’58 Gibson J45

Fletcher has presented me with a New Year Project- an absolutely pristine 1958 model Gibson J45 Adj Bridge…perfect except for this…

…a very nasty split in the 50 plus year-old top.

It would seem that as these old guitars age, they dry out over the years and if you’re unlucky, a split will appear pretty much where this guitar has split- alongside the neck, and perhaps also along the edge of the scratchplate.

My first thought was that it might be possible to carefully clamp the split closed, but no, that wasn’t to be.

In this case, the split has grown to a couple of millimeters.

So what has to happen for the top to become integral again is to splice in a new piece of spruce to match up with the sitka spruce top.

Now Fletcher tells me that removing the scratchplate is undesirable as well as tricky, if not impossible.

But because I have to splice in a new piece of wood and then disguise the repair, I’m not left much option but to remove the bridge AND the scratchplate.

So here goes…

This is my setup to gently supply sufficient heat to allow removal of the bridge.

Years ago, in a previous life, I used to teach in a secondary school where I taught woodwork, farm plumbing and music. And a touch of ag. science. Which is how I acquired the retort stand pictured, over 40 years ago. Just the thing for holding the heat gun which I’ve used for a least 20 years to do exactly what I’m doing now. The best way to make sure that I don’t apply too much heat is demonstrated here…

So starting at a corner, the bridge is very carefully removed.

Now, removal of the scratchplate employs a similar technique but because I suspect the scratchplate is acetate, I’m going proceed very carefully. Too much heat and – spontaneous combustion! And we don’t want that…

Anyway, the scratchplate is gently lifted at a corner and a large spatula with no sharp edges is used to gently lift off the scratchplate, fortunately with no drama whatsoever.

Now the split can be studied more clearly before moving to the next step.

Fortunately, the rosette hasn’t split at the site of the crack because that would have added to the complexity of the repair. And it can be seen that the split doesn’t just follow a straight line.

The splits have to be reinforced and the top either side of the split realigned before anything else happens and appropriate pieces of spruce of the same thickness as the top are glued in, under the larger split along the scratchplate.

This photo is taken through the soundhole using my inspection mirror and shows the patch, or cleat, glued in between the X braces on the treble side.

The split runs from the soundhole to the inside of the saddle adjustment insert, where the bridge plate- that’s it with the saddle insert’s brass nut on it- has stopped the crack under the bridge.

A piece of  spruce is also glued in under the top at the neck, under the fretboard extension.

The trickiest aspect of this repair is going to be to minimise the appearance of the crack and that shouldn’t be too difficult where the sunburst is at its darkest.

Behind the soundhole will be different, though…

Now to simplify the repair, the split is – well- simplified by gluing where the split separates and wedging the second split using a spatula while the glue dries.

And while it’s drying, I can simply fill the sound hole crack using black filler.

Now that the split has been made easier to repair, I’ll hunt through my bits of spruce that I’ve collected over the years to find a suitable piece that I can cut a sliver from.

The piece on the right should be good and I’ve cut a sliver of spruce that can be tapered to be a neat fit into the crack.

A test fit indicates that all should be good…

…and it’s glued in…

…and clamped while I go and check the cricket score.

The glue has dried and another piece is inserted in the crack at the sound hole.

Now the spliced-in piece can be trimmed flush with a very sharp chisel…

…and then cleaned up using very fine sandpaper.

The touching-up technique involves shellac, an appropriate coloured wood dye and a very fine paintbrush…

…and a steady hand.

The technique is to continue to paint more of the stain/shellac on the splint until the appropriate colour is achieved.

Trying the scratchplate back in its original position lets me see how I’m going.

Not too far off…

When the colour is as near as I’m going to get, I’ll go over the repaired areas with nitrocellulose lacquer on the same tiny paint brush so that I can polish over the repair when it’s dried.

In the meantime, the Brazilian rosewood bridge has a split that needs to be repaired.

This also seems to be a common occurrence with these old guitars. The saddle leans forwards over the years and as this is the weakest point on the bridge, a split occurs. For the time being, though, this is all that needs to be done.

While the bridge repair dries, I’ll sort out the scratchplate. Rather than the acetate cement that was used originally, I’ll use the more modern technique of using double sided adhesive film. Using this method also insures that in 50 years’ time, the guitar won’t develop another split…

I’m scraping off the remains of the old cement…

…and applying the adhesive film before carefully replacing the scratchplate in its original position.

Now is the time to refit the bridge and clamp it back in its original position.

After a suitable time, the clamps are removed and the saddle re-installed. Here’s something else unique about these old J45s- a ceramic saddle…

Except for stringing up, this repair job is done.

The top is again all one piece and the site of the repair has been-as much as possible- been disguised. In keeping with the guitar’s really original condition, the frets just needed a bit of a clean up and fret wear is really only minimal.

I’m really looking forward to hearing just what a 1958 Gibson J45 “Adj Bridge” acoustic sounds like.

If it sounds as good as it looks….