Quick Output Jack Tune-up On Martin X Custom

Near the top of the heap of all acoustic guitars available today (yes, I know, I’m a Gibson Guy) is the Martin X Custom.

This beautiful specimen had a loose output jack and was suffering from a low battery.  Let’s take a look!

The gang at Jealous Creatures use this guitar for songwriting and performing.  Check their Website at www.jealouscreatures.com  !

The output jack masquerades as a strap pin.  The loose nut is underneath this trim bushing.  Here we go!

The strings need to come off so that we can get inside the guitar.  While we’re there, we will replace the battery.

With the trim ring out of the way, we can see the actual nut that needs to be tightened.  However, there is another nut inside the guitar.  I want to pull the jack and readjust the number of exposed threads so that everything is secure.

If the inside of the guitar is to the left, this is the washer stack-up.  The inside nut is still threaded on the jack.

Here is a fresh commercial/industrial battery, placed inside a Velcro bag.  This sticks inside the body of the guitar where another piece of Velcro is fastened.  Note that we need to do a little ‘lead dress’ to get all the wires out of sight!

The piezo pickup lives under the saddle, inside the copper braid that you ‘might’ see down in the bottom of the slot.

Re-assembled, squared away, restrung, and tuned to pitch. This is a beautiful guitar and sounds great!

Speaking of sounding great, check Jealous Creatures at their Web site and on Facebook !


Contact: David Latchaw  EE


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

Rogue RD80 – STOLEN – Setup and Product Review



The Rogue product line is the ‘house brand’ of a large nation-wide guitar outlet chain.  These guitars are designed in S. Korea and built in China, intended to be a low-price entry-level guitar.


This particular guitar, a dreadnaught RD80, was a scratch-n-dent guitar, previously owned for a short time by a local school’s music program. It was returned under warranty because one of the tuning machines had shelled out.  To the credit of the local store manager, he honored the warranty AND marked the guitar down further for me.  I happily purchased it, intending to refurbish it for one of my students.


There were a couple of challenges in refurbishing this guitar, as we will see below.  I was not sure that the guitar would be worth the effort, but on the other hand, my student loved the guitar and wanted badly to play it.

OEMtuners The OEM tuners are junk. However, I thought I could take them apart, shuffle in some parts from other tuners, and make them work.  Perhaps a little trombone slide grease and judicious filing and fitting would be in order.


PlasticBridgeHere you can see that the plastic OEM saddle had already begun to experience some serious cheese-slicing from the tension of the strings.  This saddle will be discarded and a synthetic bone compensated bridge will be put on order.  It is a standard size and so will require a minimum of gun-smithing to make the new saddle fit.  While removing the string pegs, I reached inside the guitar to push them out from the inside.  Apparently the holes for the pegs are bored after the bridge is installed, because I could feel chips where the soundboard had broken out during the drilling process.  This is not unexpected from a mass-produced item, but it may be an issue in the future.  Stay Tuned!

TunerSurgery1An examination of the OEM tuners showed that they had ‘some’ adjustment, and could be made functional.


Here you can see the stripped brass gear.  At least brass is recyclable.



After doing some gun-smithing, I re-installed them.  You can see that I left off the covers.  This would allow me to ride herd on the lubrication and keep things in alignment.


What to do about the paint pen?  A little Ax Wax on a rag and some elbow-grease lifted the paint and left the original poly finish in fine shape.  You can see no trace of the paint pen at all.  Thanks for the tip, Pete!


Here we have restrung to tension and checked the neck.  Surprisingly, this inexpensive guitar has a truss rod.

Checkout1Jen checks out the guitar.  After a little playing, the guitar comes out of tune.  Despite the tuners, the rest of the guitar may be nice enough to justify a little more time and effort..


A set of Gotoh tuners were secured via eBay.  These tuners are gold plated, which I thought would look less tacky than the chrome OEM tuners on the black finish of this guitar.  In this pic, I’m reaming out the headstock for the larger 10mm tuners.

DowelSandThe mounting screws on the Gotoh tuners are in a different position than the OEM tuners, so the original screw holes would be filled with this dowel rod, sanded down to about 3/32 inch.  A dab of black nail polish (it’s polyurethane too, remember?) would secure the dowel and finish over the repair, part of which would be underneath the tuners anyway.

DowelClipHere I’ve driven the dowel into the hole and am clipping it off near flush with the headstock of the guitar.

FlushCutThe dowels were trimmed flush with the back of the headstock.  Then, black fingernail polish was used to touch up the repair.  A couple of coats were adequate to seal the wood and leave a nice glossy dot where the repair had been made.

NewTuners1Here are the gold Gotoh tuners installed in the guitar.  The hole filling repair is almost invisible.  And they look nice!  A vendor on eBay has some stock branded “Tacoma” Guitars.  Tacoma was a US-based builder for a while, then were purchased by Fender and apparently phased out.  Look for their hardware on eBay if you want some nice stuff at clearance prices!

NewTuners2Another view of the tuners, with a set of Ernie Ball 80/20 strings that Pete recommended.  Wow, this guitar really sings with the different strings.  Nothing against the Martin set that was on it before, but the Ernie Ball strings really made this guitar come alive!

Checkout2Jen checks out the guitar.  Note smile on face.  But wait, there’s more!

Checkout3OK, here’s the product review.

The Bad :

The soundboard is plywood spruce, and the fretboard is not first-quality wood as there is a funny grain irregularity.  The fretboard workmanship was a little rough and some of the fret wire ends could snag a cleaning rag (or your finger.)  The carnage underneath the bridge, the result of boring the string peg holes after the guitar was assembled, was almost unbearable. A small handful of wood chips were removed from the interior of the guitar.  The cheap tuning machines and cheap saddle was on par for a low-priced instrument.

The Good:

The fret wires were easily refinished and polished and the ends filed smooth.  The funny grain irregularity in the fret board almost disappears if the fretboard is kept oiled.  Replacing the tuners was a no-brainer.  The new strings and saddle made a huge improvement in the sound of this guitar.  After modifications, this guitar has a great voice.

Bottom Line:

My original student changed jobs and couldn’t keep the guitar, so I now use it daily.  I enjoy playing this guitar as much as ANY guitar I’ve owned.  The Martin resonance of the body and the almost-Fender chimey sound prevent me from putting this guitar back on the stand.  I play it until my hands ache.  It is an incredibly fun guitar to play.  I wouldn’t hesitate to perform live with this guitar.  Maybe it’s because I’ve whipped this scratch-n-dent guitar into shape, but I think maybe it’s more;  The exceptional sound just draws me back to this box.  Take off your gear-snob hat and do not cast aside these Chinese guitars.  While you may look at a Chinese for a beach guitar, you may find a diamond in the rough.


UPDATE 23 February 2014 – This guitar, bag, strap and strap locks, electronic tuner, and a couple of sets of strings were lifted out of my office at work.  I never expect to see this guitar again, but stranger things have happened!  So, after all, it’s a good enough guitar for someone to walk past more expensive guitars and take this one.  Rock and Roll!