Body binding and purfling

First, I've been slow posting this past week because Tuesday (1/16/07) was the first day of class this semester. Moreover, my office was moved during winter break, and so I've been wrestling with boxes and networking in addition to the usual demands of new students.

As per previous post, binding and purfling ledges were routed. I went ahead and took care of the non-cutaway side, as it's a tad easier to bind.

Part of my reason for blogging my building is to be honest about this process. Neither am I god's gift to lutherie, nor am I without skill. I changed the name of this blog because the old title made me sound too incapable, too pathetic. I am neither. But, I have to work at this, and some times it is a struggle. The only way to improve skills is to try and fail and try some more. Now, I don't think I've failed -- far from it! But I've had to follow the "two steps forward, one step back" method as well.

Do I have the courage to say all this in a public forum? Is it not wiser (from a marketing viewpoint) to allow those folks for whom I build guitars to nurture an image of a master artisan whose every move leads to a predictable and calculated outcome? Perhaps it is. But that doesn't feel right to me. I do know what I'm doing. Still there are surprises along the way. Not all surprises are welcome. Some turn out in a way not intended. So, I have to go back and fix things. I am and will always be learning. I cannot believe this is not also true of every instrument builder, even Charles Fox, Kevin Ryan and Jeffrey Elliot. I bet Torres had to fix a few of his own mistakes now and then.

To my mind there is no shame in producing by hand an instrument which does not display the cosmetic perfection of a factory instrument. If you can tell it's hand made, that's no tragedy. It's an instrument -- a vehicle -- for the making of music. If it has an interesting voice that speaks to the musician and that musician's listeners, if it's playable and allows the musician to try new ways of playing, or to write new songs, or if it inspires a new musician to learn to play and brings the satisfaction of participating in acts of music-making, then it is a complete success. Cosmetics be damned.

That being said, I try hard to make 'em as pretty as I can. Each guitar is better than the last, and I work steadily to make that trend continue.

I'm using thin b/w purfling on the top, back and sides, as well as fine herringbone on the top. The idea is easy, but with bindings, two fine purfling strips and herringbone on top, coupled with the fact that you install the back bits and top bits per side simultaneously, it's not hard to end up with a gluey mess. It's also possible for the fine purflings to become misaligned. When they do, you have to yank it all apart, douse it with water, realign and re-clamp. Ugh!

Clamping, as you can see, is done with this mediaeval device, rope and wedges. Oh, yeah, it also helps to do it all before the power failure hits (as it did this morning, hence the mag-light illumination). Fortunately, I had everything in place and most of the ropes on. You can see that I'm clamping the binding/purfling around the lower bout, and that the upper bout remains on the "to-do" list.

Already the voice is changing quite a bit. I indicated in a previous post that the sound of the box is changed completely by the binding. At the halfway point already there was more sustain and a clearer, deeper tonal response from a fleshy-thummed thump.

Body

I installed the carbon fiber stiffeners for the tops of the neck and end blocks, let it set and glued on the top without thinking that I should take a picture. Sorry, I'm still getting used to this whole "documentaton" trip. Here's the body fresh out of the mold. Note the overhang around the top.

Some tools are just a miracle of ingenuity. To me, router bits with bearings fall into this category. I use a flush-trim bit to kill the overhang. It has a little bearing (and by that I mean not a single ball bearing, but inner and outer steel rings loaded with ball bearings in between, so that the two rings roll freely of one another) whose external diameter matches the diameter of cut of the blades. The bearing reads the bent sides as the rotating blade cuts the overhang to perfectly (or close enough) match the shape of the sides.

And, here's the result. I've also routed a channel and installed a bit of cocobolo (cut from a discarded fingerboard extension) at the top of the cutaway. This gives a very defined edge there and will provide a nice transition from body to neck heel.

At this point, what's been just a gob of sticks and glue not only begins to look like a musical instrument, but commences also to give utterance. It's certainly not singing, or even talking, but gives a sort of shrill cough. I used to think of binding as trim and nothing more, mere decoration to define the edges of the guitar. When I began this quest I read someplace that the purpose of binding was to protect the guitar, that stiffer rosewoods around the rim can protect softer cedars and spruces from breakage as the guitar receives the inevitible bumps it will receive. If the binding breaks, the guitar can be re-routed and new binding installed, then re-finished. Certainly the binding performs these two functions, but its primary purpose is much more central, and one I couldn't have guessed prior to building. It does bind the top and back to the ribs. The aforementioned router with bearing-tipped bit is used to cut a rabbet (shelf to receive the binding) around the edges for binding installation. That channel cuts through the top plate into the sides. The binding binds both to sides and top (or back), actually surrounding the top (or back) plate. I know that this has a structural effect on the instrument because the voice changes from a cough to a speaking voice once the binding is in place. The box will talk.

As the wood relaxes, it starts to sing.

Redwood and Sycamore

I live right close to Nashville, a lovely city, which seems to host more guitar players per square inch than any other city on earth. At the invitation of one such, which I'll refer to here as PGM, I took three of my instruments on the road yesterday to that fair city for a showing. PGM has sought in the last six months to supplement his keen piano playing skills with a facility for the guitar. Despite a full-time job in a position of great responsibility, he's managed to put in between one and two hours of practice every day sinc commencing his lessons. It shows in his playing!

Anyway, I owe a debt of gratitude to PGM for his immense hospitality yesterday. I had three of my guitars (including the two pictured in the 12/26/06 and 12/28/06 posts, as well as the little maple guitar with the adjustable neck) in a conference room with PGM and several other fine players. It is always useful to me to hear my instruments played; they just sound different from the front than they do behind, and it's easier to gauge projection and balance from a distance. Players' comments are always welcome to me, both positive and negative. It's nice of course when the positives outweigh the negatives, as they did yesterday. I need all the encouragement I can get!

PGM liked the red guitar. He's interested now in having me build essentially the same guitar, but with sycamore back and sides and a redwood top. So I've put the back and side set aside, and will soon be ordering the top and other supplies. HUZZAH!

Apologies to those quoted herein

If ever you read anything well-written herein, likely the source was someone other than myself. My intention is not to take credit for things penned by others, and I'll try to remember to include citations. The last post, for instance, contains a few lines from T. S. Eliot's "Four Quartets." Eliot's poetry is with me always, peppers my thoughts, and so the likelihood of my failure to provide citation is high.

Also, to protect the identities of living persons depicted herein, I invent aliases.

I shall do my damnedest not to offend either by sins of omission or the latter sins of comission.

Progress and reflection ...

This blog is rapidly becoming a "how to" document, which is not what I intend, nor is a "how I do it". But, I suppose, that's part of it, so I'll go with that and try to sneak more of what I really want in here as well.

Here's the sapele guitar in the dished sandpaper workboard with the ribs being shaped to receive the top. Once they're shaped, I install the linings. I use kerfed linings rather than solid linings. I've tried the solid kind, but have switched back to the kerfed style. You must bend solid linings, which is truly no hardship, but the solid linings are stiff and therefore difficult to fit perfectly inside the bent side. Moreover, they are not as wide as the kerfed variety, and so supply less of a gluing surface for the top and back than the other.

The drawback for the kerfed variety is that they break easily. Soaking the mahogany kerfed linings in water helps quite a bit; I've used boxwood as well, but it seems to stay more brittle when wet. Here you can see linings installed on the back of the sycamore guitar, and the bass side lining for the top clamped in place.

My original intention with this cutaway design was less to provide access to the upper frets than to introduce a bit of asymmetry in the appearance of the guitar. I'm really happy with the way it's playing out with this instrument.

It is probably stupid of me to announce how pleased I am with the sycamore box in a public forum. All manner of disaster could strike. Until it's done done done -- strings on, singing away -- the box will live in a crowded and cluttered shop filled with heavy equipment and sharp tools. Accidents, as Prof. Costello so brilliantly enunciated, do happen.

And, far be it from me to fail to credit myself where credit is most certainly due. I am easily the most dangerous force in the universe in regards to this embryonic instrument. As it speaks to me from the future I envision for it, I hear a voice with authority, not deep, but not without a low end; clear and penetrating like a trumpet; sparkly as a simmering brushed cymbal. But I will assault the wood with sharp tools, many powered with electricity, seeking to cut away that which is not guitar. I am capable of weakening that voice, preventing its clarity, even threatening its ultimate existence. Control over my tools, even my own hands, is educated and practised -- but far from perfect.

Every instrument is an invitation to learning and disaster.

"And any action
Is a step to the block, to the fire, down the sea's throat
Or to an illegible stone: and that is where we start."

And so I have learned the hard way that much of lutherie is not design and execution, but making the best of mistakes that are as certain as the sun is to rise tomorrow. Vision of the final instrument often must be altered to correct errors. I do not say "hide mistakes," because there is no intent to put flawed instruments in the hands of players. There is an ongoing recalculation of optimal strategy at every point in the building process.

That is, there's a composition, but there's improvisation as well. I'm just reacting to that fickle organic stuff -- wood -- which seems to have a mind of its own.

And, of course, my own abilities and limitations.

Sycamore thumbscrews

Maybe I shouldn't call him PH; that's just what he called himself after we played with photobooth on my macbook and produced the photo atop the last post. Actually, it's EclecticGuy of OccasionalBlog. He and I met 35 years ago when I was whistling "Thick as a Brick" in junior high school gym class, and he recognized the tune. We've been talking music ever since. He's a great friend and an outstanding musician who's taught me many, many things. So I'm charged beyond words to be making him an instrument.

Anyway, this goodie is a side bender. When you get the back and side set from your supplier, the pieces need to be thicknessed and trimmed. I've learned that prior to using the bender you must mark the sides. Then you give 'em a healthy dunk in some clean water and make a sandwich. After you've eaten, you make a sandwich consisting of, from the bottom up, steel slat, side to be bent, bending blanket (an electric goodie which heats up to 450 degrees -- though you don't want to get it that hot), and steel slat. Slide it into the bender and tighten the waist press. Turn on the blanket and wedge a cooking thermometer between the upper slat and the blanket (I usually put it between the waist and the hip). Monitor that temperature, baby! When it says 225, start screwing down the waist press. Take it all the way down! (But, of course, stop when you hear your wood break. If it does, break down and cry. Then back out and try to fix it with glue and voodoo. If the wood gods are with ye, breakage will not occur. The sycamore sides I bent the other day might as well have been made of rubber -- over 1/8" thick, but bent easily, and held their shape nicely. But I digress.) There are two spring loaded thingies you can slide from the waist up and down over the bouts. Do this slowly to avoid breakage.

If by now you've not turned off the blanket, it's 350 degrees, and your sides are rapidly attaining charcoalhood. So, throughout this process watch that temperature! Different woods take heat differently. This Sycamore bends at low heat but tends not to char. Mahogany seems to like more heat for bendability, but will char. I've had no trouble bending flame maple, but it seems to be happier with more water and higher heat. Cocobolo bends nicely, but is so oily you have to scrape off cooked sap. Yuck!

Here you see clamped into the two halves of the external body mold the results of bending. I am delighted with how well they turned out.

Here's a lovely partially braced mahogany top (for the sycamore guitar). It sits on a towel covering a dished workboard. The workboard is covered with sandpaper -- hence, the towel. The surface of the workboard matches the surface of a sphere of radius 12 feet. That's a fairly standard workboard for the back, but tight for the top. Some guitars I build have tailpieces, so I like a tight radius.

How does this bracing get done?

Here are two lower face brace blanks. You can't really see it in the photo, but the planes of the grain lines run parallel to the largest surface in these rectangluar timbers. That's what you want for stiffness. So, I pull the top and towel out of the way, and grind one edge of each blank against the sandpapered surface of the workboard, thereby transferring the 12 foot radius onto the glued edge of each brace. Slick! Then I use other sophisticated devices (i.e., a nice flat hunk of MDF with sanpaper glued on to it) to give the rest of the brace its shape.

This dandy is called a go deck. I don't know why. But it's really a cool and low-tech way to get braces glued in place. I spread as thin a layer of glue as I can manage on the curved edge of the braces with a stiff bristled little paint brush, put the brace in position, surmount the brace with a wood scrap clamping caul, and hold it in position with these fiberglass go sticks. Each one exerts a surprising amount of pressure, and collectively you can create firm and even pressure to get your top and back braced.

Finally, I installed neck and end blocks in the sycamore guitar. Here the wood is being tortured with glue and clamping pressure, forced to do my bidding. BWAAAHAAHAAA!

New year, new instrument (for Pineapple-Head)

As you can see, this guy needs a guitar. We'll call him PH for brevity.

As per previous post, PH is a classical player at the core. But he hears things he'd like to play more readily accomplished with steel strings. How to set him up?

I'd previously braced a top and a back for another instrument with the same body as the red guitar. When PH played red, he got confused about where he was on the neck. Now, PH is one hell of a player, and the confusion was my fault. It has white side dots on maple binding, so it's hard to tell where you are. The 14-fret body join was confusing since he's used to classicals with the traditional 12-fret join. So, I WILL PUT VISIBLE SIDE DOTS ON THE PH BOX FINGERBOARD! I'm also thinking short scale, mostly to help replicate that loose nylon string feel. I'll do a slotted peghead because of PH's affinity for classicals, and because they're cool.

I checked the dimensions of this braced top, and I can do a 24.9" scale with a 13-fret join. That ought to offer some key features for PH. Reduced string tension should offer a wider variety of string choices; silk and steel, for instance, might let him keep the tension-feel of classical strings. Also, it puts the bridge near the "sweet spot" of the top, with that lovely tonal response. Besides, I was quite happy with the bracing I did on the top. It's got a simple ring of black walnut as a rosette, and black walnut sound-hole binding. Simple and elegant.

LMI thicknessed the back as a classical for me, and it's somewhat thin for a steel string. So, I put 4 rather than 3 ladder braces on the back, and I made 'em tall. I want it stiff for sustain, and I want to emphasize the midrange.

Next: to bend the sides.