TAKE ONE EIGHT=STRING FRETLESS ACOUSTIC GUITAR
CUT A BLOODY GREAT HOLE IN IT...
I used a hand router with a circle cutting attachment, after first drilling a guide hole.
Notice that this cuts through the bracing and compromises the strength of the top.
Carefully remove the sensor for the piezzo pickup. Make sure during all that cutting you don't cut through the wiring or you're going to have to mend it. (Not the end of the world.)
CUT TWO SMALLER HOLES.
This time a circle cutter can be used, but remember to clamp two small pieces of wood behind the table, or the circle cutter will tear away the back of the wood.
Now we have to think of reinforcing the top. Here's what we have so far. Notice the sensor hanging loose.
GLUE IN ADDITIONAL SUPPORTS FOR THE TOP.
You can also glue in the small hole covers.
MASK THE FINGERBOARD. CALCULATE THE FRET POSITIONS USING AN EXCEL SPREADSHEET. MARK THE FRETS ON THE FINGERBOARD.
Note that in order to calculate the fret positions it is useful to cover the hole with cardboard and mark on the position of the bridge and the center line. Calculate the fret positions in MILLIMETRES, However much you might like to work in inches the calculation will give fractions of an inch, and very few rulers are marked off in hundreths of an inch !
CUT THE FRET POSITIONS WITH AN XACTO KNIFE. (TWO CUTS PER FRET.) REMOVE THE STRIPS OF MASKING TAPE WHERE THE FRETS ARE. PAINT OVER THE GAPS WITH GOLD PAINT, (which matches the resonator... use any color you want.)
REMOVE THE MASKING TAPE. CHANGE THE TUNERS FOR GIBSON-TYPE WHICH MATCH THE RESONATOR.
BUILD A NUT
The base is carved ebony. I like to use threaded steel rod for the nut. This allows you to change the string spacing any time you want, and it keeps the strings in position securely.
SCREW DOWN THE RESONATOR PLATE AND CONE.
Notice the additional two holes cut into the tailpiece. I've seen people put eight strings into six holes but it's not very secure. Eight-string tailpieces are available if you want to spend more money.
What you can't see here is the bridge. The spider has a slot. I rounded out this slot with a file to the same diameter as the tapped rod, and used the same tap rod as on the nut, remembering to leave a space at the centre so that the cone can be adjusted if necessary. In other words the bridge is two short pieces of rod, glued in with impact adhesive.
It is not commonly known, but the piezzo pickup sensor does not have to be underneath the bridge. I glued it direct to the spider, just in front of the bridge.
AND THERE WE HAVE IT... AN EIGHT-STRING ACOUSTIC/ELECTRIC RESONATOR GUITAR.
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Houlàlà; huit cordes sans neck-stick...à l'heure qu'il est elle doit ètre un peu tordue.....