Thursday, February 20, 2014

Acoustic Part Eight -- Finish Line in Sight

The finish line is in sight, and like all other stages in this acoustic ride, preparing for finish has been an interesting experience.

I don't have a spray booth in my workshop, and I don't think I can convince my wife that the smell of lacquer in the morning would be a good thing, so off I go on the path of least resistance . . . have the guitar finished by an outside source.  Well, easier said than done.  The pros (Martin Guitars) don't mess with anything outside the confines of their company creations.  The luthier shops in Columbus and Cleveland have determined that, if they decide to take on outside work, it is costly, with the least expensive being $1,200 to spray a guitar neck and body.

The most experienced luthier in Columbus, and also the most expensive, made a comment that got me to thinking critically.  He said, "We think a person who builds a guitar should take it all the way from start to finish."  I think he is correct!  Thank you, John for motivating this cautious old guy.

So, off I ride on the research journey. After phone calls and product research, my friend Larry suggested that I consider gun stock oil.  "What," I asked him?  "I'm building a guitar, not a weapon."  That's when he explained the advantages of using TruOil.  It's easy to apply.  It's inexpensive.  It's durable (think of a rifle being banged around in the back of Bubba's 4-wheeler).  And, the final result is beautiful.

A call to Birchwood-Casey (they're the folks who manufacture TruOil) and a step-by-step tutorial from a real live person on the other end of the call, I'm expecting to receive the stuff I need (sealer and finish) today. Woohoo, I'm almost at the finish line.

However, this stage too, requires a couple special tools.  Geez, in the nearly 80 hours involved in this project, about half the time has been involved in creating special tools or waiting for glue to dry.  But, it's time well spent, or in my case, money saved for the next creation.

Since I'm hand applying the finish, I need a method by which the guitar surfaces can be accessed without difficulty and so that I don't screw up the finish.  StewMac would gladly sell me a metal gadget that will clamp nicely in my bench vice and which will turn in any direction.  A great device, but the down side is that it will cost nearly three hundred bucks.  I don't think so!

What to do?  Whoa!  For years, I've been stumbling over a bicycle stand my son thought I needed, when he wanted to get rid of it.  It adjusts in height and angle.  The top bracket is designed with a trough and clamp to hold a bike frame top tube.  It's sturdy, so why won't it work for a guitar finish stand? It will, and it does.  And, the best part is it's free.

All I needed to do to make this thing work was to create a part that would attach to the guitar body and fit the stand.  A wood dowel with piece to fit the neck joint on the guitar and a threaded metal shaft to attach to the guitar body did the trick.

It's fully adjustable and it turns easily in the clamp.

The same principle works for the neck.  After finish is applied, I can hang the neck to dry without worrying about anything getting screwed up.  I love it when a plan comes together.

Saturday, February 8, 2014

Allmosta Acoustic Guitar -- Part Seven

Remember in the last post, when I mentioned that Uncle Sam's Postal Service saved me from eco-unfriendly government regulations.

OK, let me explain.  I'm into the building process, where the next step is to cut channels and add binding to the guitar body.  Simple, right?  Not so quick.  I can cut the channels, because of the handy-dandy router table I made a while back, but adding the binding is a little more involved.

Why, you ask?  Well, it seems that our good government regulators don't think it is in good form to send certain types of plastic materials through our domestic mail system.  According to their quirky determination the plastic is unstable and susceptible to catching fire.  However, they don't seem to mind if the same product is shipped direct to my home from China.  Figure that out, if you can!  This is why I think we should allow any third grade class in the US to regulate products and process, and to send our good congressmen/women (every one of them) on a one-way adventure to inhabit Neptune -- God help the Neptunese.

How do I know this?  Because, I wanted to add tortoiseshell binding to replace the white stuff that came with the kit.  I called my friend Liz at Martin Guitar,'cause she's the product wizard there, to order the required quantity.  Sure, she said, "We have it. Are you going to pick it up?"  "No!", I replied, "I need you to ship it." 'Can't do", she said.  That's when I learned about the regulation  our Washington braintrust has developed.

Alright, enough already.  Let's get on with the fun stuff.

I received the tortoiseshell binding from China five days after I ordered it on-line.  While waiting for the binding, StewMac shipped the necessary glue for adhering plastic to wood and tape to hold the binding in place, along with abalone fret marker dots, bridge pins and strap button.

In the photo at left, you can see how the binding is glued in place and held firm with tape, while the glue dries in about two minutes.  The blue tape outlines the bridge position, which will come later.

When gluing binding to the channels it is important to make sure that a small portion of the binding is 'proud' of the surfaces. The excess will be removed with a cabinet scraper in the initial process and sanded smooth with the surface to finish the process.

I was expecting this to be a lot more difficult procedure than it turned out to be, and the result is awesome.
I really like how the color of the tortoiseshell compliments the color and grain of the rosewood sides and back.

Next in the process was to apply a heel 'cap' to the bottom surface of the heel (that portion of the neck extending down vertically on the front of the body.  The kit came with a plastic heel cap, but I don't like how it looks, so I chose to cut a piece of Ziricote to finish off the heel.

And, to finish off the backside of the guitar, where the adjoining sides created a seam, I cut a wedge-shaped piece of mahogany to match the neck.  After carefully cutting away the necessary body material, I glued the wedge in place.  (I need to point out that I did this prior to attaching the binding).

 What's left to do?

Shape the nut and saddle, and drill the tuner holes in the headstock.  The tuner holes are easy, it's just a matter of aligning them perfectly on the headstock in the positions recommended by Martin.  Again, measure twice or three times and drill once.  The nut and saddle are hand shaped from pieces of bone to correspond with the curvature of the fretboard and bridge.  If it's done correctly, the strings will follow the curvature and the string action will be just right.  I may need to do a little adjustment when the strings are attached, but I think it will be minimal.

The tape is there to mark the centerline of the neck, so I can locate the string slots.

The next phase is finish, so stay tuned.

Acoustic Progress -- Part Six

Although I like 'simple', when it comes to project detail, I've found that complications pop up regularly in the world of luthery.

Since the last post about my venture into the acoustic guitar-building arena, I've learned a lot more about the building process; how additional specialty tools aid the process; and how current eco-unfriendly government restrictions cause unplanned delays.  But, Uncle Sam's Postal Service saved the day (I'll explain this later), so I don't want to hear any complaining about how you didn't receive Aunt Willa's birthday card on time.

So, just what have I been up to?

After gluing up the body, the neck was the next order of business.  This is one of the most crucial elements in the building process (how do I know?, because my friends at Martin Guitar are so willing to share advice and information), because, if the angles of the heel and neck are not perfect nothing else will align properly and string action will be lousy.  I follow the 'measure twice (or more) and cut once' theory, always, and it works!  The angle alignments are spot-on Martin recommendations.

With the bare neck attached to the body and flush with the top, a straight-edge rule lying flush with the neck surface will ideally be 1/16" - 3/32" off the body surface at the point where the saddle will be positioned on the body. To achieve this, the heel (where the neck meets the body vertically) must be carefully shaved to fit.  And, this is only the start.  The center line of the neck must also be in alignment with the center line of the body.  So, one side of the heel may need to be shaved more than the other, while maintaining vertical integrity.

In the photo above, you'll notice a cavity running the length of the neck, which is the channel for the truss rod.

In the photo to the left, the truss rod is in place, sitting flush with the top of the neck.

The rod is shrink wrapped in a vinyl film for a reason -- to prevent the epoxy resin used to glue it in place from seeping into the rod's movable parts and rendering it useless for possible neck adjustment, down the road.

Next comes attaching the fingerboard to the neck.  This can be done in a couple ways, but the 'simple' rule applies -- press in the frets and dress them prior to gluing the board in place.  Why?  Because, it would be easy to snap off the portion of the fingerboard where it overlaps the heel, if the board were to be glued on prior to setting the frets.

Pressing the frets into the fingerboard is my method of choice.  Many luthiers recommend using a brass hammer to do this, but I don't subscribe to the notion that banging around on critical pieces is the solution to task.  So, I simply (there it is again, 'simple') cut a piece of oak scrap to the contour of the fret board; drilled a hole in the middle of the die and glued in a steel rod, to create a fret press that would fit my drill press.  Then I ran the bulk fret stock through my 'cheapo' home-made fret wire bender; cut it to length for each fret slot; pressed the wire in place; dressed the protruding ends with a file; finished the process with a fret file and steel wool, and voila, a completed fret board ready to be glued to the neck.

Whoa, gluing the fingerboard to the neck is a little more difficult than slapping one board on another and tossing a rock on it for weight.

The headstock is at an angle.  The back of the neck is rounded off.  The heel extends downward and is curved.

I need a new tool!  As you can see, I created a simple jig to hold the neck in place, while a sturdy board rests on the top of the fretboard for adjustable clamps to apply pressure without damaging the surface of the board. This took me all of thirty minutes to build from scrap stock laying around the shop gathering dust.  Damn, I like it when a plan comes together!

When the glue dries, I'll be ready to move on to the next phase of the acoustic dream.  Stay tuned for more progress.