Gibson C-O Classical Guitar Update

Gibson Guitars produced a half-dozen or so classical guitar models from 1957 to 1971.  By classical guitar, I imply acoustic guitar with nylon strings, a two inch wide neck, round sound hole, and a flat or nearly flat soundboard and back.  Here’s a time capsule, from my childhood:

On a cold winter’s night in 2013, I opened the original hard shell case cradling one of the early musical loves of my life for the first time in probably thirty five years.  It was time for this beautiful guitar to sing again!

To paraphrase Andre Segovia, “There is no guitar but Hauser, and Augustine are his strings!”  A pack of once-fresh strings had slept in the case along with a deteriorated elastic capo, some original sales literature, and a few odds and ends, a message in a bottle from 1978. The strings were still sealed and in good shape, so I tried them out.

After stringing up, something in the headstock was buzzing in the key of G.  Examination of the headstock showed that the screws holding the tuning machines were loose.  The screws enter into a fairly thin chunk of the headstock.  Perhaps the wood had shrunken, or, more likely, an over-zealous teenager had put too much torque on the screws.  (That would be me.)  In any case, let’s fix it!

Examination shows that the screw holes are stripped.

As with the Rogue guitar tuner rework in another blog post, I fashioned some thin wedges from small dowel rod to bush up the holes to make them smaller.

The sharpened dowel will go all the way into the bottom of the hole, and will effectively make the hole smaller.

The sharpened dowel is glued into the hole with hide glue, and then knifed-off flush with the headstock.  The finished repair will be invisible as the tuners completely cover the hole.

I took the opportunity to rub down the metal and lubricate everything.  The machine screws allow a tiny bit of gear lash adjustment so now everything runs smoothly.

When this guitar was new, I noticed that the frets appeared to be wire-brushed, with obvious marks parallel with the fret board. String bending is unusual in classical guitar ethos, but soft strings don’t last well on rough fret wires. Time for a fret level and burnish.  These fret wires hadn’t been touched in decades.

Note the ‘fret zero’ next to the nut. The ebony nut is slotted, but the effective slot depth is set by a thicker fret wire.

Fret wires were leveled, crowned, and burnished with steel wool. I didn’t polish them to a really shiny, slick finish, because I want a little ‘grab’ when I fret the nylon strings to stick them down while playing.  This rosewood fret board hasn’t been this clean since the guitar was new back in 1968!

I have no record of the original Gibson classical guitar string gauges.  Modern strings on the simple, uncompensated Melamine bridge saddle yielded unequal note temperament, made even more painfully obvious by these darned electronic tuners. I purchased a stack of bone saddles and went to work.  This saddle was an intermediate attempt to ‘find’ the proper compensation for this particular guitar.  But it’s not pretty.

Here’s another view.  This material is sustainable Vietnamese water buffalo bone.

Another view of the saddle.  The string slots were an experiment, later dropped from the final version.

This is a little simpler approach, and yielded accurate intonation to within a couple of Hertz. See the break angle?

The slight taper and no string slots allows a bit of string-height adjustment of the action, as this saddle can slide a bit from side to side in the bridge slot.  The dark streak across the bottom of the bridge where it is glued to the cedar sound board has always puzzled me.  Perhaps it is a feature of the wood, or a little too much glue at the Gibson factory.  It’s always been there and after almost fifty years, shows no sign of fading.

The light reflecting from the bone highlights the curves filed into the bone to accomplish the intonation.  There is NO comparison between the tone of the Melamine bridge and the bone bridge.  Yes, this sort of an update makes a noticeable difference in the volume and tone of this guitar.

In this view, the final figure of the bone is more apparent.  The top of the bone is split into two diagonal sections.

Jen does a final test of string harmonics versus fretted note.  Those little electronic tuners didn’t exist when this guitar was built, but this Gibson has updated nicely to comprehend modern strings and music technology.

Old guitars, like old horses and old dogs, deserve care and respect.  In return, old guitars will offer up your music in a voice that transcends time and space, and a perspective of history that cannot be replicated with an effect pedal or VST plug-in.  Take care of those old guitars…  they don’t make ’em anymore!

Thanks for reading all the way to the bottom!

CONTACT INFORMATION – David Latchaw  281-636-8626