Acoustic guitar restoration

1942 Martin 000 28



Martin 000 28 (1942) is a truly rare instrument.

A legendary model in the history of guitar making, built in the “golden era” of Martin guitars. It is very different from the modern equivalent model although externally they look identical. The rare materials that are no longer used (Adirondack spruce, Brazilian rosewood) and lightweight construction without a truss rod, are some of the facts that make this instrument unique.Unfortunately the guitar was not in a good state when we received it. It needed tons of restoration work in order to regain its former glory but it was really worth the effort.


The following video presents images and a recording of the guitar after the restoration. The recording took place in a dry sounding room without the use of reverb or any other effect. The sound was absolutely stunning. Many thanks to Giannis Kousis for playing the guitar in this recording.












> The peghead: In this model, the original peghead was solid as the tuners fitted on the back of the peghead. At some point the original tuners were replaced. Perhaps because of the difficulty to find the appropriate solid head tuners, the peghead had been slotted in order to fit side tuners.
>The bridge: The original bridge had been replaced with another one. This replacement had also been fitted with two huge wooden dowels.
>Neck & Fingerboard: the neck was loose. The fingerboard was broken vertically and had been mounted with nails.
At the first fret the neck was so worn down that the two strings on either side where practically in the air!
The fretboard has been badly chipped due to bad fret work.
The perl position markers are missing or broken.
>The soundboard: The main problem with the soundboard is caused by the celluloid pick guard.
Because it has shrunk, it has pulled the wood and as a result the soundboard broke and sunk at the pick guard area. There is no doubt that the interior of the guitar will be effected by this problem.
The sound hole is worn and some of the decorative veneer is missing.
>Guitar interior: In order to get a good look of the guitars interior i used a micro camera. Indeed, the brace under the shrunken pick guard is ripped in half. Unfortunately at some point the brace had been glued and thereby "locked" the soundboard in a deformed shape.
The wooden dowels used to glue the bridge.
Various repairs had taken place using a white glue of unknown origin.
The interior bridge plate is very worn down.
The all braces of the back are loose.
>Varius: The back has small cracks to be repaired. Also the original nitro lacquer has been scraped and another lacquer has been applied with a brush.
Parts of the celluloid perflings are missing...
...or have been replaced with wooden ones.
>Fingerboard & neck removal: First the frets must be removed.
Once the frets have been removed, I slightly heat the fretboard and start ungluing it from the sound hole end.
The nails...
...and the vertical breakage.
The neck was practically held in place by the fingerboard and was easily removed.
First I'm going to repair the worn down edges of the fingerboard at the first fret.
I chisel down the ebony until it is flat.
Then glue some ebony to replace what is missing on each side.
Plane excess wood.
Now to the lower part of the fingerboard. First I glue the cracks with cyanoacrylate glue.
In order to reinforce the vertical breakage I must do some routing underneath the fingerboard and glue inn a thin strip of ebony. This way it will become strong as new.
The routed fingerboard and strip to be glued.
I glue it in place.
When the glue dries, I plane it and it's ready.
Preparing the neck before gluing the fretboard.
I prepare the hide glue. The right temperature is very important to the quality of the joint.
I quickly glue the fingerboard before the glue gels.
Once it's been glued, I will fill the ebony chips that are missing with glue and ebony dust.
The missing abalone position markers are replaced. They are exact copies and hand cut just like the originals.
I lightly sand the fingerboard.
...good as new. The frets will be placed latter on.
>The peghead: First I remove the rosewood that's been added to the rear side.
I will add mahogany parts to fill the holes. First I start with preparing the parts.
Additional parts have a wedging shape and thus the repair will be very strong.
Now I prepare the peghead. First I must remove the sides.
This head has seen better days...
Adjusting the peghead so the new pieces will be glued to have a perfect fit.
when everything fits perfectly...
...I glue them.
After planing excess parts, the sides will be cut off in order to add extra parts of wood.
Cutting the side additions to the correct shape.
Two mahogany bits will be glued to make the repair even more durable and also to cover the holes making the repair invisible from the side.
... and glue together.
Planing and shaping the final outline.
I will now cover the addition on the front of the peghead with a thin piece of rosewood. Fortunately I found a piece that fits perfectly with the central part.
I carefully carve around the logo.
...preparing the rosewood parts.
It takes time, but with a bit of patience I found the perfect match.
Gluing it together...
It all went well.
The back of the peghead will be covered with a thin piece of mahogany, this way the repair work will be totally invisible after being lacquered.
Gluing the thin pice of mahogany.
After the lacquer the repair will be invisible.
Drilling holes for the tuners and the peghead is ready.
>The body: It is time for the body. First I must remove the bridge. I start by removing the wooden dowels.
Then I will plane the bridge in order to remove it easier once it has been heated slightly.
I place a heated piece of iron and as soon as the glue is soft...
...I remove it carefully.
It was removed successfully without pulling wood fibers from the spruce top. Once removed, you could see the damaged area where the original bridge had been removed and its boundaries. You could clearly see that the pin holes had been filled and reopened a couple of times.
Now its time for the pick guard. I apply some heat in order to remove it with ease.
Removing it carefully.
I will now unglue the back in order to proceed with the interior repairs. First I will remove the purflings with much care.
The purflings will be stored and re-positioned later.
I take the back off.
Once the back has been removed there is easy access in order to start the repairing.
Starting from the back. Firstly I'm going to clean off 80 years of dirt build-up.
The loose brace edges will be glued.
Also cracks are glued with reinforcements.
Now I start on the soundboard interior. After the brace split and the sounboard sunk, the brace had been carelessly glued and as a result the soundboard had "locked" in a deformed shape. Now, the brace has to be removed in order to straighten the soundboard and then re-glued.
All the braces within the deformed area will be removed.
Removing old glue from the brace.
I tightly clamp a heated flat piece of iron to the deformed area and leave it this way all night long to straighten.
Now I will repair maple bridge plate. Bridge plate is a flat piece of wood that reinforces the soundboard on the inner side of the bridge position and holds the strings. The pin holes have been filled and re-opened more than once. As a result of this the holes have lost their shape.
With a special tool I make hemispherical maple caps to close the holes from the inside and spruce caps for external.
I now prepare the holes with the counterpart tool in order to glue the caps...
...then glue.
On top of the interior caps I will glue a thin piece of maple wood that will reinforce this repair.
I continue with the exterior of the soundboard in the same way.
The sounboard is now ready for fresh new holes.
Removing the white glue from previous repairs and repair from scratch cracks and fractures.
Now the broken brace will be glued with the help of a special plastic. This material softens in hot water and then you can give it any shape you like. When it cools down it hardens like rock.
Gluing the brace with the use of this customized plastic "clamp" I made.
Now it is glued in the right position.
Reinforcements are made in the are damaged area...
... strong as new.
A bit of touch-up on the repairs that may show when the guitar is ready.
Now a thin piece of spruce will be glued internally round the soundhole. This will straighten the deformed area and also will give us α bit more surface in order to build the missing rosette parts.
The guitar interior is finally ready.
The soundboard is back to its original shape.
It is time for the rosette. Fist I remove the damaged wood.
Next I will make with the router a piece that will fill the gap.
I glue it in place.
I place the missing plastic purflings.
With scraper ι remove the excess material.
A touch-up and its ready.
Time has come for the back to be put in place again.
Now the neck will be fitted. I remove the dry glue and make the necessary adjustments in order to be perfectly centered and have proper action when the strings are on.
Now I have to wait...
>Detail adjustments: Once the guitar has been varnished with nitro lacquer, it is time for the final adjustments and the setup. The bridge will be glued in place.
Once glued, open holes and shape them with reamer so as to achieve a perfect fit with the pins.
The tuners chosen are the type that Martin traditionally uses. To our good luck I found a relic version that where perfectly suited to the age of the instrument.
Fitting the tuners.
Making the bone nut.
A bit of line seed oil to finish the fretboard.
I put the strings and for the final touch...glue the new pickguard made of a similar material that Martin used in 1942.
Ready. Not bad 80 year old!