Making Necks

The procedures I use for making necks have also changed over the years. Since I have the pin router its used for almost all of the neck making procedures.

In production there are also a few ways to produce necks. The way I describe in the large factory section is using a CNC to cut out the basic shape and then do the back round over. This way still needs allot of hand work after the neck is cut out.

Many companies use a copy machine to make necks. Basically they have a mold of the neck shape and the copy machines using blades makes an exact copy of the mold. This is a very quick and efficient way to make necks and the results are very consistent.

I feel the best way to make a neck is by hand , but many companies nowadays are using a ball mill cutter and a digitizer.

Many CNC machines can have an attachment on them called a digitizer. The digitizer is a small ball attached to the CNC's main head that moves in every direction, up, down and side by side. First you need a good shaped neck. Usually the proto type will be made by hand or it could be one that was on someone's guitar that they really liked. (This is what Music Mann stated in the Eddie Van-Halen model)

The computer lowers the digitizer into the sample neck and slowly moves the sensor around the neck very slowly. At this time the computer is recording every movement that the ball rides on.

After the digitizer completely records the information into the computer, the computer can rerun the program exactly the same way that the digitizer traveled.

The digitizer is removed and the standard ball mill bit is put on the router and the program makes a perfect copy of every detail of the first neck. If there are any imperfections in the sample neck the computer will copy them but actually smooth them out. For example if there's a big dent in the sample neck the digitizr will copy it but because it can't make a puncture in the wood like a dent it will smooth out that area.

Companies like Martin and Taylor use Fadal machining centers to make necks. These machines were originally made for milling metal parts but slight modification on them can easily make guitar necks. These are very expensive machines but they have tool changer's on them that hold the tools in place with suction. This saves time from having to change the bits by hand and the machine can perform many operations one after another so that the neck could actually come off the machine and only need some final sanding.

I have seen these machines do the truss rod channel, fretboard radius, fretboard position marker, machine head holes and even in some cases cut the nut and fret slots. If you ever get a chance to go to the Martin Factory they have daily tours and you can view this process in person.

Unfortunately we all don't have an extra $100,000 or so to spend so lets make a neck with some basic hand tools and also with a pin router.

First when you are about to make a neck there are many things you need to think about. First what is this neck for? Is it a bolt on, set in or neck through? What scale, neck material, shape and construction will you do?

Neck Construction.

There are basically four types of neck construction I use and I only use Quatersawn wood for any neck. The price for Quatersawn is worth it in strength and durability. I can understand why companies that purchase log lumber wind up using flatsawn to get the best yield but I would not recommend this to anyone that is making a neck to play.

The first neck is a standard one piece with a straight headstock. This construction is used on most Fender style guitars. One draw back is the need for either a two string trees to hold the strings down so that they have enough angle and don't come out of the nut or the use of staggered machine heads such as Sperzel Trim locks. This type of neck construction is fairly simple and is the only one that the truss rod is usually inserted in the back of the neck.

The second type of construction is a one piece neck with a angled headstock. You don't see very often because depending on the angle of the headstock it is not that strong and it can be waste good wood material. This type of neck I use for making modified Strat style necks that don't need string retainers. To do this cut the headstock to a 4 to 6 degree tilt and install the truss rod on the top of the neck before the fretboard is glued on.

Three piece necks are very strong, these are made by taking a standard piece of wood and cutting out the side shape of the neck in three pieces, then glue the pieces together with the middle having the opposite grain for strength. These necks are fairly easy to make and I use these for all set-in neck construction.

Scarf Joint necks with angled headstock are what many acoustic, neck through and locking tremolo guitars use. This type of construction takes one piece of maple and depending on the tilt of the headstock, cut the wood on an angle between 10 degrees and 14 degrees and glue the piece back on the neck in the opposite direction. This is the type of neck I used for most of the bolt on locking nut guitars I make.

Truss rods.
There are a few truss rods that I use and there are many truss rods out there that I would never use for one reason or another.

Rear Channel Rods.
This is a basic Fender style rod that is inserted in the back. This type of rod is just basically a long metal bar that has one end permanently locked into a position and the other end is threaded. The slot that the rod is put in is routed on a slight curve so that when the nut is tightened the rod will pull closer together and straighten the neck.

Aluminum Channel Rods.

This is what you see on many acoustic models. I never use this rod because of the amount of wood that is removed. First the wood is not that strong after that much wood is removed, and second I feel that most of the sound from the necks wood is also removed.

Standard Single Rods.
These are almost like the Fender style rods but the slot is usually straight without the curved rout. These work well but the truss rod has come along way since the days when this was popular, and installing most of the other rods uses the same procedure so I would prefer using a different rod.

Double Rods.
The word "double truss rod" does not mean two way. Basically a double rod uses two bars that are welded together at the ends. There is one nut on the front end and when it is turned clockwise the truss rod tightens together and straightens the neck.

Two Way Rods.
These truss rods are almost the same construction as the double rod using two rods but they work by contracting and expanding the rods. If you turn the nut clockwise the rod is compressed and tightens the neck and if you turn the nut counter clockwise than the rods expand and actually add relief to the neck.

I would like to use two way rods but until I find one that does not have a neutral spot I will stick with the double rods. I have tried many two way rods but the problem is that there is a small area between the clockwise and counter clockwise positions. This area causes the rod to be loose and rattle. If it just happens that this is the exact position to set the neck up than the inside of the neck will rattle.

I prefer and really only use double rods at this time. I also only use ones that have the round bottom bar round and a top flat bar. I feel that the ones with two round bars do not touch the fretboard correctly where as a flat double rod will.

Headstock Angle./ Machine Head Placement.
I do use straight headstock's sometimes if people ask for it, and only with Sperzels and six machines heads on one side. If the guitar will have a standard non locking tremolo than I would probably make a one piece neck with a 4 to 6 degree headstock tilt and six in a line machine heads. I have found that any greater of an angle on a headstock with six in a line and a standard nut will not stay in tune without allot of work. If the guitar is going to have three and three tuners than I would use a 10 to 14 Degree headstock angle and if the neck is a locking tremolo with a locking nut I usually use a 14 degree scarf joint.

Scale Length
Fuguring out fret placement is easy these days with programs like Excel. Just take the total scale length say 25.5 and divide it by 17.817 to figure out the distance to the first fret, Then take the scale length subtract the distance to the first fret and divide this by 17.817, continue till you get all the fret placement. This is sometimes called the 18th rule.

I pretty much stick with the standards on this if the neck is bolt on neck and uses a tremolo I will use a 25.5" scale and if the neck is a set in and uses a non tremolo bridge I always use the 24.75" scale. For basses I use standard 34" scales for almost all of them except for five and six strings that I would maybe use 35" so that the low B string does not flop around.

Fretboard Radius.
This has to do with all the other options on the neck, mainly the bridge style and scale. If the bridge is a tune-o-matic or FloydRose® than the saddles are preset to a certain radius and this is the one that you should use, because you can modify the nut to a different radius there is a little option even on some non adjustable bridges but this tends to be more trouble than its worth.

The main purpose of fretboard radius is personal preference this is not a guarantee but generally people that dig in the notes like rounder boards and technical players that bend the higher notes and play fast tend to like a flatter radius. Again this is not gold just the standard that I have come to know.

Fretwire Size.
I have talked about this in other parts of this book so I won't go into details again but for rounder radius fretboard's I use lower thinner frets and for flatter boards I use higher frets that are sometimes wider also.

Now that we have that out of the way, here is the basic way of making a neck.

The minimum tools I would suggest for these are a band saw, hand router, drill press, belt sander, drill bits, router-bits, round over bits at 20to 25mm(3/4"-1.0")Sand paper 80/180/220/320/400.

First you need to make a drawing and figure out what type of neck you will make lets say this will be a bolt on neck that is 25.5" scale has 24 frets a 430R (17") fretboard radius and will be a thin wide neck, Say 18mm thick at the first fret and 20mm thick at the twelfth fret. The width of the neck will be 43mm at the nut and 56mm at the 24th fret. No binding, quatersawn maple neck with a rosewood fretboard , a 14 degree tilt back headstock and a locking nut.

This is the formula that I will need to make a drawing for it. Always the first thing to do is make a center line that everything will follow then layout the entire neck drawing to scale. From here I make the templates.

Personally because I have a pin router I will make one template for the neck and one template for the headstock, This is because the neck will have a tilt and I will need to do some work on the headstock laying it flat. If the neck was a straight headstock I would use just one template.

Next I get the wood ready, I have found that the best way to make a neck is to start from the exact thickness wood needed. For example if the neck at its thickest part is 25mm (At the neck pockit) and I will use a 4mm thick fretboard I will plane the wood to 21mm before I even start making the neck, once the neck is glued up I don't want to have to remove any extra wood just shape the back and its done.

   

Once the wood is planed to 21mm I locate the scarf joint on the neck I want it to start at the third fret for strength use a chop saw set for 14 degrees for this but a miter saw or very steady hand on a band saw will also work, (my hands are not that steady I would make a jig)

 
 Cut the scarf joint and if you have a jointer plane the wood flat if not use the belt sander to flatten the surface. Once the wood is ready for gluing take a small amount of water and open up the cells in the area that will be joined they were crushed when they were sawed so the glue could easily come loose. Just dampen the area and wait for it to dry before gluing it up.  

 
After the wood is glued and dried make a straight center line down the middle of the neck and use double stick tape to attach the template. Band saw the basic shape of the neck at the fretboard be careful around the headstock area. After the neck is band sawed to the basic shape I use the pin router with a 12mm bit and pin rout to shape the fretboard part of the neck. Without the pin router I will wait until the fretboard is on before I finish shaping the necks dimension.

 
 

  Next figure out the location of the truss rod and the width and depth that will be needed. The best way for this is to put the truss rod channel in the template then just use the proper bit in the hand router and rout the slot. For routing the slot with the pin router, I have a fixture that I made just for routing this slot, It holds the neck in place and the slot is under the jig and follows the pin.After the truss rod channel is routed install the rod and make sure that it is not loose it should fit tight with no rattle if it does not fit tight I recommend covering it with a heat shrink tubing to make it snug. For fretboard's I purchase them already slotted because the time it takes me to set up the radial arm saw and accurately slot a fretboard is not worth the headaches when people that have gang saws can do it in seconds. Many places like Exoticwoods or Stew Mac have these.

   

Take the fretboard and draw the center line on it and line it up with the neck, when you clamp it up the fretboard tends to move so before I glue up the board I take four small finish nails and hammer them in about 4mm the neck at the first fret and the last fret and use end nippers to cut the tops off. Then line up the fretboard on the neck and push down, the fretboard will have imprints of the nails in it then use a small drill bit to drill the pin holes in the fretboard. Put the fretboard back on and make sure it is straight.

Remove the fretboard and apply woodworkers glue to the fretboard and neck and put them together. Wait a few minutes before clamping it just until the glue is tacky.

To clamp the fretboard, I made a clamp that just touches the ends for pre radius fretboards. Be carefull with these because the center needs to be exact or one side may be too thin.

Once the neck is set up, band saw the extra fretboard off and put the template back on and final shape the neck with the fretboard on. I have a jig that has the position markers already in it with small nails to mark the exact location of the fretboard markers. Other wise I would have to measure each one using the fret slots to find the center and the center line. Drill and install the position markers and sand them flat to the fretboard.

Use the headstock jig to final shape the headstock and mark the machine head holes. On my template the holes are in the template and I just drill through the holes to place the machine head positions, it save time having to measure each one. Again its better to use forstner bits for any holes that go through the wood.

Before final shaping of the neck install the side markers in the neck, again I have a jig that marks the exact location for each one. Drill and insert the side dots.

Once the headstock is shaped you will need to take the thickness of the headstock from 20mm to 14mm to do this I use the pin router holding the neck on an angle with the headstock flat, If I did not have the pin router I would measure it and band saw the extra off then clean it up on the belt sander.

   

At this point I want to shape the back of the neck, for this I also made a jig for the pin router. Depending on the necks thickness I use different shims to hold the neck up higher on the nut end of the neck. This holds the neck 2mm higher so that when I shape it on the pin router the neck will be shaped 2mm thinner at the nut area. If I did not have the pin router I would rough shape the necks back radius on the belt sander.

  Now comes the fun part final shaping. First rough out the fretboard radius so that when you hold the neck in you hand it feels natural then use round files to shape the actual necks back profile to the desired feel. Keep checking the shape with your hand and feel each are of the neck to make sure it is what you want.

Once the neck is final shaped I use a 80 paper by hand to clean up the file marks and then 180/220/320 paper on a orbital sander to final sand out the neck.

The neck is basically finished at this point we just need to make sure that the neck is straight and that the fretboard radius is correct and fret fret it.