra rivets in the first three, and that's because I didn't follow my own advice on the first set I cut. Measured once, cut three times...)

I'm using rivets to attach everything because it's the easiest. You could braze, but I feel like it would be more trouble than it's worth. And if you can tig weld 1/16" aluminum, please teach me how.

Step 3: Pedalboard Preparation

My overall cuts were 5x-18", and 4x-29". The 18" pieces were simple straight cuts.

The 29" cuts are easiest if you measure, mark, and drill the things you need to drill before you do your bending. (I say this from experience.) The measurements I made from one side were 4", 6", 12", and 16", then 3/4" from the other side. I drilled a 1/8" hole in the center at the 6" and 12" marks, in order to attach the board to the case later

A 90-degree bend at 4" creates the back height, and then a 90-plus degree bend at the 3/4" mark creates the tab to attach the back to. The brake from Harbor Freight has a more-than-90-degree angle on the bracing block, which is there to account for spring-back from certain metal forms, but I found that if I pulled this bar all the way back, it was enough of an angle that I could use it without bending further.

For the bend at the 16" mark (which puts 12" flat on the ground), I just bent the aluminum with my hands. Two thumbs, slow and steady pressure, to make sure you don't torque it at a funny angle. It's okay to not completely bend it back to where it needs to be for the attachment, because the rivet will hold it in place, and it also keeps some tension in the form. This provides a little bit of spring for when you really stomp on that stompbox.

If you mess up (like I did, several times) you can get creative to fix your mistakes. But it's so much easier if you take your time and do it right first (I'm speaking to my past self here.)

Step 4: Pedalboard Assembly

Once you've formed the supports and cut your cross pieces, it's time to get started. I got my distance between cross-bars from Sketchup, but in retrospect, I probably should have put #1 and #4 on first, then cut up the actual distance to keep things even.

First I marked the middle points of each cross-bar, then marked the centers of where I wanted the supports. I drilled out all four holes in each cross-bar first, numbering the bars as I went. Then I clamped #1 to the side supports, making the back of the cross-bar flush with the back of the support. Because of my mistakes, the rivets I had to use did make things a little wonky, but subsequent rivets helped.

I used a Sharpie to mark through the cross-bars, then drilled out the holes in the supports. I then riveted the #1 cross-bar to the supports. Don't worry if the supports rotate or go out-of-square at this point--getting more rivets in more cross-bars will firm it all up.

I moved on to #2, using a carpenter's square at every possible point to keep things square. I worked my way from left to right, top to bottom. I found that a piece of plywood between the sawhorses gave me a good support system for the drilling as I went further down.

Once I had all four top cross-bars on, I tried a dry fit of the pedals. Happy with that, I proceeded to put the industrial strength velcro on. The velcro is 2", so I ended up using my knife to cut the velcro such that I could fold it under. I put the hook on the board itself, the idea being that if a pedal needs to come off and go on carpet or something somewhere else, I'd rather have the loop/soft side on it.

One thing I changed last minute--you'll notice in the SketchUp plans a fifth cross bar, located at the back bottom of the supports. I cut this 18" piece, but I didn't put it on at the time. I can't remember why, but I'm glad I didn't, because my power supply might not have fit as well if I had! I will say, though, that without that cross piece, the bottoms of the supports can go left and right, and possibly bend aluminum along the way. I plan on building a case for this board, and will be attaching the lid to the bottom, which will take care of it for me, but if you're not going to build a case, having that cross piece will probably give if a lot more structure.

Step 5: Power Supply Adaptation

I happened to have an old PSU lying around, which is what sparked this idea. Some quick things before you go too much further:

  • Your pedals may have several different voltages.
  • Your pedals may have different polarities on the inputs.
  • Your pedals probably won't have a huge current draw, but they might.
  • Your pedals might actually have AC input.

In my case, I had primarily two voltages: 12v and 9v. I also had a mix of center-pin-negative and -positive pedals, and my preamp could take both AC or DC. The easiest way to figure these things out is to look at your pedal's included power supply/wall wart, although the draw of the pedal might actually be lower than the PS. And my Big Muff Pi didn't come with a wall-wart, so I had to look it up online.

The standard outputs of a computer power supply are 3.3v, 5v, and 12v, with some negatives thrown in for good measure. If you can find your particular PSU's datasheet, you should find the specific voltages and minimum loads for it. In general, though, red wires will be 5v, yellow will be 12v, and black negative. Orange is probably 3.3v.

I'm using a DC-DC buck converter from Amazon to take one of the 12v outputs down to 9v. That buck converter has a max output of 3 amps, so if you've got the high-draw pedals, something to keep in mind.

I thought long and hard about making the power supply such that it could be swapped out with another ATX if it died on a set, but I eventually made it all one piece, partially because I ran out of time, but also because I didn't take the time to find the appropriate parts and pieces. Had I gone that way, it probably would have been a simple matter of finding an enclosure deep and wide enough to have the coax jacks, and then making a tail to a four-pin IDE connector.

Once I determined how many pedals needed what voltages, I sketched out an idea on paper (which I forgot to take a picture of.) I decided to make my 9v jacks center-pin negative, and my 12v center-pin positive. I'm using two different 12v lines from the PSU to drive my two sets, but I'm going to be adding a USB output using one of the 5v lines later (for the inevitable phone or tablet charging.) I'm putting four of each flavor for now.

Step 6: Power Supply Wireup

As long as your DC jacks are isolated (i.e., not all-metal construction) you should be fine to use aluminum here too. If you're worried, you could probably make something out of PVC, or even 3D print something if you're frisky like that. I don't have a 3D printer, though.

My idea was to fold some aluminum into approximately the same size as the power supply, and then attach it to the PSU using rivets or screws, and keep the wiring "internal." When I made a major screw-up and didn't have enough sheet to correct it, I took a piece of leftover bar and folded it to cover the holes and reach back to the casing. I tapped a couple of small holes in the casing, and used some leftover screws from the case the PSU came out of to attach the extension.

If you have an ATX power supply (and you probably do) you'll have to short the "turn-on" wire in order to get it to turn on. You could add a SPST switch between the connection, which would give you an easy on/off solution, and I will probably do that in the future. You may also have to add a minimum load to the 5v line. This is sometimes optional for functionality, but approaching the minimum loads listed on your PSU's datasheet will help the PSU last longer, as they tend to keep the power stuff stable.

I just cut the cords I didn't need and taped them up. This was mostly the big 20+4-pin bunch of stuff, and I left all the IDE/SATA cables out to the side. If you're adapting this to be the PSU plus enclosure design, then you can do with it what you want. I did see this 20-pin breakout on Amazon if you want to really make it easy on yourself.

I used very small pieces of wire to daisy chain my outputs together. It was a bit of a pain to do when I had already fabricated everything, but I'm not sure how else I would do it without creating a bunch of extra wire in there. All the wire I used was 26 AWG flexible stuff from Amazon. Little bits of solder keep things hanging together.

Step 7: Install the Power Supply & Wire It All Up

The most simple step! Slide your power supply in, and affix it with your choice of adhesive. I used some of the 3M squares I used to attach my buck converter to the enclosure.

I had some trouble getting coax lines up and wired, but everything worked very well once it was up and going. I will come back through and label everything when I get to adding the USB outputs.