How you can you build a pickup for an electric guitar using neodymium magnets and some wire? Musicians and engineers want to know! Building one ourselves seemed like a great way to learn about what's involved and how one can be made rather easily.
Our pickup is a simple, easy pickup you can make with simple materials. You could write a whole doctoral dissertation on this subject, what materials work best, what kind of magnets produce the best sound, how many turns of the wire, etc. Since audio engineering is out of our realm of expertise, we stuck to a simple design...and it worked great!
Tools needed: Soldering iron, knife, wire cutters, screwdriver, turning device (we used the spindle of a sewing machine).
Step 1: Find an Old Guitar and Remove a Pickup
We took an old guitar and removed one of the pickups from it. This involved removing the guitar strings, unscrewing the pickup screws, and cutting the wires that connect to the pickup.
There should be two wires to cut, black=hot, white=neutral. Green=ground, the ground does not need to be cut!
We cut the wires that connected to the humbucker, which is shown in the third picture. This made it easier to solder the wires on the pickup we created.
Step 2: Take Pickup Apart and Trace
To make sure we had an exactly sized pickup, we took apart the pickup from the guitar and traced it. We used thin wood that you can find at any craft store. We also tried plastic, which was a bit more tricky to work with, but could also work.
We designed our pickup with simplicity in mind. As you can see from the original pickup, there are two ceramic magnets at the bottom of the pickup, which magnetize 6 individual steel rods. These rods are aligned with each string on the guitar to pickup the vibration of the string.
We decided to make it quick and simple, and will basically have a small reel of wire with one magnet on top. Ceramic magnets are much weaker than neodymium. Using neodymium magnets instead of ceramic means we can use a smaller magnet to get the same magnetic field.
Step 3: Cut Out Shape and Glue
After tracing the shape of the old pickup, we cut out the pieces and glued them together. There is a top, bottom, and middle piece. Stack them together for form a wooden spool for the wire to wrap around. Glue the pieces together. Once the glue has dried, the piece is now ready to be wound with wire!
Notice the two holes in the bottom piece. These will be for the screws to screw the pickup into the guitar. We figured we would make the holes at this step so if we messed up, it wasn't a total loss.
Step 4: Winding the Wire!!
Now it's time for the most crucial and hardest part of the process...winding the wire! We used 42 gauge magnet wire, like this product here. Thin wire is commonly used for pickups, typically 42, 43, or 44 gauge is used. The 4th picture above shows the magnet wire next to some human hair under a microscope...that's how thin it is!!
Because it is so thin, it is very hard to wind. We tried many methods, including a cordless drill and a drill press, with various fixtures to hold everything in place. The best option we found was to use the spindle of a sewing machine!
We taped the pickup onto the end of the sewing machine spindle, had the spool of wire setup, ran the wire through a tension wheel and to the pickup. The sewing machine had a foot pedal, which we could start slow and go faster when needed. We found that it needs to start slow, or else the wire will break right away.
Make sure to leave some wire hanging out in the beginning, as this will be soldered later on in the process.
Step 5: Counting the Turns
We wanted some automated way of counting the turns of wire. Naturally, we used magnets to solve the problem. We attached a single D68PC-RB red and black cylinder magnet to the spindle of the sewing machine. The magnet spins with the wheel.
We then placed a stationary reed switch to the body of a machine. A reed switch is a simple, inexpensive sensor that closes the switch when a magnetic field gets close. The switch closes every time the magnet passes by, once every turn.
We then took an old calculator apart, and wire the reed switch to the PLUS button on the calculator. After we soldered the two wires to the contacts of the PLUS button, the calculator now interprets the closing reed switch as a hit on the PLUS key. Every time the magnet goes by, the calculator acts as if you hit the PLUS key. Simple and effective.
Step 6: Winding the Wire...still!
Once the winding setup was finally complete, it is time to wind the wire. This is a very tedious process. Again, you have to be VERY careful handling this thin wire. It broke on us many times. While it is winding, you have to guide the wire back and forth over the width of the pickup, to spread the wire out evenly. This can be seen a bit in the video.
We almost hit 7,400 turns and boom...the wire broke. This was enough turns for us! From our research, we found that anywhere from 6,000-8,000 turns is pretty standard.
Step 7: Preparing the Hookup for Installation
Once you have the desired amount of turns, you can remove the pickup from the sewing machine. We cut a little notch in the wood to hold the wire in place using tape. Leaving some of the magnet wire out, we scraped off the thin layer of insulation on the wire.
We then soldered the thin wire to some thicker, more insulated wire. This makes installation a little bit easier. You should have two ends of the thin wire to solder to, one end that was left out in the beginning and one end after the winding is finished. This will insure the current travels through the pickup!
Soldering this small wire was tough. It had to be done very carefully, but eventually we got it!
Step 8: Preparing the Wire for Installation
This is what our final pickup looks like! Two wires coming out of the pickup, which will be soldered back into the guitar circuit. We placed a long, thin BY041 block magnet on top of the pickup. This small magnet will easily pickup the vibrations in the string and produce some decent sound!
Step 9: Install the Pickup
The pickup is soldered back to the humbucker where you originally cut the wires. Once soldered, the pickup can be fastened to the guitar using the original screws.
Step 10: Restring the Guitar and Test!
Here is the final step! Restring the guitar, tune it up and start playing! Here are some pictures of the final product after installation and a video of some testing. We think it sounds pretty darn good!
Stuff we skipped, which most people don't skip:
This is a quick and dirty pickup to show that anyone can do it. While easy, this pickup isn't something you'd want to install before your next gig. When we tap the magnet with our finger, it produces a thunk, like when you tap a microphone. Professional pickups don't do this.
Why does it do this? After winding the wire, pickups are normally dipped in hot wax. This helps hold it together and prevent vibration within the individual coil of wires. We also didn't secure the magnet very well. While using tape held it in place, the extremely sensitive pickup recognizes the ever so slight movement that happens when we tap it.
As previously stated, someone could write their doctoral dissertation on this subject...there is just so much here. We wish we could have made 20 different pickups out of different materials, using different magnets, change the number of windings, etc, but we just don't have time.
Thanks for reading! For even more technical information, check out this article.