How to Build an Acoustic Guitar
Since there exists plenty of information and blog type details of first hand experiences in building an acoustic guitar, I thought I'd focus more on the difficulties I encountered as I built my own guitar. As with any new project I've attempted, each step along the way is unfamiliar to me and some steps are deserving of my apprehension, while others equally as worrisome turned out to be a piece of cake. This project is a learning experience. How well the guitar will play and sound, I will not know until some time after I have finished. Will I use the experience I've gained to build another? Not sure, but after I built my first wooden canoe, I built another and two kayaks, so I'll say ....maybe.
-- Getting Started --
The first task was to decide what to use for reference material. I chose a book entitled " Building Your Own Acoustic Guitar: Complete Instructions and Full-Size Plans" by Jonathan Kinkead. I selected that book after reading about a few others on Amazon but my purchase was rather impulsive. It walks the reader through building a style of guitar similar to the Martin OM(orchestra model), which is a smaller guitar with a more body. The book includes lots of photos and even full scale plans, which are handy, but, while sufficient, lacks information I need. For instance, the author thoroughly describes how to complete a certain step but does not go into the "why" so much. He doesn't go into alternate methods too much either, which because I'm too rebellious or don't have the tools needed, is something I would have liked to read. One other difficulty, the author is British. They way he describes some things and the words he uses make it a bit hard to interpret at times. The dimensions are all in metric and english, however the english dimensions are in very fine, hard for me to read, print. The book is sufficient and I used online resources also from blogs and "how-to-info" provided by Stewart-McDonald and other Luthier supply sources.
The next task, which was the source of some consternation, was to select the wood to use for the body of the guitar. The book recommends specific wood, Sitka Spruce for the top and Rosewood for the back and sides. I, being the rebel, didn't want to do that, so I chose different wood. There is a lot written about different tone woods and how they affect the sound of the guitar. Deviation from the normal popular varieties of tone woods is heresy to some makers while others consider it creativity. Once you think you want to deviate from the norm, deciding what wood to used can be a daunting task. Cost was a big consideration for me, some woods can be very expensive.
I chose Western Red "Sinker" Cedar for the top (or sound board as it is called) and Claro Walnut for the sides and back. I purchased both from suppliers on E-bay. The Cedar top is supposed to create a "warm" sound. I don't really know what that means but that didn't seem like a bad thing to me. "Sinker" means it came from a Cedar log salvaged from a lake or river bottom and is therefore, probably pretty old. That idea appealed to me. Claro Walnut is highly figured walnut from the American Northwest. Walnut in general is supposed to be similar to rosewood or mahogany. It is said to create a bright sound. I don't know what that means but "warm and bright" sounds pretty good to me. I also like the rich dark color of walnut and the fact that the wood I chose is not exotic or imported.
I paid about $30 for the Cedar top and about $75 for the Walnut sides and back. Depending on the type and grade of wood(A to AAAA) you can expect to pay from about $25 to a few hundred for the top and from about $60 to several hundred for the sides and back.
I felt satisfied that I got started and made some decisions, which is sometimes the most difficult thing when starting any new project. So at this point I had wood for the top, back and sides. I made other purchase which I will describe later on.
-- Making the Wood the "proper" Thickness --
Time to dive in. The sound board and back wood arrived, each in two pieces that needed to be joined together. It is desirable to minimize the visibility of the glue line, so the edge of the wood needed to be trimmed flat and even to make them fit tightly together. My book recommended using a block plane. I have a few block planes but they are dull and I've never really been very skilled at using them for the finer detailed work. Remove a lot of wood, yes, ok I'm good with that, but making edges perfectly flat, not in my skill set.
I used sand paper, clamped to a flat surface with a long right angle block of wood also clamped to that surface to complete this job. My thought was that if I ran the edge of each piece of wood back and forth on the sand paper and along the block of wood, the edge would end up flat. So I thought. The problem is in drawing the wood back and forth the I exerted uneven pressure on the wood. When I placed the edges of my wood pieces together, like they would be glued, and held them up to the light, I saw light coming though the joint. Not supposed to, if you have a perfect joint...so they say. I continued this process but still could make the joint "perfect". I resorted to sanding parts of the joint surfaces by hand until I got it good enough. I still saw faint light in parts of the joint but I knew I would not get it any better by continuing.
To clamp the wood pieces together I placed two long and square pieces of wood like a frame, on my flat surface(a 2X4 foot piece of 3/4" MDL) and held them in place with clamps. The distance between these was slightly less than the final distance across the two pieces being joined. When the edges of each piece of wood were placed against the frame and then the pieces pushed down at the middle joint there was sufficient pressure to hold them and squeeze out some of the Titebond Original glue. I placed some weight on top to the wood to keep it held down.
Once the glue was set after a day, it was time to make the sound board and back the proper thickness. My book suggested 2.5mm for the top and 3mm for the bottom, but it didn't tell me the consequences, difficulties or disadvantages of leaving them thicker or making them thinner. The book also suggested the way to make them wood the proper thickness would be to use a thickness planer or drum sander, two power tools I do not posses. It also said I could use a hand plane. That was something I was not about to try because...well you know my skill with a block plane, or lack thereof, and all my planes being too dull, and not wanting to try sharpening them...anyway.
I decided I could get the wood to the proper thickness by hand sanding. With rubber cement adhesive, I attached a piece of 80 grit sand paper on a flat piece of 8X10 inch plywood onto which I fastened a crude handle. I placed the wood to be sanded loosely between two long blocks of wood clamped on to my flat surface. At the ends of the wood, to keep it in place while I pushed and pulled the sanding block, I clamped a thin piece of wood on one end and aluminum yard stick on the other.
I began to run the sanding block back and forth across the wood, flipping the wood over and end to end occasionally to try and keep things uniform. I had to remove about 2 to 3 mm of thickness. It took a long time. The problem is in drawing the sanding block and forth the I exerted uneven pressure, resulting in some spots being slightly thinner than others. It wasn't terrible however and when I got close to the final dimensions I quit. I figured I'd leave some thickness for finish sanding. I used the same process to get the side wood to the "proper" thickness. I tried for less than 2mm since the sides needed bending and thin wood is easier to bend.
I used the plans that came with the book to trace half of the body shape onto a piece of cardboard then transferred that to a small sheet of 1/8 inch thick clear polycarbonate plastic to use as a template. Finding the glue joint in the top and bottom pieces of wood I used the template to trace the shape of the guitar body on the wood. Good thing the glue joint was not so perfect that I could not find the center line. Next I trimmed the wood to shape within a 1/4" of the line, with a band saw.
One more step complete. Apprehension was beginning to build thinking about the next steps in which, if I make an error to big, there would be no fixing.
-- Sound Hole, Rosette, Back Inlay Strip and Bracing --
Now it's getting serious. Time to cut a hole in the sound board. I searched online blogs and found how other people accomplished this. It seemed as if a high speed rotary tool and router bit would give me the best results. I looked at Dremel tools but after reading reviews I purchased the Black and Decker RTX-B at about 1/3 the cost of a Dremel.
To my purchase from Amazon I added the Dremel circle cutter attachment which is compatible with the B&D rotary tool.
I overlaid the paper plans on the top cedar sound board and marked the sound hole center by pressing a tack into the wood. Then I drilled a pilot hole slightly larger than the diameter of the circle cutter pivot pin. I did the same on a scrap piece of plywood and set up the attachment for the inside diameter of the rosewood and abalone rosette I purchased also from Amazon for $7. The book suggested inlaying thin purfling strips for the rosette, but I liked the looks of this one and thought it may be easier to inlay. After carving the inside diameter circle in the scrap wood I checked the depth and diameter and marked the circle cutter tool brace arm with a permanent marker. Then I cut the outside diameter and all the material in between it and the inside diameter, checked the fit of the inlay, marked the brace arm. I did the same for the sound hole diameter on the scrap wood. I now had 3 marks on the tool for the adjustments. Starting with the inside diameter, then the outside, then removing the in between wood, then cutting the sound hole, the top was ready to glue in the rosette. As it turned out, this was NOT the best way to do it. I was slightly off on the brace arm marks resulting in an outside diameter for the inlay which was slightly too large. I should have transferred the cuts to the sound board once I got the jig set up on scrap wood before moving it.
Well, my first of what was to be many mistakes. I added a fill around the rosette made up of super glue and walnut sanding dust, of which I had plenty by the way. I dabbed in super glue with the head of a pin then dropped a pinch of sanding dust on top then sanded it down immediately with 240 grit sand paper. I repeated the process until the gap was filled but still the fill looks a little coarse.
On the back, often there is a decorative strip inlayed to cover the seam. I thought I would inlay a strip of curly maple cut from the scrap pieces included as packing in order of the back and side wood. I wanted to put the thin black and white accent prufling strips along each side of the maple strip. I routed a channel for the maple strip. Perfect fit, looking good. Then I widened the channel for the accent strips. Success again, I thought. Here's the problem. The back was about 2.5-3mm thick and the strips were about 2mm + wide, so the inlay channel was shallow. The narrow accent strips just wouldn't stay in the shallow channel. Now I had a channel too wide. So I decided to make my own wider accent strips from Mulberry that I cut from my own trees a few years ago. It is a yellowish color. While widening the channel for the new strips I accidentally gouged the maple strip already glued in, but I kept on. With the new yellow Mulberry strips glued in, I leveled them and sanded the back, accidentally sanding completely thorough the maple and mulberry strips at one end. I was tempted to end the project then and there, but I filled the gouge and decide maybe to put a decal on the back over the missing portion of the accent strips...or just leave it for character.
Inside of an acoustic guitar is bracing for the top and bottom. I believe this is just to make the thin wood stronger but positioning of the bracing, its thickness and properties of the wood used can affect the sound of the guitar. My book called for Sitka spruce bracing. I didn't have Sitka Spruce and I wasn't going to purchase pre-cut Sitka Spruce bracing. I decide to use cedar, maybe this would add to the "warmth of the sound". I purchased a piece of 5/4 deck planking that looked like it had most of the grain running longitudinally. Then I followed the bracing shown in the plans to cut the pieces out of the plank with my table saw, trying to keep the grain longitudinal.
I traced out the bracing pattern on the back side of the top and bottom body pieces. Before gluing down the bracing I "strategically" removed some material, with the mini-drum sander bit for my rotary tool to allow the strength to remain but eliminate some of the sound deadening bulk. Sounds like I know what I'm doing right? I don't. The book also suggests slightly curving the bracing to give the top and back a slight arch. Now it didn't suggest a radius for that arch but it did say you could avoid this with the top and just make it flat, which I did. I did add a slight radius of about to the bottom bracing by making a template on a piece thin wood. I placed a metal ruler between a finishing nail driven into my flat MDF work board for the center then one about 9 inches to either end of the longest brace and 1/4" below the center nail. Next I flexed the metal ruler between the nails and traced the line onto the template wood and cut it on my band saw to transfer to the back bracing. I sanded bracing to the curved lines with a drum sanding bit in my drill press.
Clamping an gluing the bracing on the top required a menagerie of creative clamping methods and extensions and wedges. The back requires a slightly different menagerie since the bracing was slightly curved. All seemed to work out however, but I did end up removing more of the bracing bulk before gluing the whole body together, on two different occasions as I fondled and tapped on the sound board, listening for any hint of resonance.
Ok making some progress here, wondering if the cedar bracing will work out and if the wood is thin enough to make the body sing.
-- Making the Mold and Bending the Sides --
A fixture or mold is needed to hold the top, back and sides in place while gluing them together. The book I'm following suggests two methods of constructing the mold. One is to cut the shape of the body into several small, thick sheets of plywood or MDF and glue them together resulting in a heavy, and about 4 inch thick, fixture. The other method was to use two sheets of plywood separated by spacers. This was the method I chose. It also gave me the opportunity to use the Porter-Cable pneumatic finish nailer that my neighbor found in the garbage, and gave to me in need of repair.
I used a 3/4", 2 foot by 4 foot project panel from Home Depot and scrap pieces of 2X4 cut to size for spacers. This gave me a 24" X 24" mold, which was sliced in half then bolted together again with tab extensions. The guitar shape was a little uneven, but only slightly. It seemed to work out fine.
Now to bending the sides. I read that this can be a daunting step in any project, and indeed it was. It was suggested by the author and in many online writings to use a bending iron. This is basically a piece of tubing which is heated to several hundred degrees over which the thin side wood can be bent to the desired shape in small incremental steps using the shape in the mold as a guide to compare your bending progress against. First, any wood bending requires steam. This is achieved by soaking the wood for several hours in water then applying heat. The disadvantages I saw with using a bending iron, although the traditional method, were, 1. I didn't have one. I could make one. Several suggestions are available if you search online, some seem simple and clever, others, eh...I'm not so sure about. I could buy one for a couple hundred bucks. Ahhh, I don't think so. 2. Making the shape exact seemed difficult with this method. 3. Wood could easily get burnt, and I could easily get burnt.
I read lots online about this step, went back and forth on my decision before I actually did it. I had bent some wood successfully when building my canoes and kayaks using a different method. I decided, finally, to use a bending fixture made from the scrap pieces cut out of the mold plywood, which, just happened to be, the shape of the guitar body. I build the fixture with 2 pieces of the shaped plywood separated by spacers. Then I covered the bending surface with aluminum flashing. I also added a rounded piece of wood with eye-bolts and wing nuts, to help hold the side wood against the mold at the deeply curved waist in the body. To create the steam I built a small square box with a hole in it for steam to enter. Steam was created using an old coffee pot, with a small piece of copper pipe replacing the glass bubbler, which sat on a small camp stove. I read that when steaming walnut like I was using, sometimes the figuring in the wood becomes faded. I decided to do it anyway and even soaked the wood in water first.
Once the side to be bent was in the steam box for several minutes and there was an abundance of steam escaping from its joints, I slowly clamped the wood onto the mold. It bent easily. I was pleased as well as relieved. The next day I placed the first side in the mold fixture and clamped it in, then moved on to the next side. It went well also. I clamped it into the mold and let them dry for a few days.
All was good... except when I removed the sides from the mold, I found I had been too aggressive with the clamping and had slightly deformed one of the sides by causing a noticeable indentation from the wood I used along with the clamp to hold it in place. I tried re-wetting and clamping to smooth it out with only slight success.
Moving on. The next step was to trim the side to length and glue them together with the neck block and bottom block. The neck block was first trimmed to size. It came with the maple neck I purchased. More on that later. The bottom block came from a short length of 3/4" maple I purchase at Home Depot. These four pieces were glued then clamped in the mold. I now had something resembling a guitar body. The sides needed to be tapered with a gradual curve from the bottom towards the neck block, which is why it was trimmed earlier. I made a template from 1/8" hard board, with tapered spacers glued on, to fit around the outside of the body. I put pegs in holes on the inside of the mold to hold the sides up above the top surface, level with the template at one end and above the template on the neck end. Then I used a tiny block plane to remove side material to match the taper.
Lots of opportunity to make irreversible errors here but luckily the errors I made should only affect aesthetics and not function. My dream a beautiful hand crafted high end guitar was gradually diminishing to one of a hand-made guitar that functioned and had lots of "character".
The lower image is Willie Nelsons guitar "Trigger" by the way. It is a beat-up, autograph-covered Martin N-20 acoustic. At least I hope mine will sound OK and not end up as merely a decorative bunch of wood pieces glued together.
-- Kerfing Strips, Tail Piece Inlay and Fitting the Neck --
Kerfing strips a are long, slotted strips of wood, usually Mahonany or Basswood, that when glued onto the inside edges of the body sides, add more strength and rigidity. I could have made my own but I decided to purchase them from Stewart-MacDonald since they were relatively inexpensive($3.20 a piece for a 15 inch strip, I needed four). First I soaked the strips in water for several hours to make them more flexible. I then applied a generous bead of Titebond glue and placed them along the edges of one side of the body with about 1mm protruding. They were held in place with clothes pins clamped on about every 1/2 inch or so. After the glue dried, I usually give it a day, I flipped the body and did the same to the other side. The next day I trimmed the strips that protruded slightly so they were flat and flush with the edges of the sides. I also added some small vertical bracing strips to the side. Looked pretty good, I thought.
Kincades book has a chapter on making the neck and installing it. I glanced through this chapter and decided to do something different.Not surprising. I did not want to spend the time carving the neck and the dovetail joint it described. I purchased a pre-carved neck from Penta Guitar Works on e-bay. This guy has several styles, wood selections and scales available. I was impressed with the neck I received. It was a bolt on neck in Flame Maple (what I always call curly maple), included an routed truss rod channel, neck mounting block and large peg head suitable for almost any design.
Now I had to figure out how to attach the neck. I found a nice description here:
I ordered the exact parts(hex head bolts, washers, and inserts) described, from McMaster-Carr. I was ready to go, but this step was intimidating also because I needed to be precise. Not my forte. First, I cut away side panel wood covering the neck block mortise and dry fit the neck. A slight amount of sanding was required. Then I marked the position for two holes on the tenon of the neck. Then I marked the neck block, which was now attached to the body to line up with the holes I marked on the neck. I used a ruler. I found a problem. The online instructions specified bolt lengths for a block without mortise. Mine had a mortise so the bolts should have been shorter. I drilled the holes in the tenon deeper than specified. Problem solved. I did have to use my small drill press with the base turned backwards to get things to lined up, and to ensure my holes were square with the neck. This also required some creative clamping methods. I then drilled clearance holes for the bolts in the neck block and threaded the inserts into the holes in the neck tenon to about 1/16" below the surface. Time to try bolting on the neck. Perfect alignment, that almost never happens. Happy.
The truss rod is a long steel rod embedded in the neck that can be adjusted to increase or decrease tension on the neck which will move the stings closer or further away from the frets. If they are too close they can buzz while the instrument being played. If they are too far away it becomes difficult to play. Here again I fretted over what to do(pun intended). There are many fancy square, dual rod selections available from different suppliers. I chose a basic Gibson style rod with the adjustment nut meant to be at the peg head, and covered with a thin plate. This is common with electric guitars. My neck had a well in the peg head carved for this. The rod came longer than I need, threaded on one end and with one brass adjustment nut and one cylindrical steel nut. The rod was meant to be cut to length and threaded. The cylindrical nut was meant to be inlet into the upper end of the neck. Not what I did. I cut the rod and threaded it with a 10-32 thread and placed the cylindrical nut inside the guitar behind the neck block. My bracing inside the body was cut with a hole, designed for adjusting the tension from inside the body. Not what I'm going to do. I hope this works. I also cut a thin strip of scrap oak to fill in the neck channel over the truss rod. This will be added when I permanently mount the neck.
The tail end of the body where the sides meet creating a seam, is often covered with an inlayed strip of wood. I decided to use the yellowish Mulberry wood. I used my B&D rotary tool with a 1/8" router bit to carve an inlay channel. I used wooden strips as guides clamped to the body to get the triangular shape I wanted. Based on my attempt at routing the inlay strip for the back, I was a little more cautious this time. Turned out not too bad. Usually these inlays have accent strips around them, but remember... this is a basic guitar, just slightly more than colorful pieces of wood glued together.
Starting to look something like a guitar, and I starting to have thoughts, trying to keep them positive thoughts, about how it will sound.
-- Assembling the Body, Binding the Body --
Now comes the time to assemble the body, in other words glue the top and bottom to the sides. Both the top and bottom should be about 1/4" wider all the way around than the width sides. I started with the top. Laying the body sides onto the back of the soundboard and aligning its center line, I marked the places where the bracing came in contact with the kerfing. Then I marked the bracing where it extended outside of the body. I then cut away the bracing at the marks so it would fit inside of the guitar body and also cut away the kerfing where the bracing would contact it. I very carefully used my B&D rotary tool with a 1/8" router bit to gouge out clearance for the bracing ends. I used an Exacto knife to cut the bracing ends away. Dry fitting the top to the sides after this seemed ok, but I should have looked a lot closer. I dabbed some epoxy/sanding dust mixture in the gouged out areas of kefring because I wanted a good solid connection. A generous bead of Titebond was squeezed out onto the top to the kerfing and the sound board was pressed on, trying to keep the centerlines aligned. Creative clamping methods were applied but as it turns out, I should have spent more time making sure the kerfing was perfectly flat after I planed it and more time making sure the dry fit looked right. After some difficulty, sticking wedges in here and there, clamping where I could, using long pieces of wood stretched across, I managed to get the top glued down. There were some small gaps along parts of the edge because of the lack of flatness on the kerfing top.
I used the same process attaching the back, but this is even more of a blind fit and it has more of a curve than the soundboard. Instead of fussing with clamps I thought I came up with a different way to clamp the back on. I marked the outline of the body on a piece of 1/4" plywood and cut it about 1/2" inside of the line. Next I drilled clearance holes for 2-1/2" long drywall screws about an 2 inches apart all the way around it about an inch outside the line. Then I marked the holes on the mold surface and drilled smaller holes to drive the screws into. I glued on a piece of guitar shaped hardboard left over from my side tapering template. After applying glue and lining things up the best I could I screwed down my improvised clamping board. Seemed to work ok but the kerfing should have been planed at a slight upward angle rather than flat. I also noticed a gap between the neck block and the back. I probably did not account correctly for the curve of the back when I trimmed the neck block. I think I can fill the gap with a shim and glue.
As it turned out the curvature in the bracing did not create the slightly convex back like it should have, it was slightly concave. I don't know what happened. Oh well, moving on....
-- Binding the Body --
Next came a step that involved the router and potential damage to all my work so far if I did not proceed carefully. I needed to cut a channel along the edges of the soundboard and back for binding strips. I think these protect the edge of the guitar from dents and also add some decoration. I chose to use curly maple hardwood strips, plastic probably would have been easier to work with but I'm a big curly maple fan. In keeping with what has become the basic, plain Jane theme of my guitar, I chose not to put the thin prurfling accent striping on the back. I put them only on the front, which meant I needed a two step channel. I rigged up an adjustable guide, made from scrap wood, for my hand held router. I thought about it, tried to visualized the process and I kept having these disastrous scenes running through my mind, but I was ready.
First I had to trim the overlap left on the top and back. I decided to cut most off with a band saw then finish with a flush cut router bit. While trimming with the band saw, the side was accidentally gouged with the teeth of the blade in one small spot. I filled it with a small amount of epoxy and walnut sanding dust.
The night before I attempted to cut the channels, I was talking to my neighbor and ended up borrowing his hand held trim router. A complete last minute change in strategy. It had a roller bearing guide and some fine adjustment capability. I set it up, tried it on scrap and 10 minutes later had the channels routed. Another worry behind me.
The maple strips had been soaking in water in the bath tub all night and now I was ready to glue them in. I started with the simpler(no accent stripe) back. Applying a bead of glue to the channel and I pressed in the maple strip and held it in place with tape, dabbing off excess glue as I went. I added more tape to areas that looked like they needed it. Once that was done I flipped over the body and started on the front. Going pretty smoothly so far. When I got to the highly curved waist area, my thin maple strip broke. Not having another I proceed and used lots of pressure and tape to hold the broken pieces in place. After the glue dried overnight I took off the tape and discovered some problems. First the channel was not quite deep enough requiring more sanding of the strip to make it flush. I think the wood swelled more than I expected after soaking and perhaps the depth of the channel was not quite enough in some spots. Second the broken pieces were not seated very tightly in the channel, leaving a slight gap between the strip and body. I plan to fill with glue and sanding dust and keep moving on.
-- Preparing the neck --
The butt of the neck extended past the body so it needed to be trimmed. I thought I'd make a decorative cap from 3 contrasting pieces of wood, Mulberry, KOA, and Maple. I cut the neck butt to length then traced its shape onto the 3 pieces of wood. They were cut out with a band saw and glued to the butt. It was difficult to get them lined up since the glue was slippery. When it was time to trim and sand the pieces I found the cut I made on the neck butt was crooked. Do-over. This time I glued the 3 decorative pieced together first.
Next, I laid out the locations of the tuning pegs on the peg head. I made a paper template from my plans and checked the distance of the hole locations from the side of the peg head with a ruler. Then I drilled small pilot holes. The peg head was extra long so I cut it shorter and added a bit of decorative contour top the top.
After some fine tuning, pun intended, by removing a little wood with sandpaper to make the neck fit as flush as possible to the body, I removed it and applied some stain. I use Behlen American Walnut Solar-Lux NGR(non grain raising) stain. I first did a little finish sanding with 240 grit until I was tired of sanding, the bushed on one coat of stain, leaving the fret board area unstained. After it dried I sanded again with 240 grit and brushed on another coat. When the 2nd coat dried I rubbed down the neck with steel wool.
Once satisfied with the appearance I drilled out the pilot holes to accept the Gotoh Chrome machine heads. I measured their diameter with micrometers and found a drill bit close to the same size, which was 3/8" I drilled a test hole first in scrap wood to make sure it would not be to large. I used a reamer tool to make the tuners fit snuggly into the holes. Another problem. The neck I purchase had a little curve at the bottom of the backside of the peg head causing the lowest set of tuners to not lay flat. I had to gouge out clearance, then re-sand and re-stain the area.
I jumped the gun a little in staining the neck now. I had to re-sand and stain when I created the inlay (next). I also found that when I test fit the nut I had purchased the neck was a tad too wide. More re-sanding and re-staining. Also as I would discover later the holes for the tuners were slightly off center on one side.
-- Peg head inlay --
I had some room left at the top of the peg head. Most guitars have the makers logo or some custom guitars have the makers name. I thought about inlaying my initials, but, since this is my first build and I’ve screwed up more than just a few things already, I wasn’t sure I was ready to sign my name to it. I decided to make a decorative inlay, kind of a star or cross shape out of three different types of wood.
First I drew it out on paper then colored in the different areas of the inlay. I liked it so I cut out each little piece and glued it to some scrap wood that happened to be all similar in thickness. Once the glue dried I cut out each piece on my band saw, then sanded to the “precise” shape. I laid out the pieces on a sheet of card stock then glued them in place, making sure to use plenty of glue where the pieces met.
I cut out a rectangle around the inlay then glued it to a block of wood. My intention was to sand down the inlay so that all the different pieces were the same thickness. I rubbed the block with the inlay attached on my large sanding block that was held in a vise. This worked pretty good.
I now had the inlay shaped like a star, or cross if you prefer, and I traced its outline on the peg head. Next I used a small chisel to cut, and scrape and finesse the wood out of the peg head where the inlay would go. After many trial fits and more scraping I finally glued the inlay in place and slightly above the surface of the peg head. I mixed some graphite powder with Titebond glue then clamped the inlay in place. I sanded it level with the peg head surface then re-stained the areas of the peg had that need it. I finished it off with steel wool.
It wasn't the perfect fit I wanted, some tiny gaps still existed, but I did my best to fill them and moved on.
-- Fret Board --
Building the fret board became a time consuming task. I needed to make a few decisions before I started. Did I want to buy a blank piece of rosewood, cut the slots and radius the surface myself or purchase a pre-slotted board with a radius? I decided to purchase. By the way the radius on the surface is supposed to make the guitar a little easier to play, so a flat fret board probably would have worked. Second decision, did I want to put and edge binding on the board? Yes, I think it looks better, but makes inserting the fret wire a little more difficult. Third decision, did I want to attach the fret board to the neck before or after installing the fret wires. I chose after, because I wanted to use my drill press as a McGuivered fret wire press and I need the board to be flat. More on that later.
The first thing to do was to cut the fret board to match the neck profile. I laid it on the neck leaving a little space for the nut, then clamped it to the neck, just eye balling the fret slots for perpendicularity. I then traced the neck on the back of the board and also the sound hole arc. I decided to make the bottom of the fret board near the sound hole have a slight arc. I guess that was a fourth decision. I then cut the fret board slight outside the marks with a bands saw. I used a small hand plane to clean up the edges.
Next I cut some maple for the side binding out of some scrap that came with my guitar back and side wood order. It was cut slightly wider than the thickness of the fret board. I then marked its thickness on the back of the fret board and use a plane to remove additional rosewood to make room for the binding. I thought of using a trim router to do this but decided to go with caution and did it using a plane and sandpaper. A fifth decision. The maple binding was then glued and clamped to the fret board, sides first, then the little curved piece at the end of the board near the sound hole. I had to resort to some more creative clamping. After the glue set I leveled the binding using sand paper.
Since I did not attach the fret board to the neck needed to clamp it to the neck and make it fit flush the best I could. This meant that I sanded off some off the stain. I noticed that the binding was getting sanded thinner in some spots than other. I tried to correct that but suspect more careful sanding will be needed to make it flush once I glue the fret board down.
I used a ¼” Fortsener bit to make relief for the Abalone fret dots. I tested the fit of the dot in a drilled out cavity first, then just drilled out each hole with my drill press to a depth that left a bit of the dot protruding. I drilled then tested, then drilled more, and tested, then more if needed for each dot. I glued the dots in place with super glue, a little too much super glue, then sanded them flush once the glue set. I used the same method for the side dots except I used an ordinary drill bit and just estimated the depth I needed, then sanded them flush once the super glue set.
I made a tool to use in my drill press for a method to press in the fret wire. It was just a ¾” wide piece of scrap Ash with a ¼” bolt on one side, head cut off of course. I marked a 16 inch radius curve on the little piece of Ash by using the 16” radius sanding block I purchase from Stewart-MacDonald Luthier supply. Then I use the drum sanding bit to take off the wood under the line. For each piece of fret wire I cut the length with a 1/8” to spare on each side of the fret board. Then with a dremel grinder and small file I removed the barbed portion on the underside of the wire so that the edges would lay over the side binding. Working on 2 fret slots at I time I use a small square file to give each slot a slight bevel then tapped the wire down with a hammer and block of wood just enough to hold it in place. I finished pressing it in with my rigged drill press. I also used a small piece of aluminum flashing between the wood pressing jig and the fret wire. Not sure why, just seemed like a good idea.
Once all the frets were pressed in, I trimmed the edges with wire cutters then filed them flush with the fret board binding. Since the frets are only held in the slots by the barbs, there is a slight gap left in the slot. I wicked super glue into the slots using whip tips which I purchased from Stew-Mac. These handy little tips slide right onto the bottle tip. I used some paste wax on each side of the fret wire to keep from slopping super glue onto the wood. This turned out to be a mess. The paste wax dried white, leaving white residue in the wood grain, and I slopped super glue on the wood anyway.
-- attaching the fret board --
First the slot that contains the truss rod needs to be filled. I use strip of oak, because I had a thin piece laying around. I routed a cove on one side and filled it with silicone sealant. Just a small bead, to keep the steel rod from vibrating. I the smeared glue on the side of the strip and clamped it in place. Once the glue was dry I planed and sanded the oak strip flush with the neck surface.
Mistake number ??. I should have waited to place the small nail head that keep the fret board from sliding around I needed to do some minor sanding to make the body surface perfectly flush with the neck surface and the nail head prevented that. As I result I have a slight gap between the fret board and the neck and body in that area.
I smeared glue on the neck surface and a little on the sound board (top) where the fret board would lay then clamped down the neck, wiping off the squeezed out glue with a wet paper towel as I went. I needed to use a C-clamp to attach the fret board to the body, since there is a slight bend required due to the set back angle of the neck. I hope the strings will clear the frets in this area. After the glue dried I found the top of the fret board had slipped sideways slightly, even though I tried to prevent this. I'll need to do some sanding and stain touch up.
-- truss rod adjuster cover --
Like I mentioned earlier, the tension adjustment for the truss rod on my guitar is located on the peg head....so it needs a cover. I made one from the scrap wood I had around by routing a shallow channel in the base wood and filling it with contrasting wood. It is a simple shape but a bit over sized. I had some difficulty making the adjuster nut flush or below the surface so the the cover would lay flat. I had to grind down the metal washer to a smaller size and also gouge out some wood to make the nut bear against a flat surface so as not to pull the rod up.
-- pick guard --
I decided to take a little side trip so to speak, and made a pick guard. I had a piece of scrap walnut with interesting figure in the grain so I used that. I first made a paper template and set it on the guitar to see how it looked. Next I sanded the scrap walnut to about 1/16" in thickness, it was already pretty close. Then I traced the shape of the paper template onto the wood and cut it out with a band saw. With a little sanding, the rough edges disppeared and a little more sanding made it fit the sound hole circle. I will attach it after finishing....but during the finishing the pick guard dropped on the floor and chipped the pointy end a little. I sanded it down but now it is slightly off the circle at the pointed end.
-- Attaching the bridge --
Attaching the bridge is probably one of the most important steps to get right in the entire build. The distance from the nut has to be precise to get the proper intonation. The centering has to be accurate so that the strings are spread evenly across the fret board. Here is where things started to fall apart for me. You may think, dude, they already fell apart.
I purchased a premade rosewood bridge, pins and saddle on Amazon. First I laid the bridge on the sound board with the saddle in place and held a string from the nut to the saddle to check the action height (distance the string set above the frets) UGH!!! The string was bottoming out on the frets. This would be un-playable. I realized the neck angle was too sharp. To adjust for this I did 2 things. First I shimmed the neck where it joins the body, decreasing the angle. I use walnut sanding dust and super glue to fill any gaps. Next I added a walnut layer to the bottom of the bridge to raise it about 1/16 inch.
I first placed a piece of blue painters tape on the sound board where the bridge would sit, and laid the bridge on top of it. Very carefully I measured the distance from the nut to the edge of the bridge. I need 25.4 inches (25-3/8 = 25.375). I used a length of braided fishing line strung from the nut to the bridge pin of the low E and high e strings to find the centering. Then I taped it down and cut the underneath tape to shape for masking the wood during the lacquer application. I was ready to apply the finish, I’ll discuss problems with the bridge location later.
-- Finishing --
Where I had sand though issues on the back with the center strip I applied some decorative stickers that are meant to be used on fret boards to try and hide the flaw a little. I applied finish over these.
I decided to use Behlen stringed instrument lacquer in aerosol spray cans. It was recommended to apply at low humidity and temperatures between 60 and 80F. The fumes from this stuff are hazardous and very volatile. I used a respirator mask and goggles when applying. Since this it was February when I came to this step I built a small spray booth in my garage from spare plywood and plastic sheeting in which I placed an electric heater and light. It is also recommended that 10 coats of lacquer is applied, with light sanding between each coat. I applied 4 coats of Behlen vinyl sealer first with light sanding after the first two coats. I then applied 7 coats of lacquer with light sanding between every 3 coats. I waited a half hour between coats and a day between every three coats before sanding.
After letting the finish harden for a week I wet sanded the top with 1000 grit paper and water with a little Murphys Oil soap added to the water the paper soaked in overnight. I only did this to the top. I preferred an more satin finish for the sides and back so I just lightly rubbed those surfaces with steel wool. After wiping the water from the top I used Turtle wax rubbing compound from an auto supply store to polish the finish. I polished by hand with a cotton rag then again later with a wool buffing bad in a drill. The finish looked OK but, sort of crude. Remember I was shooting for that Willie Nelson look.
-- Back to attaching the bridge --
When I laid the bridge over the masking tape I rechecked the distance from the nut, but this time I considered the compensation. The saddle is set at an angle for compensation and it’s distance from the nut should be 2mm longer than the scale length(25.4) on the high e string and 6mm on the low E string. I had measured the distance to the edge of the bridge. Unfortunately the saddle was more than 2mm from the edge at the high e string. This meant I need to slide the bridge up exposing a not too narrow strip of unfinished bare wood. Also the bridge mask was slightly crooked and shifted slightly off center. Darn! Darn! Darn!
I made the adjustments measuring from the nut to the saddle this time, then drilled 3/16 holes in. holes for the end pins to hold it in place while I glued it down. I carved the shape of the bridge top using a drill press sanding drum in a small block of wood, and drilled clearance holes for the pins. I used this with a little padding to help clamp the bridge down during gluing. I straddled the guitar body with a longer piece of wood and clamped the edges to the guitar body, pressing down on the bridge block.
Now back to touching up the finish to cover the expose bare wood. Disaster strikes. I ended up with runs and discoloration and even a gouge from a dremel buffing wheel near the bridge area. The more I tried to fix it the worse it looked. I think some more stickers are in order.
-- Final Steps --
I oiled the fret board with Old English Lemon oil, 2 coats, and one coat on the bridge, then rubbed off the excess with paper towel. I attached the pick guard with double sided 3M adhesive. I installed the truss rod end cover, at little off center of course. When I installed the tuners I found my holes to be slightly off. Too late to fix that. Also because I put the tuners too close the bottom of the peg head they needed to be installed upside down, which means to tighten the stings the turner need to be turned the opposite direction from traditional. Ok I can live with that, actually I have to live with all the mistakes.
It turned out that the string tension bent the neck slightly raising the action. I probably didn't need to raise the bridge as much as I did but I definitely need to shim the neck like I did. I decided to leave the action a little high until everything settle. It's not too bad, just makes the thing a little more difficult to play.
Now comes the moment of truth, stringing the guitar and hoping it sounds ok. I almost didn’t want to do this because I thought maybe it would sound dull. I used Martin medium strings. After I tuned it an strummed it I was amazed at how it sounded. It had a rich sound(kind of warm an bright I guess) with lots of sustain. I checked all the stings down to the body, no buzzing. This guitar may be a little rough and ugly but is sounds beautiful to me.
I am happy.
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