The neck,
and perfect
fretwork.

The short version

The neck is the part of a build people are most scared of, and they are half right to be. Everything before it you can recover from. A neck that comes out wrong buzzes in certain spots, chokes your bends, and no amount of setup will save it. You go back and do it again.

But here is the thing. It is a patient job, not a clever one. Almost every failure traces back to one of three things: wood that was not dry, a fretboard that was not perfectly flat before you fretted it, or somebody rushing a cut. Get those three right and a first attempt will play better than plenty of factory instruments.

The numbers, in one place

Dimension	Figure	Why
Neck blank thickness	3/4″ minimum	1″ works but means removing more wood. 5/8″ is too thin.
Heel thickness	~3/4″	This part sits in the pocket and does not get modified later.
Headstock thickness	3/8″ to 1/2″	Thinner is flimsy, and tuner bushings have nothing to grab. Check your tuner height first.
Template allowance	1/8″ all round	What the flush trim bit takes off.
Fretboard stock	Just over 1/4″	Leaves material for radiusing.
Truss rod channel depth	~3/8″	Governs how thin you can safely carve the back.
Finished neck thickness	7/8″ on this build	1 1/8″ is too thick for most hands. Preference, within limits.
Fret overhang before trimming	~1/8″ each side	Trimmed flush after seating.

Choosing the blank

Moisture content matters more than species, grain, or anything else. Wood that has not cured will start twisting the second you cut it, and it keeps moving after the guitar is done. You can get away with slightly damp stock in a body. On a neck you cannot.

If the blank starts to bow or twist at any point while you work, stop using it. That is the wood telling you it was not dry, and nothing you do later settles it down.

The quartersawn myth

You will be told a neck has to be quartersawn. It does not. Quartersawn adds a little stiffness, and that is the whole of it. Flatsawn stock that is properly dry with reasonably straight grain builds a stable neck.

A laminated neck, strips turned on edge and glued up, or a contrasting stripe down the center, adds strength too. Also optional, and mostly a decision about how you want it to look.

Reading the grain

Grain does not need to be perfectly straight, just reasonably so. Set the template so the centerline runs roughly with the grain direction. If the grain runs off at a slight angle, angle the neck to match it.

Then look for defects, and pay attention to where they are:

• High on the headstock, not a problem.
• Low on the heel, not a problem.
• In the middle of the neck, now it is a problem. Move the template.

Cutting the outline

Trace the template with the marker held slightly off the edge instead of tight against it. That deliberate gap is your 1/8″ allowance. Cut on the line at the bandsaw and the allowance comes out right.

Before you rout, go back to the bandsaw and trim off any heavy areas. Less material for the router means faster work, longer bit life, and a lot less burning.

Chip out, and how to dodge it

Chip out is the router grabbing the grain and tearing a chunk out of your blank. Sometimes the piece glues back invisibly. Usually it does not.

The causes are all avoidable: too much material left for the router, a dull bit, the wrong speed, moving too fast, or cutting against the grain direction.

Judge by feel, not by eye

Run your hand along every routed edge. A surface can look perfectly smooth and not be. Where you feel a flat spot or a ripple, take another pass. The edge should be as straight as the template.

Burn marks on maple are normal. Maple is full of natural sugar and it caramelises against a bit that is dull or running at the wrong speed. It sands out.

The truss rod

Use a two way rod. If you are building an instrument from scratch there is no argument for fitting a one way.

The rod does not need to run the full length. The movement happens in the middle of the neck, not down at the heel where it bolts to the body, so position it accordingly. Mark where the nut sits and where the fretboard actually starts, because those are different points, and the rod should relate to the second one.

Routing the channel

• Flat bottom bit if the rod sits flat side down. Round bottom bit if you are turning it the other way up.
• Point the adjustment nut up, not down. Facing down means digging deeper into the headstock for access.
• Cut in two passes, not one.
• Test drop the rod before you go to full depth. A test cut here caught the channel sitting 1/8″ off center before it mattered.

Build the jig

Do not eyeball this cut. A jig is a piece of MDF with the neck outline and centerline drawn on it, two straight rails either side of the neck for a tight fit, and two more rails outside those to guide the router base. Set the router in, run it straight through, and the channel comes out straight every time.

Measure your router base width and confirm it is centerd before you mount the outer rails.

The fretboard

Slot width is set by your fret wire

There is no universal number here. The slot has to match the tang of the wire you chose, and tang thickness varies by manufacturer and by fret size. Whoever sells you the wire publishes its dimensions, so work from those.

Saws are sold by luthier suppliers, but the same fine toothed saws turn up at cabinetmaking suppliers for a lot less. Take a micrometer, measure, and buy on the number. Teeth are teeth.

Slot depth

Cut deeper than the tang, but not by much. Radiusing the board afterward removes material at the edges, which means a slot that was right across a flat board comes out too shallow at the edges once it is curved. You will often go back and deepen the ends after radiusing.

Do not cut nearly through the board. It happens on production instruments. It should not happen on yours.

Gluing it on

Titebond II for most work. Original and III both work too, II is just my default.

An even coat, and not a heavy one, because too much glue is as bad as too little. A flooded joint will not close tight and you end up seeing the seam.

Find and mark center on both the neck and the fretboard before any glue goes near either one. A fretboard glued on a hair out of line puts every fret at an angle, and your intonation goes with it.

Clamping

• Use a caul, a thick flat block across the whole fretboard. Clamp straight onto a thin board and it cups between the clamps.
• Go slow at first. It wants to shift as the pressure comes on. Snug it up, check alignment at both ends, adjust, then tighten.
• Start at the center and work out.
• The neck must be dead flat while it dries. Whatever shape it is clamped in is the shape it keeps.
• Sight down the sides for hairline gaps and clamp those out. You should see a little glue squeeze out. You should not see a line.

This is the stage that eats clamps. There is no substitute for having plenty of them.

Shaping

The headstock curve

Cut it on a drum sander against a milled flat board. Before you start, measure the gap between the drum and the board at both ends, because if they are not parallel, the headstock comes out at an angle. Work in passes of about 1/16″ instead of trying to take it in one.

Which side you feed from matters. Come in against the drum rotation, or it grabs the neck and throws it.

Where the profile starts and stops

Set the neck in the actual body and mark where the pocket ends. That is your lower limit. At the top, stop before the point where the thin headstock meets the thicker neck. Carry the profile too far up and you weaken the headstock, and nobody is barring chords up there anyway.

The transition shape itself, a V or a rounded one, is entirely preference.

Profile shape and thickness

A D, a C, a flat D, something closer to a soft V, all of them are valid. There is no correct answer, only what fits the hand that is going to play it.

On thickness, 1 1/8″ is too thick for most people. This build came down to 7/8″. Remember that radiusing takes some fretboard off afterward, so the finished figure ends up a touch under what you measure now.

Carving

A draw knife takes material off faster than a spoke shave. A spoke shave gives you more control. Either one works.

Grain direction decides everything here. Pull with the grain and it cuts clean. Pull against it and the blade follows the weak line and takes a chunk out. Change direction instead of fighting it.

To check your progress, cut a profile template out of card and keep dropping it over the neck, or use a contour gauge taken off a neck you already like.

On tools, a cheap spoke shave will not arrive sharp, and a blunt blade on a nearly finished neck is how necks get ruined. A good one costs real money and pays for itself the first time you use it.

Sanding

80 grit on a random orbital to rough the shape in, then 220 to finish. Move the sander in different directions. Going back and forth in one line leaves flat streaks you will feel later.

Finish by hand with paper laid over the back, drawn along the length. That restores the curve and finds the high spots the sander left.

Judge it by feel. Run your hand and thumb along it constantly. A guitarist's hands will find a difference a ruler never will.

The radius

Radius	Typical of	Trade off
9″	Vintage Fender	Comfortable to hold, but forces higher action, and bends fret out on a tight curve
12″	Gibson	Good compromise, allows lower action
14″	Required by Floyd Rose	The bridge decides this one for you
16″	Modern	Flattest, lowest action you can get
Compound	9″ at the nut going to 14″ at the heel	Best of both, more work, blend the two together then level with a beam

Mark the board with pencil or chalk before each pass. When the marks are gone, the block has touched every part of the surface. Finish at 220, then check with a straightedge and level any high spots left with a sanding beam.

Expect to spend far more time near the nut than up the other end. That end always needs more work. Check the board thickness from the side now and then to make sure you are not favoring one area. If the section near the nut is coming out fat, the neck is bending under pressure or the truss rod is too tight.

Fret markers

Positions 3, 5, 7, 9, 12, 15, 17, 19, 21 and 24. Find and mark the centerline of the board, then find the center between each pair of frets. A ruler laid corner to corner between the two fret slots gives you the midpoint without any arithmetic.

• Punch a starting dimple before you drill. A drill bit set into a dimple goes exactly where you want it.
• Use brad point bits. A standard round tipped bit wanders and goes too deep. Brad points cut a clean hole right on the mark.
• Do not drill to the exact depth of the marker. Leave it standing a touch proud, so that sanding it back with the radius block gives it the board's curve. A marker sitting too deep keeps a flat spot forever.

Materials are wide open: abalone, mother of pearl, turquoise, plastic, stone. Superglue holds them. Sand flush with the radius block, then check the whole board again with the sanding beam, and re flatten the neck with the truss rod before you do.

Side dots: glue in the rod, hit it with accelerant, cut flush with a razor once it grabs.

Fretting

Choosing wire

Crown width and height, tang thickness and depth all vary. The general rule:

• Tall frets need a light touch. Press hard on a tall fret and the note goes sharp.
• Shorter, vintage size wire suits a heavy hand. It fights back less against somebody who grips hard.

On alloy, EVO is a copper and tin alloy with no nickel in it. Hypoallergenic, and a lot harder than nickel wire, which dents and wears fast. Stainless is harder still and lasts basically forever, though it is harder to work. Nickel silver is the cheap standard and the easiest of the three to work.

Fret wear is a hardness relationship. A wound string is basically a file, and whichever of the two is softer is the one that wears. If a customer keeps needing fretwork, look at what strings they are using before you go blaming the frets.

On a refret, expect to need a thicker tang, because old slots widen with age and with the frets coming out.

Checking slot depth

Take a business card, mark the tang depth plus a little onto it, and draw a line between the marks. Slide it into each slot and rock it to follow the radius. Where the line does not reach the top of the slot, that slot needs deepening. Work through every one before you fret anything.

Prepping each fret

• Radius the wire tighter than the board. A 16″ board wants wire bent to about 14″. Wire at the same radius or flatter will not seat, and the ends lift.
• Cut each piece about 1/8″ over on both sides.
• Nip the tang back from each end so it never sticks out past the fretboard edge, and so there is room for filler. Set it back from the very end, not flush with it, because the over radiused wire stretches a little as it seats and moves closer to the edge.

A tang nipper can be made from a sheet metal nipper with a slot ground into it with a Dremel.

Seating

Glue into the slot, fret in, hammer, and it has to happen fast.

Tap one end first, then the other, then work back and forth to sink the middle. Check it is sitting flat against the board along its whole length. If it will not seat, the glue has already gone off or the slot is too shallow.

Trim the ends with ground flat horizontal cutters. A Dremel cutoff wheel gets you closer still and saves you filing later, at the cost of a little risk to the board.

A fret that comes loose at the end, whether now or years later, gets fixed with a drop of superglue underneath and five minutes in a clamp.

Fret ends

A metal file set at roughly 35° in a wooden block does the end bevel in one pass down the neck. You are done when the chattering noise stops and the file edge touches the edge of the board. Figure around ten minutes.

Levelling and crowning

Set the neck flat with a notched straightedge, adjusting the truss rod until there is no gap. Then mark every fret top with a Sharpie and take a sanding beam with 320 grit along the neck, letting the weight of the beam do the work.

Where the marker survives, the fret is low. Keep going until every mark has been touched.

Then crown, and this is the step to get right

Re mark the fret tops. Work the crowning file down each side of each fret, bringing the rounded profile back.

Then round the fret ends over with a small ground down file, the corner on each side first, then the outside edge, until nothing catches a finger.

Polishing and cleaning

1. 600 grit along the fret edges, then across the tops.
2. 1200 grit, same again.
3. Clean with Simple Green before buffing so nothing gets driven into the finish.
4. Buff.
5. Naphtha (lighter fluid) takes off the marker and residue afterward without hurting the finish.
6. Fill the slot ends with matching wood filler, wiping the excess while it is wet.
7. Wax.

The point of all of it

Most factory instruments skip the flat and radiused stage, skip checking that each fret seats properly, and skip the marker check completely. That is why so many shop guitars will not take low action without buzzing.

Doing those three things is exactly what lets you set the action as low as you want. None of them is hard. All of them are slow.

And the formula does not change. Bolt on, set neck, bass, whatever you build next, the only real difference is the heel and how the headstock is made. Build one neck properly and you can build any of them.