Introduction: Electric Tenor Guitar
Evolution has made it so that we are able to close our eyes but not our ears. Consequently, my ears are always perked and on the prowl for new sounds. Often the instruments that produce the sounds I’m after aren’t widely available for purchase (a consequence of having increasingly eccentric taste ) or simply don’t exist. This has led me to build specialized instruments to temporarily fill the perpetual voids.
This is a glimpse into building an instrument from scratch. A process which embraces mistakes and promotes experimentation. It is also an inherently pleasurable and rewarding process that you absolutely won’t regret, should you decide to start building your own instrument!
So…what kind of guitar did I build exactly? To be honest, I’m not even quite sure if it can be classified as a guitar. Technically, as the fret spacing is diatonic instead of chromatic, it most closely resembles a dulcimer, but with an added blue note fret. It also only has four strings, like a tenor guitar and is of a similar scale length (yet still quite a bit shorter ). It's also tuned in fifths like a cello, CGDA. I understand that this hybrid instrument has a very niche audience, but the methods used throughout this build can be directly applied to a traditional guitar, bass, ukulele, etc.
Although the instrument itself is a bit bizarre and specialized, I decided to lean more towards creating a step by step tutorial rather than a show and tell, to demystify the different processes that often intimidate would-be luthiers.
That being said, let’s rock on!
Start by gathering some stock for the neck and body. If you’ve done any preliminary research, you’ve surely discovered that this is an overly debated and subjective subject, that can be boiled down to: it simultaneously does and doesn’t matter.
Honestly, there are many factors that will influence the tone and sustain of your instrument, including choice of wood or composite material, but the use of electromagnetic pickups arguably reduces this influence. Electromagnetic pickups, whether single coil or humbucking, depend on the string’s vibrations to interrupt the magnetic field to create an output signal. So, use what you have access to, whether it be pallet wood or book-matched, exhibition grade pieces of quilted Honduran mahogany from The Tree, as it’s the strings we’re amplifying.
The density of the wood or composite material you choose, however, and how tightly the neck fits to the body, will influence the sustain of the instrument.
For the body of my instrument, I used an 8/4 S2S slab of black walnut that I had squirreled away and a 4/4 S2S piece of hard maple for the neck. Again, use what you have for the neck and body and if nothing you have is big enough, simply glue up a slab from scraps!
You’ll also need some specialty guitar bits which can either be purchased online (my recommendation is StewMac) or salvaged from a cheap/broken donor guitar.
These bits include:
- Fret wire
- A bridge
- Electromagnetic pickup(s)
- ¼’’ audio jack
- 500K potentiometer
- Tuning machines (tuners)
- Strap pins (optional)
As for tools, you can easily get by with basic woodworking hand tools with additional specialty tools such as a router. Here’s a list of what I used which is by no means exhaustive or mandatory; consider borrowing, renting or finding alternative solutions for tools you don’t have. Also included in this list are the additional materials that are required.
- Hand saw
- No.1 and No. 2 Philips screwdrivers
- Flush cut pliers
- Table saw
- Mitre saw
- Coping saw or fretting saw
- Carving knife
- Razor blades
- Sanding blocks 120/220
- Sandpaper 100-320
- Powered sanders
- Band saw
- Measuring implements
- Long steel ruler
- Angle grinder with a cutoff wheel
Small triangle file, small flat file, small round file
- Masking tape
- Marking implements
- Steel rivets
- Nut material (I used elk horn)
- CA glue
Step 1: Getting Started
Before we begin…
If you’ve ever discouraged yourself from attempting a similar project, just remember that you can never finish what you never start and that starting is the hardest part. Proper luthiers might scoff at the abominations that we create and some of the processes might intimidate or terrify us (like building a neck from scratch ) but don’t let this dissuade or paralyze you. Remember that the absolute worst thing that can happen is that you end up creating an opportunity for yourself to repeat a process and improve. If you’re wary of wasting materials, take out your first attempts on laminated scraps.
Don’t overlook the potential of powerful CAD based design tools during the design process as a means of designing without the risk of wasting any physical materials. When you have a design you’re pleased with, prototype and mock it up using cardboard or card stock and tape to get a feel for its shape in a tangible way. Dive in head-first, there’s no shallow-end when it comes to projects like this. Also, do research, but don’t let it serve as a procrastination tool or let the overwhelming amount of available information bog you down. Grant yourself the luxuries of experimentation and failure.
Step 2: The Neck 1.1
Don’t let the neck strangle you, strangle the neck. The neck seems to be THE thing that not only intimidates, but instills fear in the wannabe weekend luthier. That’s why we’ll tackle it before anything else!
Use whatever means necessary to make the board you’ll be using for the neck as flat as possible. Whether you choose to laminate an additional fretboard onto the neck or install a truss rod, doesn’t really make a difference, just start with these simple steps.
First, observe the growth rings on the board's end grain. The growth rings should point towards the top of what will be the fingerboard, like a smile. Next, find the center of your board and draw a center line down the entirety of its length, that wraps around the board and continues down the center of the back of the board. This allows you to get things started before having to make real decisions.
Now onto real decisions. Start by determining a scale length (this is a measurement taken from the fretboard side of the nut to the twelfth fret, that is then doubled ). This is more arbitrary than you might think. Start by doing some research into the average scale lengths of the type of instrument you’re building. You’ll most likely come up with numbers such as, 19, 21, 22, and 24.
The scale length I decided on is quite stout compared to most guitars, including tenor guitars. Regardless of the scale length that you choose, the following steps still apply. Choose a reasonable place within the top tier of your board to position your nut, use a square to draw a line perpendicular to the center line to indicate its position.
Next, navigate over to StewMac’s Fret Position Calculator, and input your chosen scale length, as well as, the number of frets your after. This will give you all the required measurements for each fret position. To ensure an accurate scale layout, be sure to take all your fret position measurements from the nut instead of measuring from fret to fret to avoid compound error.
Once you have the nut and fret positions laid out, establish a width for the neck at the nut and a width for neck at its base (or heel). These two measurements can also be found readily online. Base your measurements on the listed averages. Next, draw lines that connect the width of the neck at the nut and its base.
While the neck is still square (generally a good idea, especially if this is your first rodeo ) cut in the fret slots with a hand saw that has a thin kerf, preferably one with a rigid back. The only saw that I could find that had the right kerf width was a coping saw, so I took care to make the cuts straight. This cutting-in of the frets isn’t a full depth cut, it’s just enough to mark out their placement on the neck. If you plan on laminating a separate fretboard to the neck, transfer the lines from the neck to the fingerboard and cut in the frets. Cutting-in the frets also allows you to retain the fret positions after adding a radius to the fretboard. Take the opportunity during this repetitive step to start thinking about headstock design.
Step 3: The Neck 1.2
Following the specs on the tuning machines (tuners) you’ll be using, layout potential configurations on a piece of paper or cardstock. Once you are pleased with the spacing and layout of the tuners, transfer their placement onto the neck board above the nut, centering them on the center line of the neck. After laying out the placement of the tuners, use an awl to mark the center of the holes.
Now you can start designing the shape of the headstock itself, making sure to leave enough meat around the tuner holes. You can model the design of your headstock off a traditional one or come up with your own design! To visualize material removal when designing, I use masking tape to tape off the areas that will be removed.
Alright, now that everything is laid out, begin shaping the neck by cutting out the extra material along the length of the neck. Use a bandsaw, jigsaw, scroll saw, or handsaw to accomplish this. This step can be skipped for now as I often choose to leave the headstock square to make it easier to clamp it into the vise while continuing to shape the neck.
Step 4: The Neck 1.3
Neck profile is a personal preference and understanding those preferences usually requires a bit of experimentation and experience by playing different instruments. If possible, a trip to a local music store allows you to study the profiles of the necks of the instruments you find most comfortable. Alternatively, you can base the neck profile off one of your own instruments. From experience, fat v-shaped necks, like the ones found on vintage resonator and parlor guitars are most comfortable for me, especially on instruments with smaller necks.
Clamp the headstock in a vise or clamp it to the top of a work surface so that the neck protrudes towards you. Ready?
Different tools can be used to shape the neck. Most commonly, rasps are used to achieve a rough shape that is later refined with files and sandpaper. The most enjoyable method, however, is to exploit the often overlooked spokeshave, from bulk material removal right down to final profile refining. Always opt for creating shavings over sawdust.
Bearing in mind that the profile of the neck is symmetrical, start either by removing material from only one side of the neck and then mirror the shape or slowly remove material from both extremities, working your way toward the center line. It is imperative to continuously check the profile of the neck by seeing how it feels in your hand as you continue to remove material.
Once you are pleased with the rough shape of the neck, start refining the shape with sanding blocks and fine grit sandpaper. Use your sense of touch to find any bumps or divots to sand out. These are imperfections that you will never be able to see, only feel. Run your fingertips over the neck to find them and sort them out. The final neck profile should feel comfortable.
Step 5: The Neck (Headstock) 1.4
We can now drill the holes for the tuners that were laid out earlier with your awl. If you have access to a drill press you can use it to drill the tuner holes, ensuring that they are perfectly straight. If you don’t have a drill press, drill these holes by hand, as straight as possible by using a square as a guide if necessary.
Once the tuner holes are drilled into the headstock, most of its thickness must be reduced to create the correct string angle from the nut to the tuners. This is simpler to achieve before cutting out the headstock’s profile but can be done afterwards.
To mark out the material to be removed, I first hot glued a sharpened carpenter’s pencil to a scrap of plywood, I then made sure that both the headstock and the pencil setup was flat against the bench before using it to mark each edge of the headstock at a consistent height. Once the headstock was marked, I proceeded to cut it to thickness with a handsaw.
Now that the headstock is the right thickness and is cut to rough shape, start to transition the front and the back of the headstock to the neck using either a rasp and files or a sharp knife. Sand the transitions to make them seamless. Continue to refine the shape of your headstock until you achieve the shape that you’re after. I decided to add facets to my headstock by using rasps and files.
Step 6: The Neck (the Nut) 1.5
To create the slot for the nut I used the depth gage on my mitre saw to cut the slot at a consistent depth. I then wrapped a piece of sandpaper around a thin piece of plywood to sand the bottom of the slot flat.
The material used to create the nut of the instrument is also a highly debated subject. There are many options ranging from plastic to ivory. I opted for elk antler. Why? I collect them from our dog once the pieces are gnawed to choking hazard size, and tone-wise it is excellent. It does, however, like most natural materials (such as bone and leather ) smell putrid once burned by friction (by power sanding it ) and once it becomes airborne dust. Wear a mask, open a window, and work in a well-ventilated area.
Whittle the nut material down to the thickness of the nut slot and cut it to about the width of the neck at the nut. Continue to refine the shape of the nut by sanding it against a flat surface. Round over the back side of the nut (side that faces the tuners ) at an angle parallel to that of the strings. Match the radius of the fretboard (if it has a radius ) by placing a piece of sandpaper directly onto the fingerboard to translate the radius of the fingerboard to the bottom of the nut. Next, use a ruler and pencil to mark the string spacing on the nut (in fact, string spacing rulers exists and can be sourced online ).
Once the string spacing has been laid out, fit the nut to the neck. The use of a couple drops of CA glue to keep the nut from moving side to side is optional. Now that the nut has been installed, use a small triangular file to create shallow grooves that will accept the strings. Deepen these grooves until the string sits below the top of the nut. Be sure to angle the string slots toward the headstock. You will refine the nut once the instrument is fully strung up.
Step 7: The Neck (Don't Fret Frets) 1.6
To install the fret wire, we must first cut the fret slots to the correct depth. Next, if your fretboard has a radius you will need to bend the fret wire to match the radius of the fret board. If your fretboard has little to no radius, like mine, you can start by cutting over-sized lengths of fret wire. Next, either press or hammer the fret wire into the slots, making sure that the crown of the fret wire is sitting flush against the fretboard. Once installed, the fret wire must be trimmed. To do this, there are specialty flush cutting pliers, however, you can create your own version by grinding the face of regular side cutters to their cutting edge. Then, line up the face of the side cutters to the edge of the neck and trim the proud ends of the fret wire. Be sure to either cover the end of the pliers with your hands or add a magnet to the end of the pliers to catch the loose fret wire ends. Wearing eye protection should also be a given.
Next, prep the neck for fret work by protecting it with tape. Then flush up the ends of the frets and bevel them, then level them, and finally crown and polish them. I will not be covering these processes at length here as they are a part of basic string instrument maintenance, but there are plenty of fret dressing resources online.
Last thing to do is remove the protective tape and install the tuners!
Step 8: The Body (Neck Pocket)
The next step is to rout out the neck pocket or cavity into the body while it is still square. This is another one of those intimidating steps that makes even experienced luthiers a little nervous. First thing’s first, measure and mark out a center line on the body. This will allow you to perfectly line up the neck with the body.
Before proceeding, remind yourself that completing the neck is an impressive feat in and of itself, and that the rest of the build pales in comparison. That said, this next step isn’t forgiving.
Begin by lining up the center line of the neck with the center line of the body. Next, clamp a straight edge to both to keep them aligned. Then, carefully trace around the heel of the neck onto the body, taking extra care to ensure that both pieces remain aligned. Once the shape of the heel has been transferred to the body, begin to rout out the neck pocket in shallow passes with a router. Be sure to stay well inside the line that was traced around the neck. Continue to rout out the pocket until the desired depth is achieved. To make hogging out the neck pocket a little easier, use a forstner bit to remove the bulk of the material before routing. This is also a way of getting around using a router if you have no access to one. Finish the pocket by hand with sharp chisels, carefully sneaking up on the perfect fit. The tighter the fit, the better the sustain!
Step 9: The Body (Shaping)
Now that the neck pocket is routed, we can start shaping the body without a care in the world! I chose a faceted geometric and asymmetrical design that reflects the aesthetics of my practice, but you can model your body off a traditional style, such as a Telecaster, Stratocaster, Les Paul, etc.
To design the shape, I used masking tape to mask off areas to be removed, this helped me visualize and refine the shape. I then traced along the masking tape, transferring the cut lines to the body blank. Once the tape was removed, I extended the cut lines to edges of the body blank to ensure straight cuts with the hand saw. Once the odd shape was cut out, I decided to add facets to the body by running it through the table saw with the blade set to various angles between 20 and 45 degrees. Wasn't as dangerous as it might appear in the photographs, I received no kickback, the body remained stable the entire time, there was no risk of the cut offs getting wedged between the blade and the fence, and my hands were well away from the blade at all times. Stay safe and only make cuts that you're comfortable with! I then proceeded to sand the body with a powered sander, to knock off the raised grain and make the surfaces smooth. I then glued a piece of adhesive backed sandpaper to a plywood off-cut to ensure that I wouldn’t round over any of the facets unintentionally during sanding.
Step 10: The Bridge
Now that the body is shaped and sanded, let’s turn our attention to the bridge. There are many bridge options, again, like most things on a stringed instrument, it comes down to personal preference. I prefer a hard-tail bridge with adjustable saddles, so I opted to modify a bridge ripped off a cheap Strat knock-off.
To begin, I removed the saddles, then lopped off two of the six string holes, as well as, the whammy bar hole by using a cut off wheel in an angle grinder. This turned a six-string bridge into a four-string bridge. I then filed and sanded the edges of the bridge until it became symmetrical and rounded off the sharp corners.
Then, I covered the body with masking tape and temporarily fixed the neck to the body to measure and mark out the bridge placement (this is your scale length measurement from earlier ). Once I had the bridge placement measurement, I proceeded to layout the bridge, taking care to center it along a redrawn center line. Next, I pre-drilled the holes to install the bridge to the body and proceeded to install the bridge.
Step 11: The Bridge (Continued)
Now that the bridge is installed, we can drill the through-holes for the strings. Using a drill press for this step is recommended, but again, it can be done by hand. Use the holes on the bridge as a guide to mark the placement of the holes to be drilled and drill the holes as straight as possible. On the back of the body, enlarge the holes slightly at a depth that will accommodate the ball end of a guitar string. To make my own ferrules or string inserts, I pounded the center pins out of steel rivets and glued them into the string holes.
Things are coming together, in fact, we’re in the home stretch! Onto amplification!
Step 12: Amplification
To amplify my instrument, I settled on using a single single-coil pickup that I modified to be a four-string pickup. To turn the six-string pickup into a four-string pickup, I removed the magnet on the back of the pickup and used a punch and a hammer to knock out the two outer poles. This was a quick and simple solution that had no adverse effect on the pickup. As a design choice, I wanted only the poles of the pickup to be visible. To achieve this, I started by using the pickup cover as a layout tool to mark out the holes for the pole pieces, then I drilled the four holes through the body.
I then flipped the body over, covered it in masking tape and started to plan out a pickup cavity around the holes. I designed the cavity to accommodate not only the pickup, but also to house the volume pot and ¼’’ jack. Once I settled on a shape, I started hogging out material with forstner bits of various diameters. I then routed out the rest of the cavity as deep as my router would allow, unfortunately the pickup needed to sit deeper to be close enough to the strings. The solution was to hog out the extra depth with a forstner bit and clean up the edges with a chisel. I cleaned up all of the edges of the cavity with chisels to create square corners, to match the overall aesthetic of the body.
To avoid making the body too thin where the pickup sat, I extended the pole pieces of the pickup by insetting the pole pieces deeper into the pickup with a punch and hammer, so that they would protrude further out from the pickup and added additional pole pieces into the newly created recesses. I continuously checked the depth and height of the pole pieces with a pair of calipers. I then inserted the protruding ends of the pole pieces through the holes that I drilled through the front of the body. A couple of delicate hammer taps were required to seat them all level to one another. Once the pickup was installed through the body by way of friction fit, I added a couple dabs of CA glue and attached the magnet to the back of the extended pole pieces.
Step 13: Amplification (Continued)
To install the ¼’’ jack and 500K potentiometer (volume knob ), I drilled slightly over-sized holes to accommodate the components. I then fashioned cover plates out of copper sheet which followed and complemented the shape of the facets. To copy the shape of the facets, I first covered them with masking tape and rubbed a pencil along the sharp outer edges of the facets. I then peeled off the masking tape and transferred it to the copper sheet. Next, using a pair of tin snips, I cut out the shapes slightly undersized and rounded over their sharp edges with a sanding block. I then used an awl to mark hole placements, drilled the holes around their perimeters to accommodate tiny screws, as well as, a larger center hole to accommodate the components themselves.
I then soldered the pickup and the audio jack to the volume pot and used the bottom of the pot as a common ground connection point. I also soldered an additional ground wire (black wire that is illustrated ) to the common ground point of the pot and mounted an the other exposed end to the underside of the bridge. All that’s left to do is install the components into their respective cover plates and then screw them in as well.
*It is also recommended to shield the pickup cavity with copper foil tape, but I like the poeticism of interference noise.
Step 14: Pickup Cavity Cover
To seal everything up, create a pickup cavity cover out of a thin piece of material which either blends in or contrasts the body. I chose to go with the same maple that I used for the neck for design continuity.
Start by covering the hole with masking tape to create a template of the cavity by running a pencil along the hard edges of the opening. *The image of me doing this is dramatically lit because I find it easier to see the edges of the cavity this way through the tape. Then, peel off the tape and cut out the pickup cavity shape with scissors. Stick the masking tape template to the pickup cavity cover material and cut it out, staying well away from the lines. Next, sand up to the lines to ensure a perfect fit. Cut small support blocks to sit inside the cavity that the cover will rest on. To eliminate screws, I inset magnets into the cover and tiny screws into the support blocks, that way, I can remove the cover if I ever need to.
Step 15: Final Assembly and Final Word
The last step is assembly. Insert the neck into the body, double checking to make sure that everything is still aligned and clamp both pieces together. Next, pre-drill holes to bolt on the neck. You can opt to glue in the neck, but I enjoy making various necks for my instruments and often swap them out. Make sure not to drill all the way through the neck during this step! Counter sink the holes on the body, so that the screw doesn’t protrude and proceed to screw both pieces together. The absolute last step is to completely disassemble the instrument and add a coat of finish! I used an oil based, rub-on finish on my instrument to bring out the grain of the wood while still retaining a natural feel. *Also, if you're wondering if I will be adding a knob to my volume pot, I haven't decided yet as I like the steampunk look of it currently. If I do fashion a knob, it will most likely be out of maple and I will add a photo of it!
Congrats! You now have a completed instrument that can be strung up and played!
Install some strings, set up the instrument by tweaking the nut slots and adjusting the bridge and the intonation and then…rock on!
VIDEO SOON. I promise that you will want to hear how it sounds.
Participated in the
2 years ago
As a fellow instrument builder (although not nearly of the same quality) i am very impressed by your instructable. Not only well presented end clear, but with humor and wit. I needed this! Thank you for sharing
Reply 2 years ago
I thought your kalimbas were awesome when you posted them back in 2018! Don't discount your instrument building prowess! And thanks for the kind words, glad I could be of service!
Reply 2 years ago
Thanks! Keep the good stuff flowing!
Reply 2 years ago
2 years ago
It's really super great guitar! I cannot understand why it's not in final!
Reply 2 years ago
I appreciate the comment! My main objective is to share my process and hopefully offer up some useful takeaways, being a finalist is just a bonus!
Reply 2 years ago
Just to share your process? But each of your instructables are done for contest, isn't it? ;) Well, I don’t see anything wrong with that (I do it myself). Contests are a good incentive for creativity.
2 years ago
We'll that's just great very nice job you're talented, now next job is?
Reply 2 years ago
Thanks! Next up will probably be a 3D printed reverb microphone, imagine a microphone with built in spring reverb!
2 years ago
Good job! I’m going to ‘borrow’ that guitar shape for a slide guitar.
Tenor guitars started out as a banjo neck on a guitar body. It was a transition period from Dixie Land style and Big Band swing that forced banjo players to the more sophisticated guitar. You might want to make a strum-stick, a dulcimer with a neck. I made one and it’s loads of fun. An electric one would be even more funner.
Oh, and thanks for using spokeshaves! I often see guitar builders using rasps or even angle grinders. Gasp! I can shape a guitar neck with spokeshaves in a matter of hours, without the dust and noise. The only thing I do to my spokeshaves is add a new thicker blade. The antique Stanley 53 (see picture) with the adjustable mouth is the best, of course your mileage may vary.
Reply 2 years ago
Borrow away! I have a Canadian version of a strum stick of sorts made by Seagull out of La Patrie Québec, called the M4 or Merlin, I have the mahogany one and it's loads of fun to play and sounds awesome!
Angle grinders! Gasp indeed! That 53 is a beauty! I opted for my more delicate miniature brass spokeshaves as the neck is so small. Only took about a half hour!
2 years ago
Well done! As a recent guitar student and hobbiest woodworker and total electronics geek, this ranks pretty highly on my list of things to noodle.
How about a video of how it sounds??
Reply 2 years ago
Thanks! The video is now up! Let me know what you think!
Reply 2 years ago
Sounds excellent! Nice and clean. I see you also opted to put a cap on the volume knob. I like how the whole finished thing looks. Kudos to a great job!
2 years ago
It's gorgeous! And I love the addition of the elk antler. My pup loves those and I knew exactly what it was when I saw it hahah
Reply 2 years ago
Our pup devours them at a rate which seems impossible, which is great for upgrading all of the plastic nuts on my instruments! haha