Guitar Pedal Building, From Zero to Rock

This instructable is particularly about building your own guitar pedal, generally abot electronics.

Step 1: Guitar Pedals

Bulding guitar pedals it's a fun activity, not to mention cheaper and more versatile, you can tweak them until you get the tone you like. Ok, let's start.

Step 2: Choosing the Schematic

The internet is full of schematics, but some of those might be wrong or might contain mistakes. So, if the schematic isn't 100% verified use your friend: the breadboard. It's a nice friend to have around, you can tweak the values of some components until you find that special tone you like. Try not to use a schematic containing components discontinued since Khrushchev and Kennedy were playing Red Alert in Cuba, lots of shematics out there with available components, also cheaper. Experiment with what you have available. The schematic chosen for this tutorial is Maxon OD808, a nice overdrive.

Step 3: Components

Before you start designing your pcb it's better to have your components ready, this way you know their exact dimmension.

Step 4: Designing Your PCB

There are many ways you can make your pcb: vero, perfboard, turrets, etc... Chose the one suitable to your skill or your available tools.

Usually i design my own pcb's, if you want to do that you have a lot of CAD tools available for free: Eagle, Express, etc...

If you decide to make your own PCB's, double and triple check the schematic after you draw it, it sucks to have your work compromised from step 1. When you are done, design the PCB. Be careful with the ground trace and other things that make your pedal annoyingly noisy.

Step 5: Transfering the PCB

In this tutorial I used glossy paper from commercials spamming my mailbox. I don't use them anymore, now I use cheap photo paper, it's much easyer to peel and the tranfer is better.

First I print the PCB on a normal paper, then, on top of it I put the paper (glossy magazine or phote) on which the design will be. This is not necesary, but I'm cheap and I don't want to waste photo or glossy paper. Take a piece of "blank" PCB and make it shine so you can see your reflection on it. Try not to put your fingers on it after that.

Place your paper on top of the PCB making sure it's on the right position. Don't put it directly on your table if you don't want any trouble with your wife/mom.

Start ironing. Don't press too hard or your wide traces will became wider. You can see the tonner sticking to the PCB, iron the board for around 3 minutes. After you're done let the board cool, this is important. If you use glossy paper soak it in water and peel the paper off. If you use photo paper soaking is not required, you just peel it off. Use a marker if necessary to enforce weak or discontinued traces.

Step 6: Etching

After you check the traces a few times it's etching time! I use Fe2Cl3, other options are also awailable.

Be careful with the Fe2Cl3, it stains stuff with a nasty orange shade.

The last picture is from another pedal (BB Preamp + Booster), i used photo paper for the transfer.

Step 7: Placing the Components

First clean the toner, for that I use very fine sand paper. Then it's drilling time!

After you drill the board you clean the traces again. I also use some resin disolved on technical alcohol for the traces. This way the soldering flux sticks muck better to the board.

Place the components. To protect the traces I cover them with flux.

Check the board: components, connections, etc...

Step 8: Testing the Board

Easyest way is with some wired jack's, you can't bypass the pedal but you can check if the pedal is working.

General rule nr.1 - if you see smoke, it's not a good sign. You did something wrong, most likely reversed the PSU polarity. Try to use a diode for protection.

General rule nr.2 - try to have only one ground wire to avoid loops.

A more elaborate testing tool is a pcb with a 3PDT switch, in/out jack's a PSU jack. You can see it on the last picture, i also use it with my breadboard.

Step 9: Preparing the Enclosure

Before you drill the enclosure mark the place where the holes will be. Check the dimmension of the switches and plugs and after that check again. Do that for about 3-6 times, you can't undo the holes once you drilled them.

Place your PCB inside and wire the switch and jack's. Test the pedal again.

Step 10: Engraving the Enclosure

First you must draw your design with a CAD. Personally, I use Inkscape.

There are many ways you can transfer your design to the enclosure. You can try the same way you make your PCB, with toner transfer. It allows you to make a more detailed design.

In this instructable i'm using a different method. This is one of the methods I use for simple designs. The advantage is that the etching is very deep but you can't make too many details with this method.

First, clean the enclosure using very fine glass paper (2000) and print your design.

Cover the enclosure with adhesive paper used in construction to protect the surfaces.

Place the design on top and using a sharp cutter cut the design. Watch your fingers with the cutter! The tip of the cutter must be wery sharp, otherwise the paper will crumble.

To etch the enclosure you can dip it face down in Fe2Cl3 or use my method involving my kid's silly putty. Don't use concentrated Fe2Cl3, I use what remains after etching pcb's (I told you I'm cheap!).

Clean the enclosure and polish it.

Drill the hole for the LED and put the pedal together.

Step 11: Done!

That's it. Now you have your very own custom pedal.

Quick demo. I'm not a guitar player, this is why it sounds crappy.