Dave MacArthur
01-24-2008, 4:00 AM
Hi,
Someone in another thread was asking about inlaying into ebony, and I wanted to be able to link to this thread without taking over theirs. So I decided to post some pics I just took of my guitar that I built some years ago.
The guitar was designed and built completely by me, with some guidance from my father who had built two acoustic guitars, and was my first real woodworking project of my own. Prior to this, I was the "B Man" for my father's projects. This was a nice coming-of-age project that let me spend time with my Dad but do my own thing--kind of a "Woodworkers First Hunt" thing ;) It is styled after the classic "Les Paul Custom". Most of the guitar was built with hand tools, and it is highly embellished with inlays around the whole body and neck of abalone shell, and mother-of-pearl. I designed an internal wow and phase-shifter, which is installed in the back, and "active electronics" based on an article in Pop. Electronics, which pre-boost frequencies for tone control rather than filtering/cutting them out prior to the amp as most guitars do.
The body of the guitar was made from a large slab of walnut that had been hit by lightning and produced a burl. I acquired the 3" thick slab from a guy in Pennsylvania, probably up near Jim Becker though I can't remember exactly where now (I lived in Hockessin Delaware, across the PA border). He had a massive shop, and built scale models of various craft for the Navy for wind tunnel testing and water testing--very interesting.
I cut the body out so the line of figure in the wood would parallel the strings. You can see there is a color differential depending on what angle you look at it, sort of like a hologram--the wood is all the same color, but half the slab appears markedly lighter due to the grain when viewed at an angle.
The body was shaped using a router sled, and is convex (humped) in the middle, both in the top-bottom axis AND the front-back axis. It's hard to tell, but it's about 3/4" raised in the curve. I built a box to sit the body in with curved edges and ran the router back and forth on a slotted sled over the top, turned the slab 90 and modified the height, repeated. Finish shaped with sanding and rasps.
The neck is made out of walnut, and the head is also walnut. You can see in the closeup that there is a patterned inlay stripe--this is actually maple/walnut/cherry/walnut/maple. It provides structural strength and stability--I used long grain, but alternated each veneer on a slight bias, and used epoxy to laminate them all together straight through the neck. In a guitar, there must be an opposing force to keep the string tension from bowing the neck, and this is usually achieved by routing a curved slot under the fingerboard the length of the neck, inserting a curved metal rod, topping with another curved wooden filler, then emplacing the fingerboard. The rod is affixed to the head, and by tightening a bolt the neck/body interface you straighten the rod out a bit to provide a counteracting force to the strings. In an electric guitar the forces involved are much less than in an acoustic guitar due to lower tensions on the strings.
When I designed the guitar, I desired to have a much thinner neck than was normal, that is the thickness, to allow me to get full wrap-around with all fingers allowing faster scales etc., and to achieve this thinner neck I went with the epoxy cross laminated backbone, and an insert rod with much less bow than normal. The guitar is over twenty years old now, and I have had no problems, so I guess the design worked ;)
The neck and head were rough shaped on the bandsaw, then shaped using rasps, files, and sanding by hand.
The head piece has a veneer of walnut to match the darker body color. You can see at the top a mother-of-pearl scroll that I inlaid. I cut all the inlay pieces on a scroll saw/jig saw... can't remember the brand now. Originally I was planning on inlaying my initials into the scroll in ebony, then I was going to do it in Lord of the Rings "feanorian" script, then it was going to be lightning bolts...but each month my plans changed, and as you can see I never committed heh.
The fretboard is black ebony. In the closeup with the flash, it looks brownish, but it's pretty much solid black. I also decided to make the neck/fretboard less wide than normal, that is with strings more closely spaced, to again allow pinky/ring finger manipulations of the bass strings easily, which you can see. An interesting facet of musical instrument design theory is that the neck length is NOT a "standard" thing! You can essentially make your string length whatever you want! Each fret's position must be calculated based on it being a certain fraction of the total string's length--I was astounded when I learned this. So of course I had to lengthen the strings a wee bit more than normal, to provide wider fret spacing up in the high notes, to again allow cleaner fingering of high scales. The consistent tuning of a scale is achieved by tensioning the strings correctly.
Another interesting thing is that a well-made fretboard is curved in the same shape that high-tension electrical wires--you know, power lines-- hang in. Imagine a string vibrating, you can see that on both ends where the string is attached it doesn't move much, but in the middle it vibrates through a much larger arc. If the fretboard isn't curved to allow for this arc, then the string will "buzz" on the frets, or the board must be so far away from the high-note region of the string that it's difficult to finger the notes. By curving the fretboard to follow the string's oscillation path, you can make it much more smooth and comfortable to play. Each string is different too--the bass strings arc out a much wider path. I basically final shaped the fretboard with strings in place and tuned, measuring the gap all along the string when in motion to account for the frets. When you finger down on a higher-up fret, once again there must be enough gap that the string doesn't buzz on the next frets, but not so much gap that it's hard to play the next couple frets up with other fingers. Some of this curve can be pre-calculated, but with a custom length string like mine, I couldn't just use a template from a book. Once the frets are installed, there is probably another 20 hours of sanding and perfecting their height also.
Most electric guitars have very little if any curve to the fretboard, but I think this is more an economy move than anything--it's difficult to curve the frets well to fit the board. However, a slight curve makes for better playing IMO, so I did that also. Each fret wire was cut and curved to match the fingerboard. The slots were cut using a back saw and a jig for straightness.
All of the hardware is gold-plated. The machines are Schaler, and the pickups are DiMarzio humbucking. Can't remember who made the bridge. The nut up near the head is made from bone, which I believe I actually got from a birthday roast or similar... it smelled like hell shaping it!
The electronics of the guitar are noteworthy. Popular Electronics had an article in 1980 or so about "active electronics", which I used as the basis for the guitar. In most guitars, tonal control is achieved by creating a "filter", which is a capacitor hooked up to a variable potentiometer (resistor). Basically as you turn the knob, all frequencies above a certain changeable level are just stopped--they won't pass the capacitor. In this manner, the full range of frequencies passed on to the amplifier is chopped, producing tone control. The problem with this approach is that there are so many rich tones and effects that can be achieved at the amp, that it is almost a sin to build an oscillation making musical device, then just KILL a whole spectrum of frequencies and potential off as a rough-handed way to achieve tone control from the instrument. Instead, active electronics amplify frequencies to achieve tone control, leaving all the rich oscillations and side-tones still alive to reach the main amp.
Along with this active electronics, I ripped apart two common foot-pedal switches from the 70s/80s (wow and phase shift), and replicated their design on a circuit that would fit inside the guitar using the radio shack board etching kits. You can see a small silver toggle switch at the very back of the guitar--that is a 3 position switch that goes from normal to the other two effects. You can see the (scratched up) cover plate for the electronics in the back, where I have my name. Another really neat thing you can see there is a SHOTGUN PELLET! Someone had shot the tree, and upon machining the body slab I found this shotgun pellet in the wood! I liked it there, and left it in the back, where I have gotten countless hours of enjoyment thinking about that tree's life of being shot, hit by lightning, growing through ages of heat and cold, to end up making music and folk songs for my kids.
Probably the "best" aspect to the guitar is the complete surround of abalone shell. I had a box of 1"x1" abalone, about 1/16" thick. I marked each piece, and cut them out one by one to fit all the way around the body, around the neck. They were inlaid into a small rabbit, and held with clear epoxy. This was the hardest part of the guitar--the ends of each piece had to be angled to match the next one, and fit the curve. I shaped them on the scroll saw, then smoothed them each on a drum sander mounted in the drill press and by hand. At first it took like 3 blades per piece, but at the end I could do 8-10 per blade before breakage.
The fret markers on the fretboard are mother of pearl. I routed the neck out using a dremel tool with a little "router base" and a very fine spiral bit. The ebony was very brittle and tended to produce brittle fibers, like composite carbon fibers. On the edge of the fretboard when viewed from above (in the playing position), you can see I inlaid small brass fret markers. These are actually small wire posts from radio shack cut off ;) I liked the look, so went with brass instead of more abalone.
The finish is about 10 coats of polyurethane, rubbed out between each coat. I didn't actually polish the guitar up for the photos--originally I just took some so I could reply to a thread about inlaying brass in ebony. I may go back and polish it up and repost another pic, after all this typing! ;) I see in the flash/blow ups that there is some dust I should have wiped, and fingerprints.
Most of the work on the guitar was completed with hand tools, and it was all done at my father's house. I built most of the guitar my senior year of high school, and finished it my freshman/sophomore year at the AF Academy while on leave. I do recall that the table saw used was a Craftsman contractor, the bandsaw was a Rockwell 9", and the router was a PC. Despite having much nicer tools of my own now, I don't know that I've turned out anything better than this--I'm sure there's a lesson there, but I'm too busy shopping the Grizzly website to look for it just now ;)
Hope you enjoy this post--wish I had some pics of the build, but I wasn't digital back then. Next up: the instrument I replaced this one with, my bagpipes!
Someone in another thread was asking about inlaying into ebony, and I wanted to be able to link to this thread without taking over theirs. So I decided to post some pics I just took of my guitar that I built some years ago.
The guitar was designed and built completely by me, with some guidance from my father who had built two acoustic guitars, and was my first real woodworking project of my own. Prior to this, I was the "B Man" for my father's projects. This was a nice coming-of-age project that let me spend time with my Dad but do my own thing--kind of a "Woodworkers First Hunt" thing ;) It is styled after the classic "Les Paul Custom". Most of the guitar was built with hand tools, and it is highly embellished with inlays around the whole body and neck of abalone shell, and mother-of-pearl. I designed an internal wow and phase-shifter, which is installed in the back, and "active electronics" based on an article in Pop. Electronics, which pre-boost frequencies for tone control rather than filtering/cutting them out prior to the amp as most guitars do.
The body of the guitar was made from a large slab of walnut that had been hit by lightning and produced a burl. I acquired the 3" thick slab from a guy in Pennsylvania, probably up near Jim Becker though I can't remember exactly where now (I lived in Hockessin Delaware, across the PA border). He had a massive shop, and built scale models of various craft for the Navy for wind tunnel testing and water testing--very interesting.
I cut the body out so the line of figure in the wood would parallel the strings. You can see there is a color differential depending on what angle you look at it, sort of like a hologram--the wood is all the same color, but half the slab appears markedly lighter due to the grain when viewed at an angle.
The body was shaped using a router sled, and is convex (humped) in the middle, both in the top-bottom axis AND the front-back axis. It's hard to tell, but it's about 3/4" raised in the curve. I built a box to sit the body in with curved edges and ran the router back and forth on a slotted sled over the top, turned the slab 90 and modified the height, repeated. Finish shaped with sanding and rasps.
The neck is made out of walnut, and the head is also walnut. You can see in the closeup that there is a patterned inlay stripe--this is actually maple/walnut/cherry/walnut/maple. It provides structural strength and stability--I used long grain, but alternated each veneer on a slight bias, and used epoxy to laminate them all together straight through the neck. In a guitar, there must be an opposing force to keep the string tension from bowing the neck, and this is usually achieved by routing a curved slot under the fingerboard the length of the neck, inserting a curved metal rod, topping with another curved wooden filler, then emplacing the fingerboard. The rod is affixed to the head, and by tightening a bolt the neck/body interface you straighten the rod out a bit to provide a counteracting force to the strings. In an electric guitar the forces involved are much less than in an acoustic guitar due to lower tensions on the strings.
When I designed the guitar, I desired to have a much thinner neck than was normal, that is the thickness, to allow me to get full wrap-around with all fingers allowing faster scales etc., and to achieve this thinner neck I went with the epoxy cross laminated backbone, and an insert rod with much less bow than normal. The guitar is over twenty years old now, and I have had no problems, so I guess the design worked ;)
The neck and head were rough shaped on the bandsaw, then shaped using rasps, files, and sanding by hand.
The head piece has a veneer of walnut to match the darker body color. You can see at the top a mother-of-pearl scroll that I inlaid. I cut all the inlay pieces on a scroll saw/jig saw... can't remember the brand now. Originally I was planning on inlaying my initials into the scroll in ebony, then I was going to do it in Lord of the Rings "feanorian" script, then it was going to be lightning bolts...but each month my plans changed, and as you can see I never committed heh.
The fretboard is black ebony. In the closeup with the flash, it looks brownish, but it's pretty much solid black. I also decided to make the neck/fretboard less wide than normal, that is with strings more closely spaced, to again allow pinky/ring finger manipulations of the bass strings easily, which you can see. An interesting facet of musical instrument design theory is that the neck length is NOT a "standard" thing! You can essentially make your string length whatever you want! Each fret's position must be calculated based on it being a certain fraction of the total string's length--I was astounded when I learned this. So of course I had to lengthen the strings a wee bit more than normal, to provide wider fret spacing up in the high notes, to again allow cleaner fingering of high scales. The consistent tuning of a scale is achieved by tensioning the strings correctly.
Another interesting thing is that a well-made fretboard is curved in the same shape that high-tension electrical wires--you know, power lines-- hang in. Imagine a string vibrating, you can see that on both ends where the string is attached it doesn't move much, but in the middle it vibrates through a much larger arc. If the fretboard isn't curved to allow for this arc, then the string will "buzz" on the frets, or the board must be so far away from the high-note region of the string that it's difficult to finger the notes. By curving the fretboard to follow the string's oscillation path, you can make it much more smooth and comfortable to play. Each string is different too--the bass strings arc out a much wider path. I basically final shaped the fretboard with strings in place and tuned, measuring the gap all along the string when in motion to account for the frets. When you finger down on a higher-up fret, once again there must be enough gap that the string doesn't buzz on the next frets, but not so much gap that it's hard to play the next couple frets up with other fingers. Some of this curve can be pre-calculated, but with a custom length string like mine, I couldn't just use a template from a book. Once the frets are installed, there is probably another 20 hours of sanding and perfecting their height also.
Most electric guitars have very little if any curve to the fretboard, but I think this is more an economy move than anything--it's difficult to curve the frets well to fit the board. However, a slight curve makes for better playing IMO, so I did that also. Each fret wire was cut and curved to match the fingerboard. The slots were cut using a back saw and a jig for straightness.
All of the hardware is gold-plated. The machines are Schaler, and the pickups are DiMarzio humbucking. Can't remember who made the bridge. The nut up near the head is made from bone, which I believe I actually got from a birthday roast or similar... it smelled like hell shaping it!
The electronics of the guitar are noteworthy. Popular Electronics had an article in 1980 or so about "active electronics", which I used as the basis for the guitar. In most guitars, tonal control is achieved by creating a "filter", which is a capacitor hooked up to a variable potentiometer (resistor). Basically as you turn the knob, all frequencies above a certain changeable level are just stopped--they won't pass the capacitor. In this manner, the full range of frequencies passed on to the amplifier is chopped, producing tone control. The problem with this approach is that there are so many rich tones and effects that can be achieved at the amp, that it is almost a sin to build an oscillation making musical device, then just KILL a whole spectrum of frequencies and potential off as a rough-handed way to achieve tone control from the instrument. Instead, active electronics amplify frequencies to achieve tone control, leaving all the rich oscillations and side-tones still alive to reach the main amp.
Along with this active electronics, I ripped apart two common foot-pedal switches from the 70s/80s (wow and phase shift), and replicated their design on a circuit that would fit inside the guitar using the radio shack board etching kits. You can see a small silver toggle switch at the very back of the guitar--that is a 3 position switch that goes from normal to the other two effects. You can see the (scratched up) cover plate for the electronics in the back, where I have my name. Another really neat thing you can see there is a SHOTGUN PELLET! Someone had shot the tree, and upon machining the body slab I found this shotgun pellet in the wood! I liked it there, and left it in the back, where I have gotten countless hours of enjoyment thinking about that tree's life of being shot, hit by lightning, growing through ages of heat and cold, to end up making music and folk songs for my kids.
Probably the "best" aspect to the guitar is the complete surround of abalone shell. I had a box of 1"x1" abalone, about 1/16" thick. I marked each piece, and cut them out one by one to fit all the way around the body, around the neck. They were inlaid into a small rabbit, and held with clear epoxy. This was the hardest part of the guitar--the ends of each piece had to be angled to match the next one, and fit the curve. I shaped them on the scroll saw, then smoothed them each on a drum sander mounted in the drill press and by hand. At first it took like 3 blades per piece, but at the end I could do 8-10 per blade before breakage.
The fret markers on the fretboard are mother of pearl. I routed the neck out using a dremel tool with a little "router base" and a very fine spiral bit. The ebony was very brittle and tended to produce brittle fibers, like composite carbon fibers. On the edge of the fretboard when viewed from above (in the playing position), you can see I inlaid small brass fret markers. These are actually small wire posts from radio shack cut off ;) I liked the look, so went with brass instead of more abalone.
The finish is about 10 coats of polyurethane, rubbed out between each coat. I didn't actually polish the guitar up for the photos--originally I just took some so I could reply to a thread about inlaying brass in ebony. I may go back and polish it up and repost another pic, after all this typing! ;) I see in the flash/blow ups that there is some dust I should have wiped, and fingerprints.
Most of the work on the guitar was completed with hand tools, and it was all done at my father's house. I built most of the guitar my senior year of high school, and finished it my freshman/sophomore year at the AF Academy while on leave. I do recall that the table saw used was a Craftsman contractor, the bandsaw was a Rockwell 9", and the router was a PC. Despite having much nicer tools of my own now, I don't know that I've turned out anything better than this--I'm sure there's a lesson there, but I'm too busy shopping the Grizzly website to look for it just now ;)
Hope you enjoy this post--wish I had some pics of the build, but I wasn't digital back then. Next up: the instrument I replaced this one with, my bagpipes!