1. A 1971 Gibson SB 300 bass with embossed script logo
single-coil pickups. 2. Hurray! All original solder joints
and components. 3. The bridge cover with Gibson’s nostalgic
script logo. 4. The original nylon saddles have collapsed
on this Multiplex adjustable bridge.
Recently, a client brought in a cool 1971
Gibson SB 300 for me to inspect and
prepare for sale. The SB 300 is a double-cutaway
bass with a nitrocellulose-finished
alder body, a set 3-piece maple neck, and
30.5"-scale rosewood fretboard. As I played
this short-scale bass acoustically, I was
treated to a very clear, even tone with no
dead spots or resonating hot spots. When
it comes to bass construction, you just can’t
go wrong with this combination of alder,
maple, and rosewood.
The SB 300 was Gibson’s first bass to
have single-coil pickups, and it sounds
great amplified, too. The controls are
simple—a master volume, tone control,
and an on/off slider switch for each script-embossed
pickup.
Peering under the metal control plate,
I was delighted to see all-original solder
joints. The Centralab 250k volume and
tone pots had a code of 1346607, which
indicated they were manufactured in 1966.
Fortunately, no one had pirated these parts
for a ’66 restoration. Checking the electronics,
I found everything to be in excellent
working order.
The problem lay in the Multiplex
adjustable bridge. The unit itself is made
of metal, but the original saddles are
made of nylon 6-6, a material used in
bearings and gears due to its abrasion
resistance and self-lubricating properties.
Though nylon 6-6 can be successfully
used in many applications, bass saddles
isn’t one of them—at least over the long
term. On this bass, the saddles had collapsed
from supporting medium-gauge
strings for years.
After removing the collapsed saddles
from their intonation screws, I was able to
construct a model of the original saddle
from various broken saddle pieces. This
was a crucial first step in finding replacement
saddles.
5. Comparing
a reconstructed nylon saddle (left) to the Graph Tech Tusq
replacement. To make it fit in the Gibson bridge, I’ll need
to remove a little material from below the new saddle’s
“shoulders.” 6. Shaping the replacement Tusq saddle.
7. Slotting the low-E saddle with a .105” nut-slotting file.
Examining the reconstructed saddle, I
realized that with some fabrication I could
use traditional Nashville Tune-o-matic
metal saddles. I was reluctant to do this,
however, because I wanted to stay as close
as possible to the original design. At the
same time, I really didn’t want to craft
new saddles from nylon material. I had to
assume this bass was going to be played
hard, and I wanted it to be completely
roadworthy after leaving our shop.
After weighing our options, the owner
and I decided to go with Graph Tech
Tusq saddles. Billed as “man-made ivory,”
Tusq is a synthetic material with both the
strength and visual appearance we were
looking for. I selected Graph Tech’s #8501-
00 model, which is a replacement for the
post-2000 Gibson Nashville Tune-o-matic
bridge saddles. With a little modification,
these saddles would fit in the SB 300’s
Multiplex bridge.
Gripping each saddle in a nut and
saddle vise (item #1816 from stewmac.
com), I trimmed away the required material
with nut and saddle-shaping files
(item #4556). With some careful work,
the modified saddles perfectly fit the vintage
Gibson bridge. The last step was to
use gauged nut-slotting files (#5313) to
cut string slots that were sized to securely
hold each string and match the fretboard
radius. With that done, this bass was
ready to provide many more years of
toneful service.
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.