Guitar and Mandolin Repairs : Kalamazoo Mandolin





This lovely old ‘30s Kalamazoo came into the workshop because it has a problem with its action.

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The action is very high and it’s not too long before the reason for this high action is spotted.

The neck is pulling up with the tension of the strings and a gap has appeared at the neck/body join.

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According to its owner it had been attended to in the past but the repairer merely forced glue into the join, applied clamps and hoped for the best. Consequently over time the join has failed again.

The only means of dealing with this type of issue is to remove the neck and to make an assessment of the internal join.



The fingerboard extension is heated to release the glue. By teasing a little warm water into the join the hide glue is softened and the neck join becomes undone.

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The neck and body are held together with a simple French Dovetail. On close inspection of the dovetail it appears that it does not reach to its full height.

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It is decided that a simple solution would be to extend the male half of the dovetail.

The end is trimmed down and a piece of Mahogany glued into place.

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As a safeguard an Ebony dowel is fashioned and inserted down through the body of the join.

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Veneer shims are added to the dovetail to ensure a snug fit.

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The join is assembled using hide glue and clamped.

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A few days later the mandolin is strung up, tuned and tested. The join is now gap free and the playing action is as it should be.

Click photo for Flickr pic set

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This lovely old mandolin has the beautiful tone of a mature instrument with the playability of a new mandolin, good for another 80 years!





Acoustic Guitar Repair: Vintage Epiphone Texan Neck Re-set







This lovely old Epiphone Texan was made in 1951.

The Guitar was taken into the workshop for some major repair work. It has many problems: a split in the soundboard, loose soundboard , loose bindings, fret wear, high action and intonation problems.

 

History in Brief

The Texan was produced by the Epiphone Company starting in 1942. After Epiphone folded, the Gibson Company produced the Texan in Kalamazoo Michigan until 1970. There have been numerous reissues of the Texan since their primary production period in the 1960’s. More here…

The Players

The Texan was made popular by Sir Paul McCartney for the recording and the live performances of the hit song from 1965 “Yesterday”. It is also famous for being the acoustic guitar on which McCartney performed the signature “McCartney Picking” in some album pieces such as “Blackbird”, “Mother Nature’s Son” (The Beatles “White Album”), “Calico Skies”( Flaming Pie), and more recently “Jenny Wren” (Chaos and Creation in the Backyard). Kurt Cobain of Nirvana used an Epiphone Texan on the 1994 In Utero tour. Also, Graham Nash used an early customized black (originally “cherryburst”) Epiphone Texan while in The Hollies and during the beginnings of Crosby, Stills, Nash and Young. Other artists with which the Texan is identified are Tom Rush, Al Stewart, Noel Gallagher and Peter Frampton. More here…



This straight-edge reveals where the string height should be

 

On a budget guitar the financially viable option would be to plane down the top of the bridge and set the saddle groove and saddle lower. However, on this valuable vintage instrument such an invasive repair is not an option. The only course of action is to remove the neck and reset at the appropriate angle.

It was also noted, in the initial work-bench examination, that the neck was positioned incorrectly for accurate intonation, another reason to remove the neck.

 

 


To reset a neck on any acoustic guitar is a complicated and difficult procedure.

Firstly the 15th fret is removed

Two small holes are drilled into the slot of the 15th fret (at a slight angle). These holes will allow steam to be forced into the neck’s dove-tail join. The 15th fret is approximately situated over the space between the female part of the dove-tail on the body and the male part on the neck.

The lacquer around the heel is scored with a sharp blade, to stop lacquer break-out when the neck is removed.

The fingerboard extension is heated. This softens the glue and allows it to be separated from the top of the guitar.

With the help of this neck removal jig the neck is safely removed.

A calculation is made using the “Neck Re-set Formula”. This allows the exact amount to be removed from the heel (for the correct neck angle) to be accurately determined.

A further adjustment is made to the tenon, heel and shoulder to shorten the string length and allow for correct intonation.

Two Rosewood dowels are made up to fill the two small holes drilled into the fingerboard.

The 15th fret is replaced and a hone and re-profile to all frets carried out to remove all fret wear.

With the neck angle adjusted the neck is firstly checked for proper string alignment relative to the horizontal plane and centre line.

The neck is glued in place using reversible Hide glue.

The soundboard split is cured and loose binding reattached.

The Texan is strung up with D’Addario 12 – 54 strings.

It plays and sounds fantastic and would be a treasured addition to anyone’s collection

Follow this link for enlarged photos on flickr…







 

 

With the help of this neck removal jig the neck is safely removed.

Bass Guitar Repairs London: Vintage Washburn B-20 Bass


One of my regular customers, and a collector of rare and unusual bass guitars, bought this Vintage Washburn B-20 bass into the workshop. He had hoped that it might be resurrected.

The immediate problems were:
•    Heavy fret wear
•    The electrics were in disarray with parts broken and missing
•    Machine heads missing
•    Nut missing
•    The Finish was scratched and battered

All in all it was a mess, after a workbench examination it became clear that most of the jobs were doable but there was one nagging problem, there was an extreme split to the back of the neck.

A major worry as this meant that this guitar was destined for the scrap-heap if this couldn’t be resolved. It appeared that the truss-rod was trying to burst out through the back of the neck.

This truss-rod problem could have been due to: (1) Faulty manufacture or material (2) A sudden shock to the back of the neck (3) A fault with the playing action that necessitated the truss-rod being tighten beyond its limit. Whatever the reason I needed to investigate further.

After a quick test I discovered that the adjuster was locked as tight as possible but the neck was in an upward bow. It was the  truss rod type that adjusted with an allen key and it showed signs of heavy use.
Another test would have been to string the guitar up, slowly bring the strings up to concert pitch and to check how the neck responded, but that was not possible as two of the machine heads and the nut were missing.

I decided to make an extreme adjustment test to the neck and truss-rod.

Using a heavy-duty straight-edge, blocks of wood placed at either end of the neck and a clamp at the centre of the straight-edge, the neck was gently forced back into a back bow. This took the strain off of the truss rod and held the neck in a back bow. With the truss rod under no pressure from the neck I was able to tighten the adjuster further to hold the neck in a back bow with the truss-rod. The splits seemed no worse for this action.
With the neck now held in a new profile, correct adjustment was guaranteed when it came to setting up the guitar. The tension could be slowly released, at the adjuster, until the optimum position was reached.  But first the cracking and splitting to the back of the neck would need to be remedied

The finish around the Mahogany insert was scraped back and the cracked insert routed out. This left a straight and clean channel for the replacement. This was to be a piece of ebony because of its strength and density (taking no chances here).

From left to right:

1. Neck held in jig

2. First router pass shows how deep cracks go

3. Third pass reveals truss-rod

4. Ebony inset glued in place

5. Cutting back the insert


As well as the neck repair here is a list of jobs that were carried out to bring this old War-Horse up to playing spec.

A Partial Re-fret

The frets showed signs of heavy wear and tear on the first 9 frets. These were replaced with identical fret wire. All frets were honed, re-profiled and polished


The Electrics

The pickups were working but the electrics were in a mess, components missing, bad solder joints and the components that were present were cheap and nasty. All pots, caps, 3-way toggle, jack socket and wiring were replaced and the pickups were giving a complete overhaul.


Machine Heads
New machine heads were sourced and bought in.


The Nut
A new nut was cut from a bone blank. How?…


The Finish
The Finish probably seemed worse than it actually was. The guitar’s top and back had what seemed like lines scratched into its surface. On closer inspection these weren’t scratches at all but gold pen and would probably polish out. Was someone, somewhere really considering cutting along these dotted lines?! There were many scratches and knocks all over its body. Although many of these would never polish out the owner resign himself to the guitar showing its “battle scars” and thought that it would probably look quite cool once the pen marks were removed and the finish polished up.


The Final Job

The last job was on the electrics back cover. This had curled up like a stale sandwich and would never go back into place without some attention.
I used my rib bending-iron and applied a little moisture and heat.


The Finished Result




Guild 302A Bass Guitar Broken Neck Repair

The Guild 302A , a unique vintage bass.

This Guild 302A bass was brought  into the workshop with a split in it’s headstock. This presented a fairly routine repair. It was to be a visible fix because of budgetary constraints.

During the course of the repair it was decided that the existing Badass bridge should be removed and an original BT-4 bridge be installed. The chances of finding a BT-4 were fairly remote and the original for this bass had been lost several years ago. However, with much internet searching and to the great surprise and delight of the owner a second hand BT-4 was located for sale in the U.S.

On receipt of the new BT-4, the Badass bridge was removed and the old style bridge installed. The frets were polished and fingerboard cleaned. All the electrical components were overhauled and cleaned. The bass was fitted with new Rotosound strings, the truss rod adjusted and the string spacing and intonation set.

What resulted was a unique vintage guitar restored to it’s former glory.

Apparently only 500 of these basses were ever produced.

Spec for B-302A

Manufactured: 1978-81

Body: Ash

Neck: Set 3-piece maple, with 20 fret rosewood fingerboard

Scale: 34 inch

Overall length: 46 1/4″

Width at nut: 1 5/8″

Electronics/pickups: Two Guild single coil bass pickups, two volume and two tone controls, selector switch

Hardware: BT-4 bridge