STEP BY STEP -6
I have always made laminated necks for my guitars, so that is the method I will discuss here. I do this for two reasons. First, while mahogany is an incredibly stable wood, by laminating it I believe that I can minimize any likelihood of warping in the future. Second, I love the look and it has become my "trademark", so to speak. In recent years I have come to believe that the added stiffness from a laminated neck may have an impact on the tone of the guitar. The theory is that the neck tends to absorb vibrations from the body and a stiffer neck does less of this, improving tone and sustain. Can I prove this? Of course not. But it does make sense to me. I do note that many other makers these days are adding carbon fiber strips to their necks so they must like the notion of a stiffer neck, also.
Select mahogany neck stock. 4"
x 28" x 12/4 stock.
Mahogany is a wonderful wood and it is generally not hard to find clear stock. Nonetheless, look for clear stock with no worm holes, no end checking (or, at least, enough extra wood to allow cutting off the end checking) and dry. 12/4 stock (i.e. 3" thick) requires me to glue on small ears for the full peghead design. I would rather do than than pay the expense (and see the waste wood) for 16/4 stock.
Split neck stock in half, lengthwise.
Taking my stock I split it lengthwise so that I have two strips that measure 3 x 1 1/2 x 28.
Flip sides and joint glue surfaces.
One of these pieces I flip over (not end to end). That way if the grain is even a bit off straight the two pieces will have grain going in opposite directions and any tendency to twist or warp will be naturally counteracted. I join the gluing surfaces on my jointer and always put in a new set of blades. I can get a joint where the two pieces of wood almost stick together by vacuum.
Thickness plane sides to parallel.
Next, I thickness plane the pieces so that the sides are perfectly parallel. The reason for this will soon be evident.
Prepare maple and rosewood laminations - 4" x 28' x 1/8".
Pretty simple. I use maple and Honduras rosewood for my laminations and either buy it in this thickness or plane and sand pieces I have cut. I also cut them to the same size as the pieces of the neck block.
Glue up neck block.
Pretty straightforward. I use a nice flexible plastic spatula to spread the glue and use heavy pipe clamps to apply the clamping pressure. I can generally do two blocks in each glue up, using wax paper to separate the two blocks.
Joint fingerboard surfaces flat and square to laminations. Square
up ends of block.
Again, fairly straightforward. The secret is a good jointer. The object is to end up with laminated blocks that can easily be cut into neck blanks.
Lay out 2 neck blanks with templates.
I can get two necks out of each block, by nesting the two profiles. I carefully lay out the necks at this point using plastic templates. I have different templates for different scale lengths and for 12 and 14 fret models. I also make sure the block is large enough for the required heel length.
Band saw two neck blanks.
No great tricks here. Carefully band saw on the outline marked out in the previous step.
Cut truss rod slot on shaper.
I use a single compression truss rod, much like the Gibson company has used for many years. This style of rod works best if it is laid in a channel down the middle of the neck which is deeper in the middle than at either end. Cutting this curved groove may seems difficult but is really not if you have a spindle shaper or a router table. I use a spindle shaper. I have made a jig which has the curvature I want for the bottom of my truss rod slot cut into the front edge. The neck blank is mounted and firmly clamped with the fingerboard face vertical. The spindle shaper has a 1/4" cutter with a radius on the end and a ball bearing follower on the same shaft. This way the follower rides along the curved surface of the jig and the cutter cuts a groove in the neck with a matching curve and at the right depth. Groove cutters are available for routers that will do the same thing if mounted in a router table.
It is worth noting that this step is the reason I want the neck blank to be perfectly parallel. If it is not it would be very difficult to have the groove run perfectly down the middle of the neck.
Rough trim neck blank to size and fingerboard taper.
At this point we begin an extended process of removing wood from the neck. A lot of this process can be done quickly with a band saw, shaper or sander. My first "cut" is to trim the shaft roughly to the taper of the fingerboard and rough shape the heel and the peghead.
Rough trim heel.
For most guitars I do this with a jig on my shaper since it is quick and easy. A band saw will also work well. At this point I am not looking for final shape but just to remove a lot of excess stock in a hurry.
Cut dovetail and verify set back angle vis body.
The dovetail is cut on a special router jig (matching the one I used for the body) so that it will fit perfectly on the body. To ensure that the neck is straight the jig centers the neck on the truss rod slot. To ensure that the neck set back is correct the jig can be adjusted to this angle. I generally cut a test piece and try it in the guitar to ensure that this angle is correct and will not require hand adjustment later.
I use a traditional tapered dovetail joint on my guitars. These days there is a lot of (silly) controversy about different methods of neck attachment. The tapered dovetail is the "traditional" method and I use it because it was really the only option available when I started. These days many makers are using one form or another of a bolt on neck. My sense is that these methods work well and are every bit as good as the dovetail and are easier to work on down the road. Some people argue that one or another method sounds better and I simply do not hear it and I cannot imagine a way to scientifically test this proposition. So why do I continue to use a dovetail?? Well, I am set up to do it, I am quick at it and it works well. Plus, I am probably too stubborn to change at this late date in my life.
Glue peghead ears if necessary.
If the blank is not wide enough for my peghead shape (it generally is not) I glue little ears onto the peghead to make it wide enough. I make these ears out of scraps from the neck blank so that the color of the wood matches well and I try hard to ensure that the grain of the ears runs the same way as the main part of the peghead.
Plane peghead face flat and to correct location.
The critical element in the peghead (at this point) is that it be flat (easy to achieve on a jointer or sander) and that the angle of the peghead begin at exactly the correct spot relative to the nut end of the fingerboard. I have made several carefully calculated templates to ensure that this can be done quickly and accurately. The actual cutting is done on my jointer with, perhaps, a bit of touchup on the belt sander.
Locate and drill gear holes.
This is a simple bit of layout work. If you are planning to make many guitars (or even two) with the same peghead shape a template is the best method to ensure accuracy. I have made a template which has hardened steel drill bushings in it to use as a drilling jig. I clamp the jig to the peghead and simply drill through the drill bushings - voila, 6 holes in exactly the correct location!
Rough trim peghead.
Quickly done on the band saw.
Shape peghead on shaper.
I use my shaper to do the final shaping of the peghead. I have a jig for each peghead shape I use. The jig has dowels that fit into the gear holes I cut in the last step. The shaper is set up with a straight cutter with a ball bearing follower that is the same size, so it will cut a peghead exactly the same size as the jig. It helps to have a shaper that can cut (rotate) in both directions - this helps to protect against chip out on the edges of the peghead.
Prepare truss rod.
I make my truss rod of 3/16" drill rod. It has a small square anchor at one end. I thread the rod into this end with a 10/32 tap and die. I feel that this is stronger than a weld and I do not want this to break, EVER!!!
Cut anchor pocket for truss rod.
I place the rod in the truss rod slot and mark around the anchor. I then cut out a pocket so that the truss rod is flush with the end of the dovetail end of the neck. I used to use a Dremmel tool for this but these days I use a laminate trimmer, a small router that is much more powerful than the Dremmel.
Prepare truss rod filler.
The truss rod filler is maple and fits very closely in the truss rod slot. The bottom is shaped with the same curve as the groove so that the truss rod will be forced to the curve of the slot.
Glue in truss rod filler.
A simple job. I lightly coat the sides of the filler strip (but never the bottom) with glue and place it in over the truss rod which is laying in the slot. About three clamps ensure that the truss rod is fully "bottomed out" in the slot. When the glue is dry I trim off any excess filler strip flush with the fingerboard surface of the neck.
Cut pocket for truss rod nut.
The truss rod is threaded on the peghead end for a distance of perhaps 1 - 1 1/4" , matching the tread of the brass acorn nut which I use as the adjusting nut. (I buy these from Gibson or from Stewart Macdonald). A small pocket must be cut for the bearing washer and to allow access to the nut. I cut this with a tool called a counterbore. This tool (see photo) has a projecting rod that slides into the truss rod slot and cuts a flat bottomed pocket perfectly centered on the truss rod.
Tension truss rod.
One complaint about the single rod compression truss rod is that it only acts to remove excess relief (forward bow) in the neck and cannot be used to remove back bow. This need not be. After the truss rod is fully installed and the neck shaft has been cut roughly to shape (i.e. remove excess stock so that its stiffness is close to that of the final neck) I pre tension the rod. This puts a small amount of back bow into the neck.
Flatten fingerboard surface of neck.
Once the neck is slightly back bowed I then take it to my belt sander (which has a perfectly flat table under the belt) and sand the fingerboard surface of the neck. Thus when the neck is assembled if I need to remove or adjust any back bow in the neck I have only to loosen the truss rod nut and - voila!! - I have a double acting truss rod. In practice this is remarkably simple and effective.
MAKE FINGERBOARD AND ASSEMBLE NECK.
Select ebony blank for fingerboard.
Mostly I look for clear wood with no knots. I kind of like the look of ebony with brown or gray stripes, and in any case the color generally turns completely black after a short while. If the grain is wavy or does not run straight down the length of the fingerboard I will generally reject it. While ebony is the traditional "premium" wood for fingerboards, it is not the only choice. Many of the rosewoods can and have been used along with many others.
Joint neck surface of fingerboard.
I use a jointer to true the neck face of the fingerboard. The difficulty here is finding a way to hold and push a relatively thin piece of wood over the jointer without hurting your hand. I use a fairly heavy piece of maple which has been jointed flat and then I have put a piece of 1/8" maple on one end to act as a "hook". This catches the end of the fingerboard and I can then push the ebony down and forward without danger to my hands.
Locate and drill jig location holes.
Because I am trying to produce a number of guitars at one time I need to create jigs that help speed up the process and make the parts of the guitar more uniform. Fingerboards are a good area to do this. I have made a jig of Baltic birch plywood with two small (1/8") drill bushings at either end. They are spaced outside the effective length of a finished fingerboard but within the normal length of fingerboard blanks. I drill these two holes in the center of each fingerboard. These holes will act as locators for all of the subsequent jigs.
Cut taper for fingerboard profile on shaper.
I have made a jig for tapering my fingerboards on the shaper. (A router table will do just as well) It is quite simple, just a long board shaped to the exact taper that I use. It has pins for the holes in the fingerboard and toggle clamps to hold the board down. I make the rough board wider than I am likely to use and then simply trim to correct width by running the edge through the jointer. I find this easier than making separate jigs for each possible fingerboard width.
Cut 14" radius shape for playing surface of fingerboard.
There are many ways to do this essential task The way I do it is with a small thickness planer/molding cutter ( W & H, for those of you who might be familiar with this old time but very solid bit of machinery). I had a set of custom knives cut with the 14"radius curve that I use (Martin generally uses a 16" radius board and Gibson generally is closer to 12" radius). I then made a jig that locates the board with pins in the holes mentioned above and which also utilizes vacuum pressure to clamp the board firmly down. A quick run through the molding cutter and the board is arched the way I want.
There are other ways to do this. A number of the supply houses (LMI, Stew Mac) sell radiused sanding blocks. A judicious combination block planing and sanding will produce a nice arch.
Cut fret shots.
Here again my method may not be readily available to others. Many years ago I had a machinist make me a small saw for this purpose. It uses a single overhead blade and a table that slides under the blade. The board is attached with the locating pins and a vacuum hold down to a jig that has slots corresponding to the fret scale cut into the bottom. The sliding table has a feeler which fits into these slots. By moving the jig step by step from slot to slot I can quickly cut the fret slots with a high degree of accuracy and repeatability. Many other methods are available, including buying a pre slotted board.
Drill locating holes on underside of fingerboard.
The locating holes I have used to this point to locate the fingerboard on the various jigs will no longer work since they are outside of the area of the actual fingerboard. For locating the fingerboard on the neck I use a separate set of locating holes. There are 3/16" in diameter and are drilled using a jig very similar to the one I used to locate the earlier set of holes. This jig is made of Baltic birch plywood and has two hardened steel drill bushings. The holes are drilled near the 1st and 12th fret and one on each side of the centerline/truss rod. For fairly obvious reasons these holes do not go all the way through the fingerboard. When used to locate the fingerboard a matching set of shallow holes is drilled in the neck and I use 3/16 nylon rod as the locating pins. Works very well indeed.
Verify and adjust width at nut for each instrument.
This may seem obvious but is still critical. It is much easier to machine the fingerboard to the exact correct nut width when it is off the neck. I use a jointer or a belt sander to do this and to maintain a perfectly straight edge.
Prepare and install inlay as necessary.
Inlay is a whole separate topic - so I will leave that to others better capable than I. Dots are done with a matching drill and snowflakes are done with a small dremmel router.
Drill holes and install side dot markers.
I use side dots that are 1/16" in diameter (I buy them as a plastic rod from Stew Mac. It is really quite simple to measure for the middle of each fret position and drill a shallow hole. A dab of Duco and push the rod in, snip it off and do the next. For those of us doing production (or who are simply compulsive jig makers) I have made a jig that automatically locates the position to drill the holes. It is really simply a metal bar with holes drilled at the correct positions for a given fret scale . Toggle clamps hold the board in position and I quickly drill the holes.
Final sanding and truing of fingerboard surface.
At this point I prepare the surface of the fingerboard. Using sanding blocks with the correct curvature I sand the board successively to a final grit of 320. Then, suing a small triangular needle file I gently run the file along each of the fret slots, putting a very slight bevel on the top of the slot. This helps the fret go in a bit easier and decreases the likelihood of chipping the fingerboard when the guitar is later refretted.
Install frets .
These days I install the frets with a arbor press. On the working end it has a brass "shoe" matching the radius of the fingerboard. I tap in the end of each fret and then press in the fret with the arbor press. This is a very quick, efficient and uniform method of installing frets. But not absolutely necessary. For the first 300 or so of my guitars I installed frets by simply hammering them in with a brass hammer. the secret to success with this method is that the board must be firmly mounted on a solid surface. I used a piece of steel I beam which I had trued to a perfectly flat surface although other methods will work.
Locate and drill location holes on neck blank, dry fit fingerboard
and verify correct location.
Using the same jig I used to drill locating holes on the fingerboard, I drill matching holes (perhaps 1/8" - 3/16"deep) in the neck. I then make the nylon rod pins and test the fit of the neck to the body.
Test and adjust dovetail as necessary for centering and back angle.
If the neck does not properly fit the body for any reason, this is the best time to fix it since the fingerboard is not glued in place and can be gotten out of the way. So I do, making sure that it is perfectly lined up on the centerline of the guitar and that the back angle of the neck is correct.
Dry fit fingerboard and install peghead faceplate.
The next few steps are necessary for me because I bind my peg heads. Many makers do not and if you choose not to do so you can skip several of these steps. The first step for me is to fit the board to the neck and then fit the peghead overlay. I place the nut against the fingerboard and slide the overlay (generally ebony for me) up tight to the nut. Then I clamp it in place, making sure that it does not slip. This gives me a ready made slot for the nut.
16. Trim faceplate to size.
I generally trim the overlay to size with a trim bit on my router.
The critical element here is to carefully cut and sand the curve or
flare from the fingerboard to the front corners of the peghead. This
must be exact so that I can cut binding ledges in the correct
place. At this point I remove the dry fit fingerboard and proceed
with finishing the peghead.
The critical element here is to carefully cut and sand the curve or flare from the fingerboard to the front corners of the peghead. This must be exact so that I can cut binding ledges in the correct place. At this point I remove the dry fit fingerboard and proceed with finishing the peghead.
17. Drill out tuner holes.
This is fairly easy if you use a drill press. The difficulty is to not cause the rather brittle ebony overlay to break out when drilling through. I drill from the back with a brad point drill, drilling only deep enough for the point of the drill to break through the surface of the peghead. Then I turn the peghead over and drill .through from the surface side.
Cut ledges for peghead binding.
My pegheads have a binding (to match the body) and a W/B/W purfling inside the binding, mitered at the corners. this entails a two step cut but is quite easy since the peghead is flat and the fingerboard is not yet glued in place.
Prepare and install peghead inlay as necessary.
These days I have my peghead logo ( an "h") cut for me by Tom Ellis, one of the main CNC cutters of pearl. For many years I cut my own inlay (or had one of my employees, Ms. Stevie Beck) cut it. This is a relatively simple matter using a small jewelers saw. Because this process is so often described on other web sites I will pretty much skip the process. The photos HERE on my site show how I do it.
Install peghead binding.
I bind all of my pegheads these days. I use a router to cut the appropriate ledges using the same or similar cutters to those used on the body. Because the peghead is small and flat it is relatively easy. I cut these ledges (and bind the peghead) before gluing on the fingerboard since I like my peghead binding to run slightly under the end of the fingerboard and it is very difficult to cut the ledge well if the fingerboard is in the way. It is important that the neck is exactly the same width as the fingerboard when cutting the binding ledges so that they will match up (see # 16 above). Another issue here is bending the binding. If you are using plastic binding this is not all that difficult, but wood binding must be pre - bent to the exact shape. I use a commercial bending iron for this and it works well.
Glue fingerboard to neck
The important issue here is making sure that the neck is flat when the fingerboard is glued on. I achieve this by clamping the board/neck combination to a very rigid very flat work piece. I use a piece of old iron I beam that I had flattened by a machinist. This tool is absolutely invaluable in our shop and this is the main use. I glue on the fingerboard straight since I already have a little back tension on the truss rod. The other possible solution is to make a caul which will glue up the neck with a slight amount of back bow and count on the string tension to bring it all straight. This is the method used by Jim Olson.
Trim excess wood from neck as necessary.
At this point we begin the final shaping of the neck. As the old joke says, you just cut away everything that doesn't look like a neck. I start by cutting off any of the neck that is wider than the fingerboard. This generally involves the band saw and the round end of the belt sander.
These days I do this with my spindle shaper and a jig which accurately cuts the thickness of the neck. Before I figured this out I used an old fashioned spokeshave - which is a tool designed to act as a plane on rounded surfaces. When really sharp these are a delightful tool to use.
Shape neck to correct profile.
My main tools for this are a spokeshave and a Nicholson # 50 rasp. This is one of the really old fashioned "woodworking" aspects of guitar building and while it is hard work I love it. To be successful you need to have a clear idea in your head of the shape you want (a V shape, a rounded shape, a flat shape, etc) and the willingness to work slow enough to avoid removing too much stock. As I get close to the final shape I find that my hand, and particularly my thumb, is the best tool to "feel" the neck and determine if the curves are smooth and fair and if the overall feel is good. I really love the tactile element of this part of the process.
Cut heel length to correct length and install heel cap.
With the fingerboard now installed it is easy to check to ensure that the heel length is exactly right. I try to have the heel cut so that the while piece just below the heel cap (which is generally ebony on my guitars) exactly coincides with the WBW purfling on the side of the guitar.
Sand neck to correct profile and to prepare for finishing.
Sanding is just another step in the process of shaping the neck. One "trick" that I use is to take a long (11") piece of 60 grit sandpaper and sand the shaft of the neck much like I was using a shoeshine rag. This really does a wonderful job of smoothing out any slight imperfections and making sure that the curves are smooth and fair. Then it is just a matter of sanding till it is smooth enough to finish. I sand to a 220 grit with at least one wipe down with a wet rag to raise the grain.
27. Fill ends of fret slots as necessary.
Sometimes the fret does not come to the bottom of the fret slot, leaving a small gap or hole. To get a good finish job this must be filled. I generally use stick shellac applied with a small hot spatula. Cyanoacrilate glue and ebony dust also works well.
Mask off playing surface of fingerboard as necessary.
Before starting the finishing process I mask off any area that should not get finished - here it will be the fingerboard playing surface, the underside of the fingerboard where it will glue to the top and the gluing surfaces of the dovetail.
Install handle on dovetail for spraying.
I have made a bunch of "handles" for holding the neck while spraying it. They are simply a "stick" with a female dovetail cut in one end that matches the dovetail on the neck. A simple friction fit is quite sufficient to hold the neck for this purpose.
Spray vinyl sealer.
The next steps are exactly the same as finishing the body so I will not repeat those descriptions.
Spray 4 coats of nitro lacquer.
Drop fill pits etc as necessary.
Wait about 1 week.
Sand lightly with 220 grit frecut paper.
Spray 3 coats of nitro lacquer.
Drop fill as necessary.
Sand to flat and smooth with 220.
Spray 2 coats of nitro lacquer.
Wait about 1 week.
Wet sand with 600 wet or dry paper to flat.
Wait a day.
Sand with 1000 wet or dry paper.
This website and all of its
content, text and images are copyright ©1997-2011 by Charles A. Hoffman.
All rights reserved.
This website and all of its content, text and images are copyright ©1997-2011 by Charles A. Hoffman. All rights reserved.
2219 East Franklin Ave.
Minneapolis, MN. 55404