Epiphone Dot Gets a Customized Bigsby Tremolo

Matt with My Twilight Pilot lusted for a black Epiphone Dot with a Bigsby tremolo assembly. Could the Unbrokenstring Crew rise to the occasion and make it happen?
It don’t get mo’ prettier than this!


The Bigsby needs a small modification, so that the tremolo bar can swing over the strings.  Here, the Bigsby is disassembled so that the modification work can begin.


This piece limits the swing of the arm.  So, we will carve on this to change the limits.  We don’t like limits.


After the carving, the metal is sanded to a uniform satin.


Successively finer grits remove the scratches from the previous operation.


This metal polish is made in Germany.  The Unbrokenstring Crew uses this stuff to polish fret wires.  Likewise, it will polish this Bigsby so that it gleams.


We’re just about there with the modification.  It can stand a little more carving.


The tailpiece is centered on the centerline of the strings, not necessarily the center seam of the lower bout.


When the body of the Bigsby is correctly positioned, there are two places where the metal touches the finish of the guitar.  While we are adjusting everything, some painters tape protects the finish.


We are committed at this point.


Two strings are installed to tension the Bigsby into position.  The location of the two additional screw holes are determined so that the whole assembly is straight with the neck before the holes are drilled.


This drill bit is in a spring loaded shell, which forces the actual bit to be in the exact center of the hole.


The strings are ON and now we can proceed with the setup of the Bigsby. See the small nylon washer where the spring fits?  This is an essential part of the setup.


String tension lowers the height of the tremolo bar.  We need to be in tune before doing much more of the setup.


The StroboTuner is spinning away while we tune and set the intonation of the instrument.


What is this?  We have a couple of screws that are having an acetone bath.  Why do you ask?

While we’re working on the guitar, these strap locks are going onto the guitar.


This is the half of the strap lock that goes on the strap.  Both sides are shown.


Those screws that were washed in acetone were painted with black lacquer, and cover up the inserts in the body where the original stop bar was held.  Pretty, isn’t she?

Thanks for reading all the way to the end!

CONTACT – David Latchaw EE


Gibson Les Paul De-ghetto-izing and Rewiring

Quyen found this 2013 Les Paul Custom Lite on Craigslist, and purchased it from a church musician.  The instrument was everything he wanted, except the controls were not the traditional Les Paul controls that he was familiar with.  Could the Unbrokenstring Crew make the control configuration a little less ‘ghetto’?  Let’s see what we can do!

This instrument is really top-drawer.  Bound neck and headstock, gold hardware, totally pimped out!  The body is thinner, partially hollow, and the back of the instrument is contoured to feel a little more comfortable.


Here’s the rub.  The coil splitting duties are performed by this mini-toggle switch, which takes the place of the second tone control.  The owner wanted the ergonomics of the Custom Lite instrument but with two tone controls.


The control cavity is under this plate.


To simulate single coils, one side of each pickup coil is grounded.  The ground wire has yellow insulation.


With one tone control to rule them all, this little blue capacitor and the control under it is the whole tone circuit.


This pic just documents the bridge ground wire.  None of this needs to be altered.


If you compare this control cavity with other Les Pauls, you can see that it is much shallower, because the body is thinner.  Otherwise, it is not hard to visualize a two-volume, two-tone setup here.


To preserve the ability to go single-coil, a tone control with a push-pull pot is evaluated.  Here, a drawing is made of the actual cross-section of the guitar body at the instrument cavity, and the exact dimensions of the push-pull pot is recorded in the notebook.  Making this modification fit properly will require some careful gun-smithing.


The center of the hole where the mini-toggle switch originally lived is in the correct location for the second tone control.  Here, a stepped bit is used to carefully enlarge the bore in the body to accommodate the push-pull pot.


The inside of the hole is cleaned up a bit with the stepped bit.  The loose wires are taped out of the way and the finish on the guitar is protected with blue low-tack painters’ tape.


The bare maple exposed by the stepped bit is refinished with some appropriate stuff.


Pushing on the felt tip of the pen dispenses black lacquer.  This step is not entirely necessary, because none of this will be visible, but there is no sense in leaving bare wood exposed to Houston humidity.  And I’m OCD.


The threaded portion of the push-pull pot is long enough to work in a Les Paul body.  However, the switch portion is nearly too long to fit under the control cover.  Likewise, we will use another nut to get the control knob height to match the height of the other three knobs.  We have some fiddlin’ ahead of us.


The three bent leads on the potentiometer were bent a little more to keep them away from the edge of the spot-faced recess in the body.  You can see this by comparing this picture to the previous one.


This tang provides mechanical support for those instances when this particular switch is used on a printed circuit board.  But, it extends past the end of the switch.  So, it has to go.


The tang is gone.  The two fingers that hold the end of the switch housing in place were pressed down.  This is about as compact as I can make this assembly.


The paint is dry!


The switched potentiometer is mounted, and the height of the shaft is adjusted so that, when the knob is installed, it will appear at the same height as the rest of them.


The owner wanted the vintage ’50s wiring for this instrument.  Already, we are about 3/4ths there.


This horrible solder joint was almost certainly done at the factory.  I can’t let this go out of the shop like this!


These orange 0.022uF caps are just the thing to match the 50’s wiring esthetic.


To tie the switched potentiometer body to common ground, I am soldering the ground wire to the interface between the pot and the switch.  That is a weak place that can use all the support it can get.  Just looking at the long haul, folks.


The yellow ground wire is added, and the original switched wires from the pickup windings were transferred to this switch.


Now this looks more like a 50’s Les Paul wiring cavity.  No circuit boards here!  The cavity cover fits without interference.


More OCD-ness.  The output jack stuck out too far.  These washers were redistributed and a nut added inside.  I feel better now.


Does this look factory?  Mission accomplished.


This Cragislist instrument is a real winner!


Thanks for reading all the way to the end!

CONTACT – David Latchaw EE

JR Beck Six String Bass Blend Pot Adventure

Billy said that he really liked this bass, but the blend pot was coming loose and something electrical was intermittent inside the instrument. Could The Unbrokenstring Crew look it over and make it stage-worthy again?

In literary circles, the term “vanity publishing” is often applied to authors who self-publish their own works. The JR Beck line is a ‘vanity-built’ line of musical instruments, wherein an individual approaches an instrument manufacturer to build instruments under a new name. This bass likely came into the world as part of a contract with a Korean manufacturer.


The neck is straight and the frets are level.  This is a player’s six string bass.


The head stock shape reminds me of an Ibanez profile.


The Grover tuners are really nice.


Someone has been here before.  This screw is too long for the hole.


Just how deep does the hole need to be?  It needs to be THIS long.


We will bore this hole down to the tape go get the length we want.


I can find no markings on the preamp electronics.  The rest of the wiring is a mess around the blend pot.


The duct tape did NOT come from Korea.  Why not get someone who can do this sort of work cleanly, like me?


The blend pot is a hack job.  The rest of the wiring is probably as it was from the factory.


Use more solder if you don’t solder it right the first time.  The solder has actually flowed inside the unit and mechanically interferes with the rotation of the wiper in one of the sections of the control.


We’ve removed the wires from the blend pot.  The cables with the green and yellow jacket come from the pickups. The cable with the white jacket wire goes to the active electronics.


Some RTV was used in an attempt to stabilize the front face of the blend control and keep it from moving when the knob was twisted.  What a mess.


As the control moved around, it scored up the wood body of the bass.  No pick guard on this unit.


To stabilize the wood and prep to mount a new control in a stable manner, a Forstner bit is employed to create a flat-bottomed ‘spot face’ in the wood cavity.  There is some risk of penetration, so we’re going slowly at this point.


A flat-bottom hole is bored without incident.  A steel washer will be epoxied into the body to fully-support the new blend pot.


The new blend pot comes with a couple of flat washers.  I’ll use a lock washer and another nut to set the height of the control so that the knobs are all installed at the same height on the face of the guitar.


A blend pot is a pair of “M” taper potentiometers, which allow one pickup to be faded out as the other side gets louder.  As the control reaches each limit of its travel, the other pickup is electrically ‘cut out’ of the circuit.  In a way, it acts as a selector switch at each end of the travel, with a continuous blend of the two signals in between.


The cross wiring is done with solid 20AWG copper covered with Teflon tubing.  The pickups are wired on the end.


This control has an index pin.  We will cut a slot in the steel washer to ‘catch’ this index pin and hold everything in place.


Initial tests showed that the signals from both pickups were literally ‘grounded’ when the control was set to either limit.  We need to install range-limiting resistors to each end of the controls so that the selected pickup is not grounded at the end of the potentiometer travel.  This is a blend pot, not a kill switch, after all.


It is an easy task to break the connection to ground and install a fixed resistor.  The proper value depends, in part, on the internal DC resistance of each pickup.  It will be easier to discover the proper value empirically.


The box with all the switches is sometimes called a ‘design box.’  The proper name is a ‘resistance substitution box.’  Various values of resistors are switched into the circuit until the desired result is obtained.  Here, we are choosing a resistor value for one side of the blend pot.  Too low a value attenuates the signal.  Too high a value causes hum.


Here is the fixed resistor for this side of the blend pot.  Note the use of the Teflon tubing to keep the signals under control.


Here is the new control installed in its new home.  I am satisfied with the electrical results of this experiment.


The original knob works nicely with the new control.  Note that the knobs are all the same height off the body of the bass.  Another thing I like about this bass is, look at that massive bridge saddle and end block!  The Koreans really know how to do it right.


Jacob takes the finished bass for a spin.  He wants one!

Thanks for reading all the way to the end!

CONTACT – David Latchaw EE

The Prodigal Guitar – Harmony H80S Olympic Strat Comes Home to the Fortunate Son

Jason Becerra of Cathedral Records is our guest blogger today. He shares an incredible story about how this immaculate Harmony H80 Olympic Strat was won, was lost, and won again. Enjoy the trip!

“I was writing songs long before I could play an instrument. I had notebooks full of lyrics and I had melodies for each song.

“My parents, like many in that era, put me in piano/organ lessons at the mall where they bought a Lowery synth organ for me. I learned how to play ‘When the Saints Go Marching In’ with one hand and I have fond memories of the old woman whose pleasant teaching style was metered only by the not-so-faint aroma of liniment and hard candy. After my year-long course ended, I received my certificate of completion, and that was that.

“A couple years later though, my dad brought it home. “It” was a white on black Olympic Strat copy with a matching head stock. It was the coolest thing in our house and I, of course, was discouraged from messing with it because I had a track record for destroying guitars. When I was about 4, (and I have no recollection of this, I swear) I did my best Pete Townsend impersonation on my dad’s beloved acoustic guitar.

“By the mid-to-late 80s, he’d decided to get himself a new guitar, this time an awesome electric which was purchased, used, at a local pawn shop under the guidance of one of his many musician friends.  I was on a heavy diet of Elvis, Buddy Holly, Jerry Lee, Tommy James, Mamas and Papas, the Turtles, Dylan, Gary Lewis and the Playboys, Gerry and the Pacemakers and of course…the Beatles and the Beach Boys.

“Now, I don’t know if this was by design or by accident, but I experienced the music of the 50s and 60s in the same way my dad did, in terms of age and sequence.  When I was very young I was bathed in doo-wop and rockabilly that laid the foundation for rock and roll.  A bit later, I got to the early 60s: Motown, surf and folk rock, girl groups like the Shangri-Las. Then…the British Invasion hit me with the rabid, frantic pounding beat of the Beatles’ ‘She Loves You’ and Dave Clark Five’s ‘Glad All Over.’  As the music of the era matured and gave way to albums like the Beach Boys Today! and Pet Sounds and the Beatle’s Sgt. Pepper, I too was maturing and growing into myself.

“All the while, my friends (who thought I was more than a bit strange due to my obsession with our parents’ music) were feeding a steady stream of modern music; everything from Bon Jovi and Van Halen to the Cure, REM, Information Society, the Ramones, the Descendents and of course, being in high school at the time, the early 90s music scene hit me just as hard as anything.

“All the while, that black Olympic sat in my dad’s office…just begging me to come take it.

“By 8th grade I had grown frustrated with poetry, essays and stories.  I wanted to say more.  I had more to say, feelings I couldn’t convey without something… without MUSIC.

“One evening, I grabbed his guitar and a “Learn to Play Guitar with Mel Bay Level 1” book.  I studied the chord chart for “G” and struggled to get my fingers just right and after a little while I got all six notes to ring out.  It was magical.  I was sold.  From that point it has been a truly lifelong obsession and it all started with my dad’s Olympic that was generously handed down to me as he realized what he had created in me. Haha!

“I lugged that thing EVERYWHERE.  I knew every corner of it.  I learned how to clean it, how to change strings, how to tune it and I still vividly remember learning the changes to Yellow Submarine and thinking, “Holy Shit!!  I’m getting the hang of this!”

“In 1995, I graduated high school and got a little job while attending university. I saw a shiny new Fender Stratocaster hanging in a guitar shop in Pasadena, TX. I decided to get my first “proper” instrument. I loved it. It had a fancy-schmancy humbucker in the bridge and a Floyd Rose locking tremolo and even though it became my “main” guitar, I still went to the Olympic, all the time. There was something special about it, with its maple neck, the little nick at the 9th fret near the high E string.

“Over the years I had developed a desire to have the Olympic worked on.  The pickups were sounding awful, lots of buzz, the knobs and switch were rusted, machine heads were cheap import stuff and it didn’t hold its tune quite as well as it used to.  It was old when I got my hands on it and I had certainly put it through its paces so it was showing its age.  My friend soldered a random piece of wire onto the back of the guitar inside the cavity where the springs attach…onto the middle hook.  He said it would help with the hum…not so much but he had been playing longer than I, had a jam room in his garage, and owned a van.  Who was I to question?

“By the early 2000s, I was anxious to get someone to work on my Olympic.  I met a guy and I gave him the Olympic with a set of machine heads, a set of Fender hot vintage noiseless pickups, new knobs, and a new switch and asked him to do the work for me.  He said it would take a few weeks and he’d call me.

“Months went by…he stopped working at the store where I met him.  His phone stopped accepting calls.  Nine months go by and I get a random call from him saying he was sorry for being out of pocket but that he was almost finished.  I begged him to let me come get my guitar, no hard feelings; I just didn’t want to lose my guitar.  He assured me he would not fall off the grid and that he’d get in touch with me in a week or two.

“I never heard from him again.  That was 2003.

“For over 10 years, I scoured craigslist, EBay, Guitar Center, pawn shops, everywhere I could think of looking for this Olympic guitar.  No one had ever heard of them.  Truth be told, I had the only one I had ever seen!  No luck.  There is ONE post on a random website where a guy shows a picture of his red Olympic.

“I actually signed up for the discussion board and sent him a private message asking if he’d considering selling it.  No response.  My black Olympic Strat copy had become my unicorn.  Until a couple months ago…

“I was home sick, lying in bed with a nasty stomach bug.  I was looking at Craigslist for my guitar when all of the sudden, I saw one!  I immediately called the guy and said “I’m on my way.”

“I took another look at the guitar and my heart sunk…it wasn’t the same one.  This guy had a blue one…mine was black. Well crap.

“I told him to forget it.  For a couple weeks I was on the fence.  What if I never see another one?  Isn’t blue close enough?!  Am I ever really going to find MY guitar again?  Shouldn’t I just settle for the same model?  I decided to settle. What the hell.  I’d given up.

“I drove over to where the guy had the guitar and picked it up.  He was a nice older man who does garage sales to augment his retirement income.  I asked where he got and he didn’t really remember…his son got it from some guy.

“I took it home and was immediately plugged it in.  Nothing. It didn’t work.  Damn it.  All this and now I can’t even play it! But I stared at it…and I held it and I examined it.

“Curious…there’s a nick right at the high e-string,  9th fret. Hmm…

“The sticker with the “serial number” is scrunched up in the same way I scrunched mine up.  Wait…this guitar isn’t blue! This guitar is BLACK.  Someone put a blue coat of paint on this thing!

“Could it be? Naaaaaaaaaah.  What are the odds right?

“So I called my good friend David Latchaw to give this thing some love.

“While David is working on it, I go back on the trail.  I start posting on Facebook and I get a name of the guy I gave my guitar to in 2003.  I found him on Facebook…..and wouldn’t you know it, he’s “friends” with some friends of mine!  All these years, he’s been right freaking there!

“I reach out to him and he explains what happened all those years ago.  He stopped doing repair work and gave everything he had to an associate of his who was supposed to call customers and return the gear or finish the repairs. Now I had a NEW name.  I started hunting that guy down.  I found a trail of hacked or shut-down websites, bad reviews on forums about “what happened to that guy?  He used to do great work!  Now he’s fallen off the face of the earth!” Apparently this guy fell into some troubles, and that was that.

“But I know he had it and pretty much just sold everything he had to whoever wanted to pay for it.

“Could he be the guy that the old man’s son bought this guitar from?

“David comes back with my new (old?) Olympic and of course it plays like a million bucks.

“As we were talking I asked if he opened the back panel.  He says yeah. I ask what he found.

“He said, “darndest thing, someone had taken a piece of random wire and soldered it to the middle claw… I’ve seen this for grounding, but never on the center claw like that.  That’s a new one.”

“Well folks…long story short…sometimes, what goes around….really does come back around.

“I bought my original guitar 12 years after losing it…and didn’t even realize it until it was back home in my hands and David had worked his magic.  While it was away from me, the machines head actually got installed but the original pickups were left in.  I guess whoever down the line decided to use the pickups I bought on something else.  It also got a paintjob!

“David gets a huge thank you for all his incredible work on this guitar and all the previous work he’s done and the future work he’s going to do.  (I’m going to keep you busy my friend.)

“My wife gets a huge thank you for indulging my music obsession for all these years and never once putting her foot down when I say “I need to get this guitar” even though I always say that’s the last one I’m going to buy.

“My Dad gets the biggest thanks of all…for filling my childhood with music, for never hesitating to lend me his records, for always playing “name that tune” when we were in the car (he quit playing when he said I became better than him) and for the black pawnshop strat-copy Olympic guitar that started me on this little journey as a wannabe songwriter.

“I AM a fortunate son.

“My advice to all of you players out there…it might be tempting, but never let go of your gear. Don’t trade it, don’t sell it and don’t give it to anyone you don’t have 150% confidence in because you could come to regret it for years and years to come.”

Jason Becerra

You have heard the news. Now, here’s the rest of the story.

This head stock just oozes ‘vintage’ and we are not to be disappointed!

We need to replace the controls, including the switch.

Some of the bridge screw holes in the body were stripped, or the screws were missing.  This is an easy fix.

The correct screw for the bridge is an inch long.

We believe that this guitar was painted.  No shortcuts were found in the blue finish.

The original controls were shot.  These are the smaller, 16mm controls often seen on imported guitars.

This is a ‘treble bleed’ capacitor, which keeps the treble from disappearing as the volume control is dialed toward zero.

This is the tone capacitor, that works with the tone control to form an RC network that shapes the frequency response of the guitar.

The tone cap is a polyester film part that checks good.  We’ll use this part again when we reassemble the guitar.

The selector switch is shot.  Jason wants a switching arrangement that selects just the bridge pickup, the bridge and middle pickup, all three pickups, the middle and neck pickup, and finally just the neck pickup.  The factory switch won’t do that, so we’ll use a Super Switch in place of this unit.

The original single coil pickups are in excellent shape.  Each one is labelled with orientation and position.  Then, the pickup wiring is clipped cleanly from the controls.

These pickups will be reinstalled with the new controls.  For now, we will remove them and set them aside.

This is the new Super Switch.  We have a couple of issues.  One, the mounting holes in the Harmony pickguard do not align with the screw holes in the Super Switch.  Also, the lever slot in the pick guard needs to be longer to allow the switch to move fully through all five selector positions.

Here, I get an idea how long the slot in the pick guard needs to be.

This is how long the slot in the pick guard actually is.

Rather than remove a lot of material from a priceless pick guard, we can narrow the selector arm on the switch to not take up quite so much room in the pick guard slot.

Here, I’m reshaping the selector arm on the switch with a mill file.

If you compare this pic to an earlier picture, you can see the material removed from the arm of the switch.

Rather than drill new holes in the pick guard, I’m locating the centers of the existing pick guard holes on the body of the Super Switch.  Again, I do not want to modify the vintage pick guard if I can help it.

The center punched locations of the pick guard holes were drilled for a 4-40 tapped hole.

Here we can see how the new mounting holes are located with respect to the old ones on the outside ends of the switch.

The holes are tapped to match the mounting screws.

I think this is going to work well for us.

The new switch is trial-fitted to the pick guard.  The length of the mounting screws is examined closely to see if they interfere with the action of the Super Switch.

The ends of the slot for the switch were ever-so-slightly widened to allow the switch lever to move fully to each position.  Here, I’m using a guitar nut file for a low E string to shape the slot.

The heads of the new mounting screws were turned down slightly to allow the switch arm to clear.

We have full switch travel from end to end.  This will work well for us!

The potentiometer mounting holes were widened to 3/8ths of an inch to match the bushing diameter on the new controls.

The new controls are full-sized 24mm parts intended for vintage Fender Stratocasters.  This one fits ‘just right.’  I went with 250k pots because the guitar would be very bright-sounding using the original tone cap and 500k pots.

Here are the new controls, set to the proper shaft length for the Fender knobs.

These are all 24mm controls, so I verified that they would fit in the original body routes.  They do!

I stripped off the aluminum shield tape.

I replaced the shield tape with copper.

Using the copper tape, I could now tie the body of the pickups to the same shield as the controls.

The copper solders quickly, without melting the pick guard underneath it.  This ensures that the copper plane is continuous.

Here is the new mechanical layout of the pick guard.

With the new controls mounted in place, the wiring scheme for the five-way switching could be implemented.

The gray cables come from the pickups, and are wired to terminals on the Super Switch.

Wiring for the volume and tone controls is done with solid silver-plated 26AWG copper, covered with aerospace-rated Teflon tubing.  Much of the Space Shuttle Orbiter electronics are wired this way.

This is the finished pick guard assembly.

The output jack wiring, bridge ground wire, and tremolo claw wiring (such as it is) are already attached.  The bridge is set up as a hard tail (no tremolo arm needed.)

The setup and fret polish went pretty well.

Now we have returned, full circle, to where we started. This is an EXCEPTIONAL instrument!

Support Jason’s record label!

Jason’s father Rolando is still making music and making an impact on the music world today. His radio program “Branson Now,” airs on AM700 KSEV in the Houston market. Rolando brings a unique narrative to the rich world of music as only someone of his experience and sensitivity can do.

Click here to see more about Rolando Becerra’s radio program in Houston!

Thanks for reading all the way to the end!

Contact – David Latchaw EE
Cell – 281-636-8626

How Gibson Les Pauls Lose Their GForce Tuners

I own several old Gibson guitars , so I am only passively interested in, and mildly amused at, the flame war over the self-tuning GForce system included on new Les Paul guitars.

Jacob of The Unbrokenstring Crew said “The Internet is where nuance goes off to die.” Like most topics of discussion, the flame wars over the Gibson GForce system has devolved into a bipolar, binary love/hate relationship. Perhaps, someone actually thought about the situation, and decided that they would sell more guitars WITHOUT the GForce system installed. To that end, our local national guitar retailer has received some interesting tool in the mail.

These blocks of steel have nylon alignment pins that fit in the factory tuner holes used by the GForce system. The small holes are where the headstock will be drilled for manual tuners of various makes and models.  The Klouson holes are in the wrong place, so we are only installing Grover tuners for now.

Here is the back of a Les Paul headstock with the GForce system removed. Except for the indentations in the wood where the printed circuit board traces were, you would never know that they were there… more or less…

The GForce tuner assemblies were removed from the headstock. These are to be returned to the Global Headquarters of the National Guitar Retail Chain when we are through.

Perhaps they will salvage the rechargeable batteries, or maybe they will be used for spares as these fail in the future on other guitars. Hey, it could happen!

The nylon alignment pins hold the template in place. Drilling a hole and installing new manual tuners is straight-forward.

Grover tuners, anyone?

How about some locking Grover tuners?

For the purists, here are some Klusons on an older guitar.

I will not weigh in on the flame war over the deployment of the GForce system. But now you can go to a retail outlet and find a 2015 Les Paul that does not have the GForce system installed. We’ll see how this decision plays out over the coming years.

Thanks for reading all the way to the bottom!

Contact – David Latchaw EE
Cell – 281-636-8626

Ibanez Bass Fretless Conversion

This straight-ahead Ibanez four-string bass will become a springboard for a bassist to expand his musical horizons. Can the Unbrokenstring Crew turn this into a fretless bass? Let’s find out!

Because this will be a training tool and not a piece of performance art, the customer wanted the fret channels and position dots to remain visible.  Maple, a contrasting wood will fill the fret slots.  The maple veneer is coiled up in the yellow box next to the bass.

We’ll take one last look at the frets.  Say goodbye!

These strings are the original OEM Malaysian strings.  These are headed for the recycle bin.  The customer also asked that the headstock logo be removed, to add a little mystique.  The tuners will be removed and stored.

The tape protects the fret board from me.  An Exacto knife clears away the junk from the bottom of the fret to be removed so we can have something to grab.

With a little care, the Exacto knife blade can be pushed under the fret wire to start the removal process.  Do Not Attempt This At Home, Kids!

Each fret is heated with the soldering iron.

These Harbor Freight end-nippers have been ground flush and serve as a pretty good set of fret pullers.

What the Exacto knife started, the fret puller finishes.

This takes a few moments so that I don’t tear out the wood around the fret tang.

Houston, we are clear the tower.  Rinse, repeat.

These are headed for the recycle bin, along with the strings.

Some Dr. Ducks Ax Wax has just enough petroleum distillates to cut the headstock silkscreen.

The head stock logo yields easily to a little Dr. Duck’s and a little Elbow Grease.

A tiny bit of compound restores the gloss in an even manner.  You can’t tell the silk screen was ever there.

Say goodbye to the identification decal, too.  What the customer wants, the customer gets!

This was a decal, so it shattered into tiny fragments.  Be sure to remember this trick when you steal your next guitar.

Now we move to the maple veneer.  The material we are using is sold as edging around laminate counter tops.  One face is covered with a thermally-sensitive glue.  This glue can be easily removed with some paint stripper.

The stripper was brushed on, then scraped off.  This is kinda fun!

After the paint remover evaporates, we cut the veneer into two and a half inch long strips.

The bottom of the fret board slots are curved at the same radius as the fret board.  So I am using this home-made radius gauge as a cutting guide to radius the bottom edge of the maple veneer to match the bottom of the slot.

An Exacto knife makes short work of the veneer.  You sharp eyed visitors may note that the Ibanez bass fret board is 14 inch radius, not 13.  Leaving the center a little high allows a place for more glue.  This radius works perfectly.

As one edge is cut, the veneer is slipped out from under the radius gauge, and another cut is made.

The fret slots need to be clean and straight.  Here, my scraper is just the right size to clear out the slot.

The ends of this scraper were ground square, creating a nice slot cleaner.

The radiused maple veneer pieces were glued into the slots using hide glue.

This looks like an oriental stringed instrument neck.

After the glue dried, I used the end nippers to do most of the coarse trimming.  A fret board protector acts as a shim to raise the cutting edges off the face of the fret board.

Next, I’m trying out the Exacto knife on the maple.  Nice curly shavings came off the maple filler.

Working from the center of the fret board out, the single edged razor blade was perfect for the final smooth cut.  Note that a bit of the glue fillet is being removed here, resulting in a nice flat surface on the fret board.

Here is a closeup of the job the razor blade did on the fret board.  This will sand nicely.  A final check of the truss rod assures that the fret board is held absolutely straight, no relief or bow of any sort.

This Stanley spirit level has one edge machined to a very precise flat surface.

This emery cloth is a very aggressive and durable abrasive medium.

A sheet of emery cloth was cut to fit the machined edge of the spirit level.  Now we’re ready to build our own sanding beam.

The emery cloth will take at least two coats of contact cement because the first coat soaks into the cloth.

In case you missed the first one, here is the second coat of contact adhesive

The strips of emery cloth form a continuous abrasive surface along the entire length of the spirit level.

This heavy aluminum fret board gauge is just right to mash out all the air underneath the emery cloth.

The spirit level makes a sanding beam that is the perfect length for this bass fret board.  See the dust at the right end?

Now that the fret board is straight, we will reestablish the radius of the fret board with this 14 inch radius sanding block.

Radiused and straightened, we’re ready to apply a hard finish to the fret board.  Everything that is not fret board is covered with tape.  If you hadn’t noticed, the nut was removed prior to sanding.

I didn’t want to put much finish on the end grain at either end of the fret board in order to minimize any swelling or expansion that would spoil the shape of the fret board.  When the wood is sealed, I’ll go back and finish the end grain.

The unlabelled can contains Diamond Varathane Floor Finish, a commercial polyurethane finish used in roller rinks and bowling alleys.  I discovered this stuff when finishing pine furniture.  The Diamond Varathane was the only thing that would stand up to my cat’s desire to chew on the corners of the furniture.  Absolutely bullet-proof.

The first ten (yes, that’s TEN) coats were applied with a brush.  We are filling a lot of wood pores, you know.

The radiused sanding block gets quite a workout, starting with 80 grit, then moving finer.  This is 220 grit.  The tiny dimples around the fret slots are filling in with each coat of Diamond Varathane.  Ten coats were applied and sanded to radius over a period of nineteen days.

For the final finish process, the next five coats of Diamond Varathane are applied with an airbrush.  Here, the Diamond Varathane is thinned slightly with distilled water.

Thanks to my Darling Bride, this stirring moment in history will be preserved forever.

A plastic soda straw makes a nice disposable pipette to transfer the finish to the airbrush reservoir.

We’re loaded.  Not much finish is needed for the final coats.

Everything is assembled.  This little air brush comes from Harbor Freight, and is surprisingly good quality for cheap ChiCom junk usually found there.  The air and the flow of material is easily controlled on the fly, while you spray.

We are experiencing technical difficulties.  One moment, please, while we display a Test Pattern.

The sprayed finish goes on much more smoothly than a brushed coat, which is why I switched to the airbrush for the last five coats.

Now this is beginning to look like a fine musical instrument!

The exposed edges of the maple fret veneer is sealed with some Diamond Varathane as well.

For the last two coats, I also sealed the end grain of the fret board.

One coat on the fret board does not require much finish.

The last five coats were wet sanded.  Three coats were radius sanded with 400 grit paper, the last two with 1000 grit.

A little rain water was spritzed on the work piece.

Keeping the sandpaper wet is a good way to keep material from building up and clogging the sandpaper.

Wet Sanding At It’s Finest!

Tiny bits of the Diamond Varathane are floated away in the wet sanding process.

Thus begins the final sanding session, 1000 grit wet.  Very little material is actually removed.  This is just surface prep.

Here is the fret board after the final sanding and dry-off.

This is fifteen coats of Diamond Varathane, rubbed with a cotton cloth to bring out the shine.

Here is a nicer view of the hand-rubbed finish, with reflections courtesy of Mr. Brewster Angle.

Off comes the tape.  A tiny bit of wet sanding and rubbing is used to smooth the edge of the finish so that it blends into the original finish on the back of the neck.

Time for tuners!

Some folks can artificially age guitars with ultraviolet light to remove these ‘tan lines’ but I don’t do that.

Warning – Guitar Porn.

Oops, I need to remove some fingerprints on this side.  The nut is glued back on and we’re ready to reattach the neck to the body.

The action is, of course, WAY too high now that the frets are gone.

These strings are about 0.056 inch off the fret board at fret one.

As a sanity check, this gauge shows the same measurement.  This is a nice closeup of the finish on the neck.  The Diamond Varathane is absolutely rock-hard after curing.

I put this 0.022 inch feeler gauge under the string slots, then proceeded to deepen the slots to just touch the gauge.

Here is the A string file at work.

The plastic nut flows a bit when worked.  An Exacto knife trims away the flash.

Time to take any sharp edges off the nut.  Playing a fretless bass is all about the “feel,” after all.  After a neck shim and a simple setup at the bridge, this bass is ready to mwah.


Thanks for reading all the way to the end of this long post!

CONTACT – David Latchaw  EE


Ex-GF Smashes Jackson Guitar

Can’t live with them, can’t live without them. A late-night call was the starting point of the end of a relationship between a young man and his guitar. His prized Jackson was smashed by a cray-cray now-ex-girlfriend, and his new squeeze sported dull, boring factory pickups. Could the Unbrokenstring Crew salvage anything from what had been broken, and spice-up the rebound relationship?

Here is most of what was left of the Jackson.  These pickups sounded pretty cool with his rig, so he wanted a pup transplant.  Beyond the bridge, strap buttons, switches, and maybe the neck, this guitar was now firewood.

I’m not into Jackson guitars, but that is some unusual artwork.  Maybe a fake?

Now this is a purty guitar!  Hope his new girlfriend isn’t the jealous type.

The neck pickup of the Jackson is a DiMarzio Evolution.  It measures about 13k ohms.

Yep, it’s an Evolution.  Steve Vai, anyone?

I’ll give you three guesses who made this Custom Custom pickup.  However, it is a tight fit for that trim ring because the trim ring is pulling the tape off the windings.  I can fix that.

The coils read 14.4k ohms, which tells me these are OK despite the rubbing damage.  Lidia Daniels wound this pickup!

This selector switch is OK but not needed today.  I’ll clean it up and return it to the customer.  What a hack job!

One of the broken pieces has this cut-out switch.  I’m not going to route the new guitar to add this button today.

We’ll clean this up too and return it to the customer.  The blue button would look ‘cheap’ on the deep red guitar.

The cadaver is ready for the body bag.  The police can clean up the crime scene.  Our job here is done.

The bridge pickup trim ring was scraping against the insulation on the windings.  A Dremel tool with a sanding drum created some space in order to set the pickup height properly.

However, the pickup height could not be set because a screw and a spring was missing.  I just happen to have here, in my formerly-nicotine-stained fingers, some left-over hardware from another pickup installation.

From this angle, you can see the bump in the pickup windings, and the clearance for the bump carved into the ring.

Yeah, that’s better.  Not too shabby-looking, either, after a quick buff and polish.

The factory pickups in this LTD F50 work fine, and will be removed and returned to the customer.  I have marked them N for neck and B for bridge.

We’re going in!  Everything here seems to be in order.  The pickup wiring goes straight to the selector switch.  Easy!

This is the DiMarzio in its new home.

All the wiring is pulled through the routes in the body.  The guitar is starting to look snazzy!

This does not look a whole lot different than it did before I started.

Pimp My Ride!  Y’all have seen new strings and a setup before, so we’re done with this blog.  One relationship ended, and another one begun.  BTW this guitar sounded FANTASTIC in the hands of the owner!


Thanks for reading all the way to the bottom!

Contact:  David Latchaw  EE


New Seymour Duncan Pickups for an ESP LTD

Experimenting with various pieces of gear is one aspect of the guitar hobby that appeals to most players.  This Indonesian-built ESP would benefit from some after-market modifications.  Here We Go!

This is not a bad guitar, and is surprisingly easy to play despite it’s flying-Vee shape.

What the customer wants, the customer gets!  These will fit right in to the guitar without any modification.

As you can see, this guitar is strung through the body.  If you look closely, you can see that the string saddles are all going the same direction.  From a practical point of view, this doesn’t make much difference as long as the intonation can be set properly, but many an Internet flame war has been waged over the ‘correct’ saddle orientation.  Spare me.

These are the original factory pickups.  They work fine, and will be saved and returned to the customer.

The main work will happen underneath this cover.  All of the wiring is terminated here.

The original electronics are just fine.  I’ll cut the tie-wrap and sort out where the existing pickups are wired.

Both pickups are wired directly to the selector switch.  The red cable is the neck pickup.

Note that the trim screws are different length.  Knowing which screw goes where will be important when putting everything back together.

We are liberating the the neck pickup and trim ring.  Note the red insulation.

The cable to the bridge pickup is covered in black insulation.  Note the common passage that both cables use on their journey to the wiring cavity, accessible from the back.

Houston, we are clear the launch tower.

The original pickups were stored in the same container in which the new pickups were delivered.  And, because I’m forgetful, I made a note about which one was which.

I clipped the wires in order to remove the old pickups.  The solder sucker is clearing away the terminal where the neck pickup was wired.

Now we’re cleaning up where the new bridge pickup will be soldered.

All the shields were wired together and attached to the body of the selector switch.  Here, I’m cleaning this up so that a new solder connection to the shielding braid can be made.

With all the hardware off, this might be a real good time to clean everything up, don’t you think?

That’s better!  Oops, I did it again…  Guitar Porn!

The Seymour Duncan pickups were wired for split coil operation, but we’re not using that option today.  Thus, the two halves are soldered together, as shown here.

Heat shrinkable tubing insulates and protects the splice.

The original pickup trim rings are cleaned up and polished.

Can you guess which one is the neck pickup trim ring and which one is the bridge pickup trim ring?

With a little patience, the new pickups are integrated into the trim rings using the springs and screws provided.

Here, I’ve snaked the neck pickup cable through the body of the guitar.

And as we saw earlier, the cable passes through the bridge pickup route and onward into the electronics cavity.

I’ll use a couple of the trim ring screws to temporarily keep things in place.

Same with the bridge pickup.

The new cables were soldered where the old pickup cables were originally installed, and a fresh tie-wrap will keep things under control.  We’re done here.

Now that the guitar is closed up, it’s time for a little Fret Love.

We’re all set up and ready to play!

Jacob does a final test on the electronics and guitar action.  He was pleasantly surprised that such a radical-looking guitar could be so easy and fun to play!  Good Job, Unbroken String Crew!


Thanks for reading all the way to the bottom.  More Guitar Porn to come!

David Latchaw  EE


First Act “Discovery” Kid’s Guitar from WallyWorld, Back From The Trash

This toy guitar has a built-in amplifier and speaker.  Although not a ‘serious’ instrument, I readily agreed to check this little guitar out for a friend.  Yes, they literally found it in the trash.

Now, before you Gear Snobs click your tongue at anyone who would be interested in spending any time with this guitar, there are tens of thousands of three-quarter and seven-eights scale guitars sold each year, and a few hundred half-scale guitars.  The youth market requires down-sized guitars for little people who don’t have the arm strength or finger length to support a full-sized guitar.

The only concern I had was, could the guitar be playable, have good intonation, and could it make music in such a way that would not discourage a potential future musician?  Undeterred by your definition of “making music,” the Unbroken String Crew jumps to work!

So the mushroom-shaped plastic covers keep the sharp string ends from harming the little kiddies.  The string tree is cool.  The deep slots in the plastic nut are pretty standard for cheap Chinese guitars.  What is wrong with those people, anyway?

I’m a little surprised that these open-gear tuners would ‘fly’ past the product safety people.  Isn’t this a pinch hazard?

The battery under this cover runs a built-in amplifier.  No buckle rash here (or maybe I should say, no safety pin rash.)

The amplifier works!  Plugging in a set of headphones mutes the built-in speaker.

The bridge and saddle are one piece, and there is no adjustment for string height.  Likewise, whatever the pickup height is, is what the pickup height is.  This is just a toy, but now I’m a little worried that the setup will not go well.

The headstock needs some work.  Here is another view of the tuner capstans, with the protective string covers out of the way for now.  These plastic covers double as bushings.

Stamped steel tuners meet the price point of this toy guitar.  But they are functional.

Here you can see what passes for bushings around the capstans.  This can go into the sink for cleanup.

Maybe this is dried catsup?  Ewww…

Dried catsup is easy to remove with a scraper, as any parent can tell you.

The very end of the headstock was dinged up during the guitar’s trip through the dumpster.  As there is no need for preserving the VOS (vintage original specs) of the headstock, I’m sanding away with 80 grit.

A little clear polyurethane will seal up the wound.

Other than the dried catsup, there’s nothing wrong with the finish.

And there was more dried catsup on the fingerboard, but that’s all gone now.  A little fret polish, perhaps?

Tuners were disassembled, cleaned, lubricated, and reassembled.  Not bad for stamped steel.

Surprisingly, the gear lash and tooth mesh were both manageable.  A little LokTite and we’re good to go!

All strung up and, surprisingly, fairly well set up.  If I were to spend more time with this guitar, I would grind off some of the nut plastic to better define the string seats, but for now, I’ll leave it the way it came from China.

Every adult who has picked up this guitar has smiled as they played it.  I’m still not sure that the young lady for whom this was promised has seen it yet!


Thanks for reading all the way to the bottom!

David Latchaw EE


Custom Built Paul Reed Smith McCarty Standard

A friend of a friend had this beautiful Paul Reed Smith McCarty guitar refinished with an even more beautiful black finish. But, he encountered some difficulties putting it back together, and wanted me to look at his baby.

Everything had been buffed to better-than-new condition.  Some polishing compound remained as you can see here.

But some paint had dripped into the threaded bushings, and the owner was concerned that he would only damage the new finish more while trying to build this guitar.  So he called in The Unbrokenstring Crew!













We had a big bag of parts and a guitar body in a case.  Let’s get to work!

05CleanThreadsThe chip was touched up, then allowed to cure for a week.  Now, we’re protecting the finish of the guitar so that we can chase the threads in the insert.  I had considered just changing the inserts but didn’t want to take the risk at this point.

06TestThreadsAfter the threads were chased, a little bit of solvent was used to clear the bottom few threads.  Lots of protective, non-stick tape comes in handy when protecting a priceless guitar body!

07AjackThis is a nice shot of the new pre-wired jack, already attached to the jack plate.  The cabling was pulled all the way into the internal routed cavities of the guitar, where it would be attached to the selector switch.

07BjackOops, there I did it again.  A little Guitar Tech Porn!  This is a nice setup, regardless of whether you are a tech or not.

07CjackAll squared away.  On to the pickups.

08PolishPickupsOriginally, I thought that the hardware for this guitar was nickel.  However, these were used pickups, and had years of funk on them.  I made the executive decision that these should be shiny, because the rest of the guitar was shiny.

09PickupAssyYeah, that’s what I’m talking about!  By the way, treble pickups go closest to the bridge, and bass pickups go near the neck.  Which begs the question, what are the middle pickups in a three-pickup-guitar called?  Grand Staff?

10TempHoldThe pickups were temporarily held in place with this no-mar tape while the guitar was turned over to do soldering on the routed compartment on the back side.

11Wiring1The wiring diagram says that the taps go to the push-pull pot.  I added some heat shrinkable tubing to all the solder joints I made.  Too bad the factory doesn’t do this, because accidental shorts would be one less thing to worry about.

11Wiring2Here, the switch is wired up with the output leads from each pickup per the wiring diagram.

12FinalAssyWith everything wired up and working, the pickups could be fastened down.  See my earlier Jazzmaster posts about the method I use to check guitar wiring without any strings attached to the guitar.

13AssembleTuners1And now, off to the headstock.  These bushings were too tight to fit into the holes because of the additional layer of paint.  Each hole was hand-reamed until the bushings could be pressed into place.

13AssembleTuners2These tulip tuners give a Kluson vintage look to the guitar.  I just love the mahogany wood!

13AssembleTuners3More Guitar Tech porn.  We’re done with the headstock.

14BridgeThis TonePros bridge is an intelligent upgrade for wrap-around bridges.  Here, I’ve run the individual saddles to the far end of each string, so that the vibrating part of the string will always be straight and not deformed because it once was bent over a saddle.  We’re ready for strings!

15DoneThis guitar has a beautiful voice, and the owner was pleased with the results!  Oops, more Guitar Tech Porn!


Thanks for reading all the way to the bottom of this post!

David Latchaw