Router Fixture for Radiusing Guitar Fretboards

Unless you’ve been up close and personal with a guitar, it’s easy to miss that the fretboard (where a guitar player presses on the strings) is not flat. There is a slight curve, the amount of which varies with the type and brand of guitar. There are even guitars with fretboards that have a compound radius that changes from one end to the other.

finger board radius cutter

[Mike] is a guitar builder and needed a way to radius his own fretboards. He did what any other DIYer would, he designed and built a tool to do exactly what he needed. The fretboard radius cutting fixture consists of a new large router base that has a curved bottom. This base rests on two metal pipes and can slide both back and forth in addition to along the new base’s curve. The flat fretboard blank is secured to the fixture below the router and is slowly nibbled away at using a standard straight flute router bit. A little sanding later and [Mike] will be able to keep moving forward on his guitar builds.

Homemade 3D Carving Duplicator

[Frank] is a guitar builder and has to make a quantity of acoustic guitar bridges that wouldn’t make sense to do manually by hand each time. He wanted a way of duplicating bridges quickly and precisely but he didn’t want to go to a CNC machine. Instead, he build a 3D duplicating machine.

The machine has 3 perpendicular axes, just like a milling machine. Mounted to the Z Axis is an air powered spindle that can reach 40,000 RPM. All 3 axes are moved by the operators hands. Normally, free-hand cutting something like this would be very difficult. [Frank’s] solved this in his machine by using a stylus that is offset from the cutting bit. The stylus is the same effective length and diameter of the cutting bit and is guided over a finished bridge pattern. While the stylus is tracing the pattern, the spindle and bit are removing material from a bridge blank. The stylus is continually moved over the entire pattern bridge until the spindle is finished carving out a new bridge out of the blank.

To aid in lifting the heavy Z Axis and spindle, [Frank] added a counter balance to make tracing the pattern extremely easy. Once the new bridge is carved, it only requires minor sanding to remove the tool marks before being installed on a guitar! [Frank] admits his linear bearings and rails are very rigid but also very expensive. If you’re interested in a less-expensive 3D duplicator, check out this project.

Guitar Speaker Cabinet Actually Belongs In Garbage Can

[Dano] builds a lot of guitar pedals and amps. He needed a speaker cabinet dedicated to this task in order to be a consistent reference when checking out his electronic creations. He ordered a couple of 10″ guitar speakers…. and they sat around for a while.

Then one day at the craft store, he stumbled on an inexpensive wooden trash can. It had a tapered design and came with a lid. As would any normal person, [Dano] immediately thought these would make a perfect speaker cabinet so he bought two of them.

The trash cans would be used in an upside-down orientation. The intended lid makes for a well fitting bottom of the cabinet. Holes were cut for the speaker and two terminal blocks. Since these cabinets would be used for testing a bunch of different amps, two different terminal blocks were used to permanently have multiple connector types available.

A pair of modern kitchen cabinet handles were used as carrying handles for each of the two cabinets. If a speaker cabinet one speaker tall is cool, a cabinet two speakers tall must be twice as cool. To get there, the two cabinets were bolted together using electrical conduit as an industrial looking spacer. Those brackets bolted to the sides of the bottom cabinet are actually Ikea shelf brackets that [Dano] had bought and never used. The Ikea brackets support casters making for easy moving around the studio.

Overall, [Dano] is happy with how his cabinets sound. They are very unique and interesting at the least. We’d be happy to play some riffs through them!

Wireless Mic Helps Guitarist Rock Out Un-Tethered

Any guitarist knows what a tangled mess of cords can come out of a long jam session. One possible solution would be to get a wireless guitar system, however, such a setup can range in price from about 50 to several hundred dollars. That’s a big price to pay for not having to untangle some guitar cords.

[mattthegamer463] wanted a wireless setup but didn’t want to spend the cash on one. He’s a tinkerer and had a spare wireless microphone setup hanging around. So, he decided to try converting the wireless mic to work with his guitar.

Both microphones and guitar pickups work in similar manner. In a guitar pickup, the vibrating guitar string disturbs a magnetic field and induces a current in the pickup’s coil. That current is the guitar’s signal. Microphones are similar, air pressure waves vibrate a diaphragm or ribbon which then disturbs a magnetic field to create the signal. [mattthegamer463]  thought these principles were close enough for him to make quick work of the conversion.

First, the microphone was taken apart and the diaphragm module was removed, cutting the two wires that ran into the mic’s handle. A hole was then drilled into the wind screen so a 1/4″ jack could be installed. [mattthegamer463] states that it’s important to electrically isolate the jack from the wind screen or the signal and ground wires will short and the project won’t work. The two wires that were previously connected to the diaphragm module are then soldered to the newly added jack and the mic was screwed back together.

To use it, a patch cord is run from the guitar into the jack on the mic. The stock wireless receiver from the mic system is then plugged into the guitar amp. The modified ‘mic’ now transmits the guitar signals to the guitar amp! You may think it would be awkward to hold that mic while jamming. You’d be right if [mattthegamer463] didn’t come up with a nice looking aluminum and rubber belt clip.

3D Printed LED Guitar Chord Chart

Learning to play guitar can involve a lot of memorization – chords, scales, arpeggios, you name it. [MushfiqM] has made the process a bit easier with his Digital Chord Chart. Just about every beginning guitarist keeps a chord app, chord book, or even a chord poster handy. Usually these chord charts are in the form of tablature, which is a shorthand method of showing where each finger should go on the instrument. [MushfiqM] took things a step further by actually placing that chart on a 3D printed model of a guitar fretboard.

ledmatrixx[MushfiqM] started by rendering a 3D model of an abbreviated guitar using Autodesk Inventor. He then printed his creation in 3 parts: headstock, neck, and fretboard. The neck of the guitar was hollowed out to allow room for a matrix of LEDs which would show the finger positions. [MushfiqM] then painstakingly soldered in a charlieplexed matrix of 30 leds, all connected by magnet wire. The LEDs are controlled by an Arduino UNO, which has the chord and scale charts stored in flash.

For a user interface, [MushfiqM] used a 2×16 character based LCD and a low-cost IR remote control. All the user has to do is select a chord or scale, and it’s displayed on the fretboard.

There are a couple of commercial products out there which perform a similar function, most notably the Fretlight guitar. Those can get a bit pricy though – costing up to $400.00 USD for an LED enabled guitar.

[via Instructables]

Guitar Mute Pedal Made From Upcycled Parts

Rockin’ out on your fave guitar is pretty fun for sure but whether your on stage or jamming in your basement, it can be convenient to quickly mute those killer licks. [wozlaser] wanted a mute pedal for his guitar and instead of shelling out the tens of dollars for a commercial version, he decided to build one himself.

This pedal is heavy-duty and made out of metal. If the frame looks familiar, that is because in a prior life this was a control pedal for a sewing machine. [wozlaser] found it cheap at a thrift store. After the internals were taken out, he added a few key parts. First were the 1/4″ input and output jacks that were scavenged from an old stereo system. There is a momentary switch from a VCR and a standard guitar stomp pedal switch mounted all the way in the front of the frame. The wiring is as follows:

DIY guitar mute pedal

The wiring schematic is pretty darn simple, it just grounds and ungrounds the signal wire. As stated earlier, there are 2 switches, a momentary and a push-on/push-off switch. A normal mute pedal would only have one switch but [wozlaser] wanted something special. If you push the pedal all the way forward it will mute or unmute the signal until it is pushed again. When the pedal is in the spring-supported ‘up’ position a lever pushes on the momentary switch, a slight push on the pedal lifts the lever off of the momentary switch to mute or unmute the signal. The function of the momentary switch (mute or unmute) changes with the state of the other switch. This works exactly the same as a 3-way light switch circuit allows two switches to control one light in your house. With this setup [wozlaser] is able to not only mute and unmute his guitar but strum a chord with it off and pulse the chord on to the beat of the music or tap the pedal with some guitar feedback to make the sound cut in and out. All that only cost [wozlaser] a little time and spare parts… and there are no batteries to replace!

Guitar Pedal Hack via Manufacturer’s Shortcut

There seems to be no shortage of manufacturers that cut costs by using similar components across a wide range of products. This isn’t necessarily a bad thing though, since it makes it easier for someone with some know-how to quickly open up the product and figure out how to get more use out of it. [Lewin] noticed some peculiarities on the PCB of his EHX Screaming Bird guitar pedal, and used a manufacturer’s shortcut to turn this treble-boosting pedal into a flat booster.

Once [Lewin] removed the case, he noticed that there were some unpopulated pads on the PCB. Additionally, the potentiometer was labelled as 10k, but a 100k was actually installed. These were indications that something was awry, so after poking around on the internet, [Lewin] now believes that the same PCB was used to make at least three different effects pedals with similar internal structures.

The Screaming Bird pedal was a little harsh for [Lewin]’s taste, so he changed out some capacitors on the board to get it closer to the flat booster. There are some other things that could be changed, but now he has a pedal that suits his needs much more appropriately, thanks to the manufacturer making only minor changes across a range of similar products. Historically, guitar pedals are pretty easy to modify, but it’s nice that the manufacturer of these has made it so much simpler!