Years ago, a local public school asked me to repair a bass (Cheap Chinese, as I recall, but it has been a while). The Fingerboard had come unglued, and, rather than de-tensioning, and calling a luthier, they had simply bound the board to the neck with cellophane tape (Yep...scotch-tape) and kept playing it. There was about an inch of clearance under the strings, and it was still up to tension...somewhat.
I had never heard of CF reinforcement at the time, so that was not on the horizon. So, I scraped both the board and neck clean, then used a nylon rope and some padded blocks to flex the head/neck back until the neck surface was flat, when checked with a straight-edge, and re-fitted the same board, without alterations. I slathered on the hot hide glue, clamped carefully and thoroughly, and when all was complete, and the intrument was tuned and playing, the neck was as straight as it had been when new, at least. There was no "excess material" to remove, and very little labor involved. Pretty simple fix, and everyone was happy. No idea how the sound compared before and after.
A few years later, an old Kay came to me, whose original rosewood board was too thin, having been dressed many times, and the neck was badly broken. The owner wanted the neck replaced, and wanted the old neck and fingerboard for wall-art. OK... it had some old bolts and dowels and stuff that I had to remove, but I ordered the new neck, and a new ebony board (Rosewood was not available), and commenced the job. Right away I found out that the original dovetail neck and the new one were not the same shape at all, and the new neck was just about as flimsy as the old one. I had to modify the neck to make the heel fit, and re-carved the scroll to match the old one, but it still was flimsy.
I called the customer and recommended the carbon fiber reinforcement. He approved, so I cut two slots radiating from center at about 60 degrees, and installed two thin, flat bars, embedded in epoxy, all around. While the epoxy set, I back-flexed the neck a tiny bit, so that I could plane it dead-flat afterward. The rods were well below the surface, and it did not occur to me to cap them with wood. That would have been a good idea. The CF came from the Dragonplate company...
When all was complete, the new neck matched the old body, and the whole bass looked good. The player was pleased with the sound, so it was successful. The thicker ebony board made the bass more comfortable to play, and the rods added stiffness without adding much mass. (It was my first experience with CF, and I was continually attempting to flex them in my hands, and amazed at how stiff and light they were.) I set up the instrument with the string height at the nut lower than the player had ever had, and he was thrilled with how easy it was to play. Overall it was a stressful, but good experience. Again, everyone was happy.
Too small a sample to be meaningful, I know, but it seems to echo the experience of those luthiers with hundreds of times the experience, and perhaps gives some information as to what is involved with installation.
I had never heard of CF reinforcement at the time, so that was not on the horizon. So, I scraped both the board and neck clean, then used a nylon rope and some padded blocks to flex the head/neck back until the neck surface was flat, when checked with a straight-edge, and re-fitted the same board, without alterations. I slathered on the hot hide glue, clamped carefully and thoroughly, and when all was complete, and the intrument was tuned and playing, the neck was as straight as it had been when new, at least. There was no "excess material" to remove, and very little labor involved. Pretty simple fix, and everyone was happy. No idea how the sound compared before and after.
A few years later, an old Kay came to me, whose original rosewood board was too thin, having been dressed many times, and the neck was badly broken. The owner wanted the neck replaced, and wanted the old neck and fingerboard for wall-art. OK... it had some old bolts and dowels and stuff that I had to remove, but I ordered the new neck, and a new ebony board (Rosewood was not available), and commenced the job. Right away I found out that the original dovetail neck and the new one were not the same shape at all, and the new neck was just about as flimsy as the old one. I had to modify the neck to make the heel fit, and re-carved the scroll to match the old one, but it still was flimsy.
I called the customer and recommended the carbon fiber reinforcement. He approved, so I cut two slots radiating from center at about 60 degrees, and installed two thin, flat bars, embedded in epoxy, all around. While the epoxy set, I back-flexed the neck a tiny bit, so that I could plane it dead-flat afterward. The rods were well below the surface, and it did not occur to me to cap them with wood. That would have been a good idea. The CF came from the Dragonplate company...
When all was complete, the new neck matched the old body, and the whole bass looked good. The player was pleased with the sound, so it was successful. The thicker ebony board made the bass more comfortable to play, and the rods added stiffness without adding much mass. (It was my first experience with CF, and I was continually attempting to flex them in my hands, and amazed at how stiff and light they were.) I set up the instrument with the string height at the nut lower than the player had ever had, and he was thrilled with how easy it was to play. Overall it was a stressful, but good experience. Again, everyone was happy.
Too small a sample to be meaningful, I know, but it seems to echo the experience of those luthiers with hundreds of times the experience, and perhaps gives some information as to what is involved with installation.
