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Building an Electric Bass Guitar: Part 3 - Making the Fretboard and Neck from Scratch

by Lee Laird

Click on any picture to see a larger version.

CLICK HERE to read Part 1 of the Electric Bass Guitar Build- Design Considerations

CLICK HERE to read Part 2 of the Electric Bass Guitar Build- Creating the Neck

This is the third part of a multi-part article, relating to building a Bass from scratch. The previous two sections are available in the preceding month's newsletters (at the links above), for anyone wishing to either start from the beginning or to just see what took place earlier. On we go…

Earlier, I made some pencil marks along the centerline of the center piece of the body/neck, corresponding to the 24th fret location and the edge of the nut, closest to the fingerboard. I bought a nut blank (one that is completely rectangular, compared to one that came with the grooves for each string already created) from an online company stewmac.com and I set it up across the neck so it aligns with my mark. To make sure it was oriented correctly, I also placed my small square against the side of the neck area, and referenced both the square and my mark at the same time. With both in line, I held the nut gently in place while marking on both sides of the nut with a sharp marking knife. (You can mark initially with a fine pencil and then follow up with a knife, but it is easy to have a little slip in accuracy.)

For the next step, I removed the nut from the neck. Taking a small square (one that will at least reach the full width of the neck blank) and the marking knife, I put the knife's tip into one of the shallow marks I just made, and while holding the knife still, moved the square up so it just touched the knife's blade at the same time, referencing square against the neck. I held the square securely, with no body parts (fingers, finger tips, thumbs) in line with the square's blade. I made enough passes with the knife, while registering the knife in the mark each time, until it was around 1/32"-1/16" deep into the neck. I then did the same on the mark made on the opposite side of the nut. I like to use a small super-sharp chisel to evacuate the material across the neck, between my two marks, but I work it in from both sides so it doesn't break out the fibers. You could use a small router plane with your chisel instead (if you don't feel comfortable in keeping this area completely flat and level). This small recess for the nut is something I always do but may not be 100 percent necessary. The reason I do this step is so the nut will have a verified reference position, which diminishes some chance of future inaccuracy during a build.

Since the center body section is still square, it is the perfect time to use the Festool Domino to create what I'll use as alignment aids during the glue-up process when the wings are attached to the center section. I placed one of the wings up against the center section, making sure the wing was aligned with the marks I'd made earlier for positioning. Using a large square (one that can reach across the width of the center section and at least part way across the wing) while referencing against the flat side of the center section, I made two fine pencil marks across the joint where the wing meets the center blank. These marks will be the center of each domino and I positioned the dominos so there would be little chance I hit them, no matter what modifications I might make in the future.

Wing held to center section and marks applied.

I removed the first wing from the bench and aligned the second wing on the other side of the center section. I then repeated this process so all three pieces were marked. I used the "old" smallest cutter for my Domino, since I'm not looking for any real strength enhancement from the Dominos and the little dominos will easily fit almost anywhere. Since I planned to add some curvature to the back of the Bass's body I made sure to keep that in mind when setting the distance from the fence down to the cutter, as a partial domino on an exterior surface would look pretty lousy. Before making the "holes", I verified that the depth of cut was sufficient for the domino I chose to use. I'd hate to have slathered glue onto the three parts only to find the actual dominos were too long and prevented the wings from reaching the center section. One other caution is to make a practice joint, especially if its been a while (or the first time) since you've used your Domino. Next, I aligned the center mark on the fence of the Domino with each of the marks previously made, and then created the holes for the Dominos.

Wing pulled away from center section slightly,
to show home made "Domino".

As a side note, I wanted to see how the three sections looked together, so I pulled out four dominos to put it together. Surprisingly, the dominos didn't want to go into their holes. They had absorbed some moisture from the air, even though they were kept in a sealed bag, and had expanded in size. I've run into this once before, and when I was ready to assemble, I nuked the dominos in our microwave, which dried them out and shrank them enough to go together easily. For my testing purposes, I made up a couple of pieces from some scrap that was almost perfect thickness. And it only took a couple extra minutes (shown in photo above).

Next up, I started working on the fretboard for the Bass. I decided I'd make the fretboard for this instrument instead of buying one where all of the fret slots were already cut, as well as having already applied a radius to the top surface. I had a piece of Ambrosia Maple that was long enough and wide enough to easily accommodate this fretboard size. I looked at the grain markings on the board, and found the side that looked best, then planed that side so it was perfectly flat. I marked the board for about 1/4" thickness from the planed side, which is a little thick as I knew I'd need to plane it down to remove the saw marks, as well as flattening the glue side.

Ambrosia Maple board cut to 1/4" thickness,
to make a fingerboard.

After cutting the board to the 1/4" thickness, I measured and cut the width to about 1/2" wider than the final width at the widest end.

Upper right section is the portion that will be the fingerboard.

A little time with the hand plane removed the saw marks from the just-cut edge, and allowed me to bring it to square with the top and parallel to the opposite edge. I measured and found the center of the board, and then marked it in pencil. I squared off one end of the board, where it would rest against the nut of the Bass, and planed it smooth. Most fretboards have some amount of curvature (from side to side), that both feels good in use and works well for stringed instruments. The curvature I wanted on my Bass's fretboard was approximately a 12" radius. I cut a piece of scrap wood to this shape to use as a template when drawing the shape on each end of the fingerboard. I took a 13" piece of string and tacked one end onto a board, measured out 12" and with a pencil, drew an arc, keeping slight tension on the string. I cut this out at the band saw and used a spokeshave to bring it down to my line. I made a tick-mark on my "template" at approximately the center point of the arc, and set this so it matched up with the centerline on the fretboard. I shifted the template until each edge was intersected equally, and then drew the arc on the fretboard ends.

End of fretboard showing the signs of planing down
towards the arc.

Paying attention to the grain of the fretboard, I planed the outside edges down close to the arc, and then worked incrementally towards the center of the fretboard. I used some sandpaper to remove any slight contours that remained and then sanded up through 600-grit for a great feeling fretboard.

Now it was time to think about cutting the slots for the frets. The first step is to lay out all of the fret locations, which is crazy precise work. I have a chart that provided the measurements from the center of one fret to the next, and all are shown to the third digit to the right of the decimal! I ended up using a digital micrometer to help retain accuracy. The first fret was 1.906" from the nut, so I moved the jaws of my micrometer out so it read exactly the same value on the digital screen, and locked it in place. I pushed one of the legs up against the end of the fretboard, at the centerline, and touched the other leg to the centerline down the board. I used a fine marking knife up against the inside of the second leg, and pushed the tip of the knife lightly into the wood. I changed the distance on my micrometer so it matched with the distance from the first to second fret locations, placed the first leg lightly into the knife mark made at the first fret location, and again touched the second leg down on the centerline.

Using a micrometer to precisely identify fret locations.

Using the marking knife up against the inside of the second leg, I pushed the tip in lightly. I repeated these steps, changing the distances between frets per the chart for all 24 frets. After making the small mark for all of the frets I went back with my small square, put the knife back into its mark, slid the square up so it was square to the edge, and scribed full-width across the fretboard at each location.

Using square and marking knife to scribe fret locations
full-width across fingerboard.

For the next step I made a jig that would keep my hand saw square across the board, as well as perpendicular. I also installed a clamp, so I could place the fingerboard exactly where it was needed, and then made sure it could not move during sawing.

Jig for cutting frets with a handsaw,
showing fretboard, saw and clamp.

I let the saw plate engage each knife mark, locked it down, and lightly sawed down each slot. I did my best to keep the saw completely horizontal, but I'm sure it varied a bit. Ultimately, you just need to make sure you have cut deep enough for each fret to install completely but not so deep as to cut all the way through the board. You also need to leave a little margin for some superglue, which will make sure the frets do not work their way back out in the future. Each style of fret wire can have slightly different dimensions, so make sure you test what you have before cutting on your hard worked fretboard. (As information, I'll probably buy future fretboards with the slots already cut, unless I am building an instrument that requires a custom scale or other custom feature, as the time I spent making the fretboard makes it one of the most expensive around.)

I measured the approximate final width for the neck at the nut end and marked it equally out from the centerline on the fretboard. I repeated this with the final width at the bridge end of the fretboard, and then drew a line connecting the two outside points on each side. To cut the fingerboard to this shape I used a jig I made from a rectangular piece of MDF that has three clamps that hold the fingerboard in place.

Close up of end of the jig.
You can see the line over the jig edge.

I made certain that none of my clamps were overhanging on the edge of the jig, so they wouldn't come in contact with the table saw blade. The jig also has a small screw inserted into the top surface towards its end, so the fretboard blank is against it, which removes any potential for slipping backwards. I set the table saw fence so the edge of the jig just slides by the blade (with it off) without hitting it, and locked the fence in place. I put the fingerboard onto the jig, aligning the edge of the MDF jig with the points at each end of the fingerboard, and locked the clamps down. I set the table saw blade so it was high enough to cut completely through the fingerboard. I made sure to use enough width on my jig, so it didn't bring my hand too close to the blade. When cutting the fingerboard, I made sure to keep slight pressure on the jig, towards the locked fence, so it works as intended. You can also install a vertical handle on your jig, if desired, but I feel comfortable using the clamp bodies as hand holds, as they'll never get near the blade. Once the fingerboard was completely past the blade, I turned my saw off using my left thigh against the emergency paddle, so I didn't start reaching around with the blade spinning.

Post cut with off-cut next to
fingerboard for better
understanding.

After completing the cut on the first side of the fingerboard and then shutting the saw off I unclamped the fingerboard and turned it around so the markings on the other side would line up with the jigs edge. I repeated the process and was then finished!

Now that the fingerboard was cut to its final shape I put it onto the upper surface of the neck. I put the nut into its slot and slid the fingerboard so the narrow end was up against it. I lined up the center of the fingerboard with the centerline on the neck, and used a fine mechanical pencil and drew along the sides of the fingerboard so they were dark enough to see clearly. Later I'll make cuts along these lines at the band saw.

While the center body/neck blank is still square, it's a good time to install the truss rod, whether you've made or purchased it from a parts store. (**Before moving forward, know that I never route for a truss rod until the actual piece is in my possession, as there might be small differences in size, that could make for extra work after the fact.) I took the truss rod and laid it out on the neck, along the centerline, and positioned it so the adjuster would be accessible through the headstock design I used. I made a mark at the other end of the truss rod, again on the centerline, so I knew the exact area I needed to evacuate with the router. The truss rod I used in this build is a double-rod version (from stewmac.com), and is the same dimensions, except for its length, as what I previously installed into the Les Paul I made. This makes it easy, since I have the router bit that I bought for the previous truss rod, and it makes the perfect sized slot to install this new truss rod. I didn't need a heavy-duty router to make the slot for the truss rod, since the router bit is a fairly small diameter, and I'll be taking it with multiple shallow passes. (Always remember to lock the depth control, as you don't want the bit to start diving deeper than intended.) The main thing I look for is to have a router that has easy depth controls, as well as a solid fence, that will ride along the side of the blank.

I set the fence so the center of my bit lined up with the centerline on the blank, and then locked the fence. I made sure to keep some pressure on the router fence during the actual routing as I have seen bits wander and even though no one would ever see this error, I don't want anything that might rob the tone of my Bass. I intentionally left the angled-back headstock cut for later so that the blank had a flat reference for the router to ride on, well past the location where routing could stop. I drew the angle of the headstock on the side of the blank before routing, so I'd know exactly how far down the neck I needed to route. I routed slightly beyond this end point, just to give myself a little extra buffer.

Headstock end of the neck,
with rearward angle drawn.
Red arrows point to
somewhat faint line.

When we cut this end of the neck so it angles backwards, the earlier-routed section beyond this cut will be removed.

Truss rod at partial depth.

Once I got close to full depth, I tested it with the actual truss rod, as that is the most accurate method to know what is real. I snuck up on a perfect fit, but even that had a minor issue. The back section of my truss rod was perfectly flush with the top of the neck, but the section closest to the headstock was still just barely high. It turned out the section that was high was actually just that much taller than the back section, and the adjustment head hung slightly low. When I determined what was going on, I used a small chisel to evacuate a thin section of wood in just that region, making everything spot on. The style of truss rod I'm using doesn't require a filet of wood (as some do) between the rod and the fingerboard that will get glued on above it later. If you are using a different type/style of truss rod, check your installation instructions for guidance.

The last step we'll get through in this segment is to cut the headstock angle from the lines I drew on earlier. I used the band saw to cut just outside of my line, and then used a hand plane to clean up the saw marks and made the surface flat and square to the sides.

Headstock cut at band saw. Red arrows point to off-cut.
Working towards flat with hand plane.
Verifying square on flat headstock.
(Red arrows show slot for nut, not shown earlier.)

I didn't cut the back side of the headstock earlier, as I wanted to retain the support behind the top surface, allowing for the best result with a hand plane.

In future segments I'll show how a few cuts on the center section will make it so others don't just see a stick of wood, but can tell that you're actually making an instrument (or at least its supposed to have that affect). I will also start work on body shaping (not mine, the Bass's) and one of the most important parts, shaping the neck.

I hope you enjoyed this article and please let me know if you have any questions or comments.

Lee Laird

CLICK HERE to learn more about the Festool Domino Joiner


Lee Laird has enjoyed woodworking for over 20 years. He is retired from the U.S.P.S. and works for Lie-Nielsen Toolworks as a show staff member, demonstrating tools and training customers.
You can email him at lee@lie-nielsen.com .
or follow him on Twitter at http://www.twitter.com/is9582 .


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