Archive for the 'Continuing Education' Category

Girdis Guitar Finishing Project

March 10, 2012

Through a Google search, I was contacted by a gent from Guemes Island who was in possession of an unfinished Rob Girdis parlor guitar.  After discussing my background and having studied with Rob, we agreed that I would take on the job of finishing the guitar.  It’s a koa parlor with snakewood binding.


I’m looking forward to this project, as I can still learn from Rob by examining and analyzing the construction of this guitar while I proceed with the finish.  It needs the shaping and installing of a snakewood bridge, bone nut and saddle, tuning machines, and end pin.  The guitar needs to be prepped for finish, then the application of a lacquer finish.  Finally, strings and setup.


I’ll carefully document the dimensions and materials, and take a few iPhone photos of inside the box.  It’s koa all around with an interesting trilaminate neck of mahogany and ??



The headstock treatment uses a backing laminate of the same wood in the neck, which may be boxwood.



One thing Rob was proud of was his binding and purfling work which really shows on this guitar.  I remember showing him progress on one of my earlier guitars where he commented, “Nice work, but, you still have a way to go on improving your binding.”  I do possess now, the example to work toward.





I have access to an extensive photo library of Rob’s guitars.  I should be able to replicate tuners and bridge design to ensure the finishing of this guitar matches his design.


November 23, 2010

This is a test.  Had this been a real emergency, it would not have been a test.

What’s Next?

July 1, 2010

The year is half gone and two completed guitars have gone out the door.  One guitar is in process, and there’s grand plans to start building ukes.  I’ve also got my sights set on building a guitar modelled after a Gibson L-00.  The Uke and Gibson project requires the building of molds, templates and jigs.

I’ve got a handful of repairs in the backlog which I’ll have to balance with the new construction.  I’m wrapping up the neck reset for the Gretsch New Yorker, and I have several major overhauls which have been waiting for an opening.

I’ve finished rebuilding the router table, and have designed a jig for brace radiusing.  I’m looking into CNC tools and software as a side opportunity.  CNC could be a valuable skill/tool especially if I begin to productionalize the building process through repeatable construction processes.

All this and I’m starting a program called Alt Routes to Secondary Mathematics Certification.  Translation:  High School math teacher.  The program begins July 12.  Summer courses end early August, then I dive into a school year long internship at a local high school.  By the end of the school year, next June, I should be certified.

“From ding ding to wobble wobble”

December 5, 2009

Today I had the honor of working with Rick Davis on soundboard tuning.  Suffice it to say that it is a non documented process with very little scientific evidence that allows one to say what you do or how you do it.  The title of this post is as close as one can get to putting it into words.  Fundamentally, a guitar top plate joined and thickness sanded down to 0.125″ will have a sound, kind of like a ding ding.  A note, or set of notes which ring out and sustain.  The counterintuitive piece is you want to eliminate that ding ding and get more of a wobble wobble, a lack of distinct notes.  If those distinct notes are left in the soundboard, they will be excited by complementary string notes, and not by others, meaning that notes across the spectrum will be treated unequally resulting in wolf tones, dead tones, and select rich tones.

After the top is braced and preliminary shaping is done, the soundboard still has some ding ding to it, and the removal of bracewood is done until the ding ding turns into wobble wobble.  There is a very thin window which goes from wobble wobble to an exploding soundboard:  one which will not sustain the tension of a fully strung guitar.

We spent considerable time discussing the function of each brace, and whether their function is structural, tonal, or both.  Essentially the braces from the soundhole side of the X-brace toward the neck joint are structural.  The X-brace itself from the X toward the butt is both structural and tonal, and the remaining finger braces in the lower bout are purely tonal.  Now before I go on, Rick mentioned that everything he says is wrong, but that it works for him.  There are a thousand ways to look at soundboard tuning and the understanding of brace shaping and function, but they are all wrong.  Which boiled down means; if there was a right way to do it, we would all be doing it.  Since there is no right way, there must be all wrong ways.

So, you start with a ding ding braced soundboard, using bracing patterns that are generally accepted, then you start shaping and listening until you just hit wobble wobble.  First, preshape the braces into a taper (except where the X-braces join), glue them to the soundboard preferrably using vacuum clamping or go-bar clamping.  Next taper the ends, down to nothing for the tone bars, and down to 1/8″ thick for the structural braces.  Then scallop all the braces below the X with diminishing peak height toward the sides.  All during this process, listen to the tap tone and hear the changes and work toward the wobble wobble.

Guitar 802 – Prepping for buffing

August 2, 2008

Finished the jig/vise which I will use to hold a guitar body upright. I built this in anticipation of having to sand the rim to smooth down flat before buffing.


I added a radius to the boards to compensate for the arch in the top and back.


The braces under the bench were 3/4″ too close to the bench top, so had to add a filler piece between the bench and the vise boards.


Finished it up by gluing carpet pieces to the inside for protection of guitar surface when clamping into vise.

It’s a nice day out today, so rather than use my newly crafted vise, I sat outside and held the guitar in my lap while I ran 600 grit sandpaper over the guitar, getting down to the brush stroke channels, and removing drips and dribble streaks. Next, 800 grit, then 1000/1200 wet sanding before I try out the buffer. I’ll definitely use the new vise for the buffing operation.


Back Home

June 27, 2008

Whew.  Back from my contemporary guitar making class.  5 solid days of intense information sharing.  I’ve posted my notes and photos on the ASL page of this blog, which is password protected.

Preparing for ASL

June 21, 2008

Tomorrow I head off to Portland for a 5 day course called Contemporary Guitar Making.  The course is offered by the American School of Lutherie, aka, Charles Fox.  The description:  CONTEMPORARY GUITAR MAKING is a window on guitar making’s dynamic new reality. Today’s high quality guitar making is based on an accurate grasp of the acoustical behavior of the instrument and a working knowledge of the most effective means of the craft. Armed with these two things, a growing number of world class luthiers are able to systematically optimize important qualities of their guitars, and to build enough of them to both advance steadily in their craft and make a comfortable living. CONTEMPORARY GUITAR MAKING invites you to share the understanding and the techniques that make this possible.

Hmmm, world class….comfortable living….

I’m looking forward to the exposure of information and techniques, being essentially self taught to this point.  Tomorrow I pack up, and I’ll leave just after lunch to get to Portland in time to hang with my step-sister, Shannon, and her family.

Gotta pack my laptop (so I can post daily progress reports), my new Kindle (birthday present from Carol), camera (to document through photos), cell phone (to keep contact with outside world).  Funny, I’m off to learn about the world of wood and craft, yet I’m taking nothing but technology.