Guizouki - Tanglewood Nashville
Converting a Tanglewood Nashville folk guitar into an eight-string guizouki
The original guitar
This conversion was based on a second-hand Tanglewood Nashville folk guitar.
They are designed in the classic traditional western style, combining premium solid Himalayan Spruce top, African Mahogany back and sides with Rosewood fingerboard and bridge.
I'd been looking for a while and chose this because of the quality of the construction and the narrow neck.
I started by making a one-to-one scale drawing on my computer to work out the dimensions of the tuning holes, nut and bridge.
The headstock
1. Planning the headstock
As with the Fender Squier, the first task was to adapt the headstock to take eight strings - four pairs.
With this conversion I wanted to retain the Tanglewood decal with a darker veneer on the outside.
2. Plugging and veneering
Having plugged the top four tuner holes with dowel, I clamped some scrap wood onto the headstock to protect the middle section and sanded the dark veneer away to a depth of about 3mm.
I cut two pieces of mahogany veneer slightly larger than the side sections of the headstock and glued them on.
3. Preparing the tuner holes
After 24 hours, I took off the clamps and sanded the veneer to fit the contours of the headstock.
As with the Squier conversion, I had made a one-to-one scale drawing on my computer based on the guitar and the tuners I had bought online.
I used a printout of the headstock to create a template to locate the tuner holes and drilled small guide holes.
4. Drilling and fitting the tuners
Using the small guide holes, I drilled the tuner holes in the headstock.
I am lucky to have a neighbour with a bench drill who helped me to ensure the holes were vertical to the headstock; otherwise I would have used a jig to guide my hand drill as I did with the bridge.
After a few coats of varnish I fitted the tuners.
5. Making the nut
The nut is made from bone sanded and filed down to the dimensions shown in the diagram.
There are several good tutorials on YouTube showing how to shape and file a nut to get an optimum playing action.
The best advice I can offer is to take your time. Lower the action in small stages, retuning in between, until you get a good action.
The bridge
1. Plugging the original holes
The rosewood bridge of the guitar has six pin holes. I needed to drill two rows of four holes while retaining the rosewood look.
I used beech dowels to plug the holes and rosewood plugs to cover the dowels.
2. Marking the new pin holes
I used a template made from a printout from my one-to-one scale drawing to locate the pin holes and drill small guide holes.
The spacings, shown in the diagram, are based on online research and those I used for the Squier conversion.
3. Drilling the bridge
I made a drilling jig to ensure that the holes would be vertical to the bridge.
I used two drill bits, one for the pin hole and a slightly larger one to make the seat for the pins.
The picture shows the drilled bridge with the rosewood plugs visible. I have subsequently treated the bridge with lemon oil so that they blend in.
4. Making the saddle
The saddle is made from a bone blank filed and sanded to the dimensions shown in the diagram below.
I decided to make a compensated saddle based on online research and some trial and error.
The finished guizouki
The guizouki is currently strung with a set of Clifford Essex Octave Mandola strings, in pairs with the following gauges:
.044", .030", .020", .012"
It's tuned to G D A E.
The A strings are wound, rather than plain wire, to give a richer sound.
When I next restring, I'll probably buy individual guitar strings of the same gauges.
