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August Issue
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Replacing the Soundboard on a 1977 Martin D-35

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Replacing the Soundboard on a 1977 Martin D-35


1. A close-up of the violated and damaged 1977 Martin D-35. 2. The anatomy of the original soundboard. 3. Martin’s replacement soundboard. 4. The original top’s finger braces. 5. The finger braces on Martin’s replacement top. 6. Inside view of Martin’s legendary craftsmanship. This ’77 D-35 is extremely clean.

This 1977 D-35 arrived at our shop with a big hole in its Sitka spruce soundboard and a bag of miscellaneous broken braces and slivers of spruce top wood. Of course, I was curious to know what had happened, but I was simply informed that someone had expressed themselves a little too much. The good news was the neck and fretboard showed no signs of damage, nor did the East Indian rosewood back and sides. Clearly this was a guitar worthy of being saved and not just laid to rest or parted out.

For those not familiar with the D-35 or the era it was built in, here’s some background: Martin introduced the D-35 in 1965 and it was the first Martin model with a three-piece back. This design reflected a shortage of Brazilian rosewood that was wide enough to make a two-piece, dreadnought- style back. In addition to the three-piece back, the D-35 included a bound fretboard and black-and-white purfling on the sides adjacent to the binding.

Martin had concerns about the three-piece back’s effect on tone, so as a part of their research, Martin luthiers made a few guitars using variations of the company’s different top and back braces. The builders concluded that using 00 top braces and 000 back braces worked best, and this resulted in the D-35 design we know and enjoy today.

The ’70s were tumultuous times for Frank Martin and the company, even though 1971 came with a record-breaking increase in production. The change from Brazilian to East Indian rosewood didn’t concern the buyers, as Martin’s sales weren’t slowing down. From the success of this boom, Frank Martin reached out and found other financial adventures to pursue, which for the most part never panned out. Towards the end of 1977, Martin employees who worked on the factory floor crafting the instruments went on strike. During this time, Martin’s office and management staff had to step up to those empty work benches and start building guitars.

With its history in mind, I carefully examined this D-35. There are times when an original soundboard can be restored—after warping, cracking, or receiving a mild blow, for example. In the vintage world, you want to preserve the instrument and keep everything original whenever possible. However, after diagnosing the damage, I concluded that the soundboard was too far gone and that the guitar would be much better off with a replacement top.

The first step was to remove the ebony bridge and soften the glue joint of the fretboard extension using Stewart McDonald’s bridge heater and fingerboard iron (item #4607 from stewmac.com). Then I removed the neck by applying steam into the dovetail joint while using the neck joint steamer (item #4059) to soften the glue in the pocket.

At this point, I traced out the top to give me a reference for replacing it later on. Then starting at the dovetail, I removed the top binding using a hair dryer and channel spatula. (Had the original binding not been damaged, I would have used a delicate procedure for removing the soundboard while leaving the binding attached to the rib.) Now with the binding off, I used a razorblade and chisel to separate the soundboard from the sides, while being careful to avoid splintering or loosening the kerfed lining.

I decided to use a replacement soundboard I’d purchased from Martin more than 10 years ago. Looking at the original ’77 top and its newer replacement, I noticed a few obvious differences. The original had the larger rosewood bridge plate that Martin implemented in 1969, whereas the replacement had a smaller but very stout maple bridge plate. The finger braces on the original soundboard are trimmed leaner, and I decided I’d shape the replacement top’s braces to be more like the original. I felt this would help the top respond better to the string vibrations, and not obstruct the glorious tone with a stiff soundboard.

Having taken a very close look at the exterior and interior of this D-35, I believe it exemplifies Martin’s legendary quality. Who knows? Maybe this was the last guitar to be built by the craftsmen in 1977 before they went on strike. Perhaps this was their final statement—a way of showing build quality as it ought to be.

Next month, we’ll discuss attaching the replacement soundboard to the Martin D-35 body.


John Brown is the inventor of the Fretted/Less bass. He owns and operates Brown’s Guitar Factory, a guitar manufacturing, repair, and restoration facility staffed by a team of talented luthiers. His guitar-tool and accessory designs are used by builders all over the world. Visit brownsguitarfactory.com or email John at info@brownsguitarfactory.com.
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