Introduction: 3 Guitars Made From a Table. #2 the Cybar Box Guitar
I wanted to make an electric bass guitar using hard wood.
Wood that has been drying long enough not to twist anymore.
A whole-wood table plate sounded perfect for this.
I found an old one, made of birch, for free on the internet, I only had to fetch it and say thank you. Brilliant.
It turned out this gave me material enough to make 3 guitars.
This is the second one, a cigar box guitar, with some visible computer parts, hence the name.
The cigar box also came free of the internet, friendly people never stop to surprise!
Cigar box 0$
Pickup: No brand Rosewood Humbucker 29$
Piezo pickup: No brand 27mm brass 1$
Sound holes: Astons music shiny brass grommets 7$
Potentiometers: 2 x 1M logarithmic and 1 500k linear 2$
1/4" jack: No brand 1$
3-way switch: Tele/stratocaster clone 3$
Bridge and nut: Heat sinks 0$
Strings: Alice plated steel electric light tension 4$
Tuners: LesPaul clone 8$
2 discarded hard discs 0$
Assorted springs for acoustic reverb effect 2$
Aluminum foil: regular household version
Step 1: The Neck Construction
I thought I would try to make a scarf joint for the guitar head.
A scarf joint is made by cutting a piece of wood at angle, and turning one of the pieces 180 degrees and joining them together again.
One of the pieces will now have the same angle to the other as the angle of the cut.
This makes a strong joint.
The neck is two pieces of wood glued together, and I first glued the head to the lower neck piece at an angle.
After sanding the result as flush as I could, I then glued the top piece onto the bottom piece, now containing the head piece at an angle.
Step 2: Neck Shaping
Since the neck was straight, I used the opportunity to make slots for the frets that would be mounted later.
It is easier to get the 90 degree angle straight when the neck is straight.
The neck was now both wider and thicker than it should be, so I could start removing material.
I wanted a neck width of 40mm, an thickness of 27 mm and a string spacing of 13 mm.
Step 3: Fitting the Neck to the Box
I got a small cigar box, so I had to plan the content well.
The neck is normally in the center of the box, but it does not have to be centered.
The content I wanted in the box was:
- A humbucker pickup
- A piezo pickup
- A 3-way switch to select between the pickups or have them both play simultaneously
- A volume potentiometer for each pickup
- A tone potentiometer
- A 1/4" jack
- Some sound holes
- Springs for acoustic effect
I wanted the neck to go through the whole box and rest on the back wall, to make it as solid as possible.
I wanted the neck and fretboard to go a bit into the box, so I had to carefully remove material from the box.
I was lucky to get a quite solid cigar box, so I made the opening just a little tight, and filed little by little until it got a snug fit.
The neck was then glued to the bottom of the box.
Step 4: String Attachment
The bridge I planned to use was a large heatsink from a computer motherboard.
It slightly dictated the position of the strings.
I could let them go through the box, making the string ends invisible from the front side.
Pop rivets are perfect for a solid string seat, after removing the rivet itself.
I drilled 3 holes for the strings through the box with the neck in its intended position inside the box.
The pop rivet seats were hammered in from the bottom of the box.
The plan was to do the same on the top side of the box after the final assembly, but that was forgotten.
Step 5: Frets
The fret slots were already cut, so I could now insert the frets.
I do not have a fret press, but using a small fret hammer worked quite well.
The neck is quite straight, and the string tension is not large on these 3 thin strings, so there was no need for any fretwork, just snip off the excess ends and file them round so you don't cut yourself on the fingers playing.
Step 6: Control Electronics
The top and bottom of the box was separated to be able to comfortably work on them independently.
I installed the jack and potentiometers in a row, to be able to fit the 3-way switch next to them.
I found 22 uF capacitor and added it to a 500k ohm linear potentiometer for the tone control.
I do not hear much difference when turning it, so the values of the resistor and the capacitor might be all wrong.
I have not found any good guidelines for these values, but then again, the problem could be my ears.
The volume potentiometers are 1M ohm logarithmic.
Step 7: Pickups
To install the humbucker pickup, I broke the end of a small hack saw blade to cut a square hole in the box lid.
I drilled holes for 3 sound holes, expanding them with a tiny round file until the sound holes fit the holes snuggly.
Directly below the bridges contact point with the box, I hot-glued a piezo in place.
First a big blob of glue, pressing the piezo into it, covering it with more hot glue and adding a piece of plastic on top. Pressing down on it with something flat and heavy, made the piezo all encapsulated with hot glue.
The pickups wires were soldered to the 3-way switch and the volume potentiometers according to a schematic shown on the next page.
The soldering is ugly, but it works.
Note the ground wire that is screwed to the side of the box, this is added to ground the shielding of the box.
Step 8: Bottom Box Finish
The neck needs a groove to give room for the humbucker pickup, so I cut away some material.
I glued aluminum foil to as much of the box I could reach, to eliminate as much noise as I can.
I covered it with electrical tape where it is close to the humbucker, and also covered the potentiometers and switch from accidental grounding.
Then I could glue the box shut.
I added a couple of hard disks to the back of the box, since this is a Cybar box guitar, and I needed to cover a hole where the 3-way switch turned out to need a bit more room after my soldering added to its thickness.
This is what they look like inside the enclosure, if you ever wondered what a hard disk really looks like.
Very shiny discs.
The hand drawn schematic shows how I wired the controls.
An effect of this is that when you play with only one pickup, the volume of the other cannot be turned all the way down, then all the sound mutes.
Not a problem, but someone with a better understanding of electronics could probably wire this in a better way.
Step 9: Nut and Bridge
These both came from the same computer motherboard, large heatsinks cooling some of the larger and warmer circuits.
They have 6 slots, which did not add up to my 3 strings, so I drilled holes in the middle of both to get the desired string spacing.
The bridge still has half of two of my drill bits inside it, so the mid string exits slightly off center in the back, and even a little it in the front.
If they turn out to be in the way when playing, sharp edges as they have, I will replace them with more normal cigar box items, like a large key or nuts and bolts.
I really need to wind more of the string on each tuner, this will not hold the tuning for long.