My name is Michael Greenfield and I am a guitar maker. Welcome to my workshop. My clients are artists, collectors and those who deserve the very best. They consult with me to address their musical needs and select options and features in order for me to make personalized musical instruments, and functional works of art. This documentary captures the journey, the process and the actual work in progress – glue smudges, ebony dust and all.
What you're about to see took place over the period of four to five months. We're going to start bending sides, to form a rimset. I use a laminated rimset which means I take pieces of wood, sand them very thin to make veneers out of them and glue a whole bunch of them together. It makes a more rigid structure. So, we're going to add a little bit of water to this and wrap it in paper. The paper just keeps everything clean. I have these silicone rubber blankets, and one of them has a thermal couple on it, which is basically a thermometer. It gets plugged into these controllers. These controllers are programmed to ramp up to – in my case – 250° F, for one minute. Then it will ramp down to 190° F, and it will hold it there for half an hour. Then it will turn off and cool to room temperature. You can see even from the weight of the clamp as it starts to heat up, you can see the wood starting to sag. The heat will plasticize the natural resins that occur in the wood and allow it to bend.
Then when it cools off again, those resins will resolidify and hold the piece in place. I just sit and watch the numbers, and smell the wood. It's been a few hours, everything has cooled to room temperature. You can see some of the resin that has come out of it. This is Julien, my apprentice and he is going to be installing the linings on this rimset. The linings are these little bendy pieces of woods that glued to the sides of the laminated rimset to increase the gluing surface so that the top and back will have more to stick to. Julien is bending the linings on this hot pipe with a damp paper towel on it to create steam and help the wood become more plastic and bend. While the linings themselves are fabricated with those little cuts to make it easy to bend it makes for a cleaner, more precise fit when we use heat to help form the part.
So this is a really beautiful set of moon harvested alpine spruce. What they'll do is fell a tree, find the straightest, most beautiful part of the log, split that part of the log in half split it into quarters, and then wedges. They orientate that onto the saw so all the grain is vertical – these consecutive slices are opened up like a book – which is referred to as bookmatching.
So these two consecutive slices which were numbered by the sawyer make up one guitar top. That's pretty common. It's very stiff and light – it makes for great guitars. You can hear it already. It's making music – all by itself. Ok! Let's turn this into a guitar top. So we just cleaned this up – it's easier for me to see and work with it. This is what we refer to as a pitch pocket – the natural resin that occures in the wood. I have it on this side as well. So, I want to make sure this falls outside of the guitar outline. This is absolutly not a problem, it's completely outside of the outline of the guitar.
And this one is also outside the outline of the guitar. So I'm good. If this pitch pocket occured somewhere else in the set of wood, I would of haved to reject it. Which is unfortunate but, it's just the way it goes. Let's take a little hot hide glue. That's it! We'll come back in a few hours and see how we did. What I'm doing here is removing excess weight from the X-brace.
By retaining the full height of the brace, I keep much of it's structural integrity And by pyramiding it towards the top, I'm removing – I don't know what percentage – but quite a bit of it's weight. So it makes a for a strong and light brace. It's all about making a responsive guitar. I remove mass to get the system as effecient as possible, but without going to far – which will result in a weak voice or at worst, structural failure. This is just a quick rough sanding, certainly not finished. So this is hide glue – animal glue – it's gelatin.
I'm going to put this on to heat up now, it will be ready in about ten minutes. This thing is referred to as a Go-Bar Deck, and it's a very ancient way of clamping things. My understanding is that it was developped thousands of years ago in ancient China and they used bamboo sticks. This is fiberglass sail batten, PVC plastic – that advantage to this is it has a memory. It always go back to zero. If you use wood, over a period of time it starts to distort and bend. It's not the end of the world but you have to replace the sticks. I never replace these sticks, these sticks are over twenty years old. I'm going to sign the sound board, I sign every single one. This one is going to one of my agents in Europe. It's just a generic signature, so this is what happens. This is the 5th month of 2016, and now we're going to put it on the guitar. You know, the challenge is to keep – as with everything else about the guitar – to keep the inside of the guitar as clean as possible.
So, it's like getting the perfect amount of glue on so you don't have a lot of squeeze out to clean up – but so that the guitar stays together and doesn't fall apart. We'll come back in 15 minutes and check the squeeze out. Now is the time where the glue is still soft enough, I can clean it out with a toothpick or something. But it's good! It's clean. *taps on sound board* That will take some work later.
This one is number 268. I use handmade paper because it's a handmade guitar, why not use handmade paper? And we make them ourselves. There it is, one Greenfield Guitars label. Let's go glue it on. We have the sound board, we have the back we have the rimset. We're at a stage where these bodies have been closed and it's starting to look like a guitar. It's a vacuum that will hold the guitar in any number of positions and free it up for me to work on the sides. So this is ready for the next step, I'm going to check for flatness and round. This is just the remanence of that glue that we used to make the rimsets earlier when we were laminating. This will all get sanded out dead flat before we go to finish sand – I just don't want to remove any more material that absolutly necessary at this early stage.
This is a piece of Honduran Mahogany. I bought enough of it for hopefully the rest of my career which would be awesome because it's getting exceedingly difficult to find in general, and of this quality and size in specific. Just to give you an idea… The ceilings in this workshop are 12 feet tall, and these boards were 17 feet long. You just don't find lumber – these sizes – that frequently anymore. Here is a piece that was sawn out of one of those boards and prepared closer to the size I need in order to make necks. The other material has been used to make internal blocks, other various structures. This is just a little universal template I made and it accomodates all of my various neck lengths that I use in the making of the guitars. So I'm just going to lay this out on the board and then we'll take it over to the bandsaw. Mahogany is a reasonably light and incredibly stable wood, which makes it such a great neck wood.
I'm cutting this out and this is going to sit on a shelf for probably a year to 18 months. Even though this wood is very old and it's already been in my shop for several years – everytime you cut wood you release internal stresses and the wood will move. So when I build my necks, it's usually over a period of many months and sometimes years. Really nicely quarter sawn, straight grain, old growth, Hunduran Mahogany. Step one is we're going to trough this surface up which is where eventually the finger board is going to get glued on. It's this ongoing process of making things flat and straight, letting it move, releasing stresses.
I'm just going to cut a slot in these to install the truss rod. This is a tool called a router plane, and it's just going to make sure I have nice clean even depth at the bottom of my slots. That's good. I'm going to establish the geometry for the neck. So we now have a clean, flat surface for a perfect glue joint. Boom. Even with no glue, you can hardly see the glue joint. You can't. That's why all that orienting and matching the blocks from the same board of wood, it pays off at this stage a couple years later once you prepare the joint. Just clean up the squeeze-out, and we're done. Okay, we're going to cut a fingerboard.
This is my old, old, old table saw that has been relegated to this one task at this point. This is a fixture I made 25 years ago. Another one of my temporary fixtures that just works fine so I'm still using it. Here's a piece of ebony. This comes from Cameroon. It's been brought to thickest for one of concert classical guitars, model C1. These are fret-slotting templates that are available at various luthierie supply stores.
There it is: twenty slots. All we have to do now is cut out the taper, the correct nut width, and this will get glued onto a neck a little bit later. Julien is now installing the purflings. These are a composite laminate of wood veneers that have been dyed and sliced into thin strips. They're for aesthetic purposes only. Unlike the purflings, which are mainly aesthetic, the bindings actually are installed to protect the joint between the soundboard and the rim set, or the back and the rim set, in case the guitar were to fall, or to take some kind of shock or impact. So, what this contraption is doing is: it's establishing the geometry between the neck and the body in three planes; in the vertical off the soundboard, which is going to establish the playability and the string height; left to right on the center line, which speaks for itself; also to make sure the neck goes down parallel to the top, because you don't want the neck to go askew.
Because of the dial indicator and the mechanics of this fixture, I can dial in the neck geometry to within one-thousandth of an inch. So, for the player, it's exceptional. So, this is a truss rod, and what it does is: it's job is to counter the pull of the strings to keep the neck straight. So, this gets installed up against this little block of wood, which keeps it from moving backwards, and I'm going put in a mahogany filler strip on the top, which will help prevent any buzz.
I'm just mixing up some marine-grade apoxy to glue the fingerboards on the necks now that everything has been prepared. And the reason I use apoxy as opposed to traditional hide glue — the animal glue that we used earlier — or even some of the other polyurethane resin glues, is they contain water. We've gone through this entire process of drying things out, getting them straight and level– if you add water to wood, the wood moves. So, I try and use non-water-based glues in the neck to keep things from moving around. So, the neck has now been rough carved, the majority of the material removed, so any movement that's happened in the neck, it's pretty much this is where it's going to live.
This dial indicator is showing me there is about two or three thousandths of an inch of what we call back bow, which is a hump in the neck, and which is totally normal because we've removed wood from this surface and my job is now going to be to flatten this out in a straight plane from the nut to the bridge while maintaining my compound radius of my fret board. Down here, I'm about minus half a thousandth. Here, I'm about plus half a thousandth. Here, I'm reading zero. Here, it's half a thousandth, so that needs a little more work. This sandpaper is at a fine enough grit now that it's not going to change the geometry of the fingerboard or its radius. So as you see, we're moving across the entire fret board. That's pretty much dead flat. Perfect fret work and neck geometry is a big deal. With hand tools to get it within 5/10's, it's more than acceptable. So, I buy fret wire in large rolls like. This particular comes from Germany. It's really super high-quality stuff, and this gold colour: it's really a copper-titanium alloy, or at least that's my understanding of what it is; and it's much hard than the conventional nickel-silver fret wire that we've been using for…
The last sixty years? Maybe seventy years? So, it lasts longer. As you can see becuase of the binding on the fingerboard, the fret can't go all the way through like on some of the older guitars; so I have to cut the tang, this T-part of the fret, to fit exactly into the slot. So, I use this little tool, and then each fret will be cut specifically for a slot, and I have to keep them in order. One side is plastic, one side is brass. Both of which are softer than the fret material, so that way when I'm hammering, I don't deform the frets. Okay, so everything appears to be really well seated. Now, I just want to see if there are any high frets at this point. If there was a high fret anywhere, I would feel it and hear it rocking. So now that the frets are in this neck before we finish carving it and do the final fitting of it, I just need to open up what will become the nut slot. So, I got this little fixture that I made, and what it does is: it's got the correct angle for the angle of the peg head, where the tuners go, so the nut sits in a parallel slot.
This little gauge block is the same thickness as my nut. So now I'm making the cut! That tool is set to stop just short of the bottom, as you can see. I'm just going to clean this up a little bit with a chisel. And that's it. One nut slot. I'm going to glue a heel cap on the end of the heel, which is this part of the neck down here. If there are any adjustments to be made to the geometry, that's when it will happen.
And it is exactly on the center line. Now that the frets are in it, it needs to be increased a little bit, but I will do that after I put the heel cap on. Now I'm going to transfer these little tick marks that I made to the neck, and I use the protractor to set the angle that will match the taper of the back, so when you look at the finished instrument, all the lines flow together naturally. Okay, so I'm going to make sure everything is fitting snug, which it is. Let's put some glue on this. I'm doing two things now: I'm matching the fit of this piece of mahogany to this piece of mahogany, so you get a super clean, super sharp line, and at this end, I am increasing the pitch of the neck ever so slightly.
Doesn't take much. The neck angle is a real big deal. Beside the obvious ease of playability and comfort for the player, it's a key component in how the string energy is transferred to the soundboard, and how the whole system works. So if you get it right, you'll have a really comfortable instrument to play that's super responsive. When I make my bridges, I drill these two little holes in them, and what they allow me to do is to put the bridge exactly where it needs to be now. Drilled those two holes in the soundboard, so that after I mask and remove the tape I can just put the bridge back in the right place without disturbing the finish, and everything will be perfectly intonated. So, it should be somewhere around here. Hopefully, it won't move. So now that this is in the right place, I'm still going to check it one more time, because it's that important. If you don't put it in the right place, you have to take the top off and go again. Ask me how I know.
We're basically at finish sanding now. The guitar has been rough-sanded to a high grit, everything has been flattened, everything is smooth, round. There are no little wavy sections. So now I'm going to bring it up to the final coarseness, or fineness, of sandpaper before it goes into the finish room. All of my final sanding I do by hand, inline with the grain. I'm just going to mask off the area of the soundboard, where the bridge is going to sit and where the fingerboard is going to be glue down, because you need to glue to wood — you can't glue to finish. With clean hands, I put down this piece of tape, which is really, really thin. It's about the same thickness as the finish. I have these little templates that I use for masking off the instrument. I have a surgical scalpel with a fresh blade, and I'm just going to very carefully trim the mask. Okay, so this guitar has had its first session of finish applied to it.
It's what we refer to as the base coat. So, most of this finish is going to get sanded off. Right now, everything is shiny, and you'll see as we sand it, the shiny goes away, but sometimes you'll see little shiny spots. And the shiny spot represents a low area in the finish, so I have bring all of this surface down to a point where there are no more shiny spots; and that means everything is flat and level.
See, I don't know if you could see, but there's like still a little shiny spot. So, that's a low spot. We're going to take off all the masking tape we put on a few weeks ago before this went into finish, so that we re-expose the wood and I have a good surface to glue to. We're gonna attach the neck.
It doesn't have to be hot. You just want to take the chill off of it, so that the glue doesn't gel before I'm ready. Here we have a bridge that we made a couple weeks ago. It has a tiny little ledge. The ledge is one thousandth of an inch smaller than the lip left by the paint, which is four thousandths of an inch. So what happens is when this sits exactly where it needs to, it perfectly sits over the paint and there is just enough room left for the glue. So here I have a couple little wooden dowels that are exactly the right size to fit in here.
And this will keep everything aligned during clamping. I'm going to heat up the parts, apply some hide glue, clamp it in place. So now that this has been done these guitars will sit like this overnight preferably for 24 hours before I move onto the next step – when we'll install the tuners and put the strings on. We're going to fit the nut and saddle to this guitar. This here is a saddle blank. It's just a rectangular piece of cow bone. I've taken that blank and brought it to the correct thickness and shaped the ends so that it fits precisely in this slot. As you can hear, it's a very tight fit. So, the first thing I'm going to do is I'm going to establish a radius at the top of this that's going to match the radius of the fret board. I'm just going to check the bottom of the saddle for flatness and square, because it's really important that I make good contact. There's a good fit. That's a good starting point.
This is an old guitar-maker's trick: you take a half pencil and that's going to tell me where I need to be height-wise. This one I'm going to actually file off square a little bit, because it goes to the two outside tuners and they actually splay a little bit more. Here's a set of strings. Because everything I do is custom, the spring spacings change from guitar to guitar. So unfortunately, there's no quick way to do this. So what I'm about to do now is set some basic intonation points, and make any fine adjustments in a couple of weeks after the guitar's had some time to settle. Just like the nut has an angle to it so that the strings don't buzz, I need the same angle on the back so the strings don't buzz; unless of course, I was making a sitar.
Okay so, at this stage, everything is very over-sized. Nothing is very refined. It's just some basic measurements to get me in the ballpark. Two weeks from now, I'm going to dress the frets — leveling of the frets, recrowning them and shaping them if it needs to be. I'll set the intonation at that point in time. But right now, I just want to get this guitar to a state, where it can get used to being a guitar; because right now, it still thinks it's a tree. When I string up a guitar for the first time, I'm always in awe.
It's just a few bits of wood and some glue, and now it's making music! It never gets old, and it never loses its magic. I should be pretty close. Okay so, it's been a couple weeks since you were here last. These guitars have been strung to pitch, and they're ready to be adjusted to their final adjustment and final set-up. Set what we refer to as the action, which is string height between the twelfth fret and the bottom of the string. It's kind of a little bit of a ballet dance between bringing the string height down on the nut end, and then correcting the neck relief, and then finally bringing it down on the saddle. And I can take a measurement using this guage. So, this particular string is going to come down by three thousandths of an inch. I'm chasing a little bit less than the thickness of a piece of paper. Okay, the next step in the process is to check the intonation of the guitar.
I have this strobe tuner that I've had for… twenty-something years? A long time, but because it's super accurate. This one is right on. This one's right on. It's really close. I'll tweak it. These strings have been on and off several times. This guitar is now ready to have the frets dressed. This is a single-cut, metal file with the same radius to it as the top of the fret. Perfect intonation happens when the string touches the top dead center. That's as much as we've removed.
Like, sparks! Like, teeny-tiny little molecules. I'm going to repolish these, so they're like little bits of jewelry sitting on top of the guitar. I learned this technique over twenty years ago from a legendary guitar-maker and a guitar-repairer by the name of Roger Sadowsky. He's the guy who taught me how to do this, so thank you Roger. I'm going to be adding a little bit of a treatment and protector to the fingerboard. Now that the frets have been polished, this will help seal and nourish the ebony without making gummy or sticky. I fabricate these little mahogany plates. They fit over the bolts that hold the neck on. It's just a little aesthetic touch rather than leaving exposed bolts. And we can take out the little label protector that we put on three months ago, and trace this to the curvature of the fingerboard.
Flip over to a finer grit. Right now, I'm just shaping the edges of the nut for two reasons: one is aesthetic, but more important, it gets rid of the sharp edge so the player won't feel it. It's more comfortable. And I'm going relieve the back edge. I'm just putting a little bit of this lubricant. There's graphite in it, and it helps the strings move in the slot. The glue isn't here so much as to hold the nut in — there's a couple hundred pounds of string pull holding it down, so it's not going anywhere — it's just to keep it from sliding around when the player is changing strings.
Just put the truss rod cover on. We're at the end. At this stage, there's no more playing, there's no more touching. I'm giving it its final inspection; and once we put it in the case, the next person to touch this guitar will be its new owner. I'm just going to put the packet that contains the documentation for the guitar: certificate of authenticity, warranty information, there's like a care and feeding packet. There's also the key to adjust the truss rod, and there's a little shield for when you change strings so you don't dent the top.
These cases are made in Croatia. They're carbon-fibre experts. In my opinion, these are the finest cases in the world, and as you can see they're fit to my guitars. I send them drawings of each of my instruments. And… that's it. I hope this has afforded you some insight into my craft, as well as the precision and attention to meticulous detail that goes into the fashioning of each one of my guitars. No guitar will ever leave my workbench unless I feel it is the best work I am capable of. More information about my work, how to order, and pricing is available on my website: greenfieldguitars.com Thank you for watching..