Wednesday, March 5, 2014

Sucky Weather Does Not Stop Guitar Building!

Here's this first. Guess what it is:

That's where the hole in the middle of the front of a guitar comes from, which a lot of people call "the sound hole," but actually, it's the air hole that lets the top, back and sides vibrate in the lovely way that creates the guitar sound. More on that much later.
Bruce Roper, the luthier at Old Town School who is making a guitar for me, cut this sound hole from my sapele guitar top Wednesday morning in a series of meticulous steps that also included building a rosette that encircles the hole. I'll show you that in a bit.

What a ghastly day! The car went to the Botanic gardens with my wife and her good friend, and I packed my camera and stuff into a backpack and headed for the CTA so I could get to Bruce's workshop and move things along on the Buildmyguitar project. It was not an auspicious morning. My fancy tripod fell out of my backpack and the top snapped off as it hit the ground. Amazon is sending me a better new one. I am sending them money.

Bruce lives and works in a neat little space down near Lincoln and School, where he has his apartment, his recording studio and his guitar repair and building shop. To get there, I have to go to from South Boulevard in Evanston to Belmont and then cross over and get the Brown line and go backward a little bit until I get to Paulina, which is the stop for Bruce's place.

I don't mind the trip at all. It's snowy and everything that was dingy, frozen and gray just a day ago now has a mantle of fresh snow to perk it up for a while. It's great to look at Chicago from the El. I used to take it to work every day when I first joined the Tribune in 1979. I thought of it as a very romantic ride past the lives that countless thousands of Chicagoans had built over time.
 I would write poems in my head on my way to work. It is an easy city to fall in love with, despite its challenges.

Bruce was shoveling snow when I got to his shop (after a stop at Wishbone for a coffee and a biscuit and some bacon). Cheery about it all, he unlocked his shop and led me in. What a vision.

What you can see here are the fiberglass splints Bruce uses to hold the glued bracing down against the back of my guitar. What you don't see is that the guitar back is sitting on a piece of wood that has just the slightest curve in it so that when the whole thing dries, the back will have just the hint of an arch in it. All my guitars have that and I have seen how it is done at Martin's Nazareth factory and at L'arrivee Guitars in Vancouver. But this is how it's done in a small shop that has no fancy vacuum presses or lines of guitar builders. It's just Bruce and the wood. But he has his ways.

The braces need to be held down with even pressure all around so the top shapes right and they do their job once the instrument is assembled, adding lots of strength to what is basically a fancy, thin hardwood box in this case. Bruce used a belt sander to shape the braces before he glued them down. There is a reenforcing strip that runs down the middle, holding both sides of the back and the strips of walnut and sapele that run down the center of the back in solid place. Those orange sticks are fiberglass Bruce bought at a home repair center. They are wedged up against a piece of plywood that hangs above the workbench. It's a smart way to do the job.

But I would learn Wednesday morning that there are a lot of smart ways to do the job when you work alone. Bruce will teach you how to make a guitar in his guitar building class, but mostly he is working alone. He has just two hands and lots of tools to help when he needs them. You learn the value of practice when you watch him at work.

The challenge today will be to cut the trench for the rosette around the sound ("air"?) hole in the center of my guitar, then to cut the actual hole. This is delicate work with a high potential for creating disaster unless you know what you are doing. Bruce knows what he is doing. First, he marks the top so it has the same measurements as the 1939 Gibson Nick Lucas that was the model for this guitar.

Bruce is using a compass to draw the circle he will follow to dig the channel for the rosette he is building for the guitar. The pattern is tortoise shell, green wood and then another strip of tortoise, very simple and quite lovely. First that gets cut.

He is using a Dremel Tool with a hole cutting jig and a special bit that does the trick (but can cause some problems in wood that is so hard.) Looking closely, you can see the inside line he will use to make the actual hole. The rosette trench has to be cut first, then using the same axis (a pin that sticks up through the top of the guitar right in the center of what will be the sound hole) he will cut the hole. Everything about this part of the guitar depends on that center pin. If that is setup correctly, the geometry of the hole and its rosette will be perfect. It takes a couple of passes to make sure the trench is cut to the proper depth. It's careful work. You can't make it too wide or there will be an unsightly gap around the rosette on the outside. Too narrow and the strips used to make the rosette won't fit.
He doesn't actually pronounce the work done. He just takes the three strips and sets them in the little trench, starting at the northern most end. They fall perfectly into place. When he has pushed them all into place, he trims the ends and there you have it. The first part of the process is done!

See how they fit down in there? The next step will blow the brain right out of your head, as it did mine. Bruce gets those strips down in the channel, pushes them down to make certain they are in place and the grabs....guess what? A. glue made from horse hides. B. glue imported from distant Asia made from the carapaces of beetles C. Elmers. D. Can't say?

Superglue. That's right, Superglue.

Here is what it is doing. If you have ever seen a plumber sweat a copper pipe and then let the solder draw itself into the gap, you will get this right away. The Superglue, being super, does exactly the same thing. It seeks out every gap, every spot it can find, and sinks in. Because Bruce wants this part to go quickly, he is not happy with the ten seconds you have to wait for Superglue to dry. He has a drying agent he sprays on it. It sets and there you have it, a near perfect rosette ready for sanding.
He has to sand it because its not exactly level with the guitar top in some places. It will be soon.

He's taking a belt sander with fine grit paper to the rosette. It cuts it all right down to the surface. "You always have to keep it moving so it never has a chance to scratch into the surface of the guitar," he says. It takes just a few minutes and what comes out of it is wonderful.

Next, back to the center pin for five passes with the Dremel cutter again. Each time, Bruce takes just a tiny layer of wood away until the center finally rotates on its own. This day's work is just about done.
Here is how it looks:

Next step: top bracing, then bending the sides and moving toward some serious gluing!
Stay tuned.

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