Carving the bridge.

I really enjoy creating the bridge because I get to work with beautiful dense woods and it allows me to be creative. A bridge is so important because it is the mechanism that transfers the vibrations of the strings to the entire top. When a string is excited (i.e., strummed or picked) on a fixed bridge instrument like this guitar,  it vibrates  lengthwise or “longitudinal” and so it pulls across the saddle and thus the bridge is rocked back and forth. This bridge movement transfers energy to the top causing it to vibrate. This vibration results in layers of compression and rarefaction that act like an air pump. The mass of the top makes the vibrations loud enough for us to hear!

The bridge must be strong enough to withstand constant rocking but it must not add undue mass to the top, thus damping the sound. I typically use Ebony but for Dan’s Ziricote guitar I am using a beautiful piece of Ziricote. First I take the block of Ziricote and sand it to a rectangle slightly larger than the final shape. I layout the saddle slot – it is compensated to the side that will accept the bass strings so it is about 1/8″ farther from the neck than the treble strings. I then locate where the holes will be for the bridge pins. I use a special proportional ruler to space the holes due to the differing thicknesses of the strings.

The bridge blank layout for the final shape, pin holes and saddle channel.

The bridge blank layout for the final shape, pin holes and saddle channel.

I will use a 13/64″ brad point drill bit in my drill press to drill the bridge holes.

Drilling the holes for the bridge pins.

Drilling the holes for the bridge pins.

I use a router and bridge jig to route the 3/32" saddle channel.

I use a router and bridge jig to route the 3/32″ saddle channel.

The next step is to use the band saw to cut out the shape. I then use a combination of belt sander, chisel, wood file, and sandpaper to contour the bridge. I bring the Ziricote to 800 grit sandpaper and it shimmers and looks awesome!

The finished bridge - extremely lightweight but very strong.

The finished bridge – extremely lightweight but very strong.

I then took a saddle blank made from natural bone and sanded it until it fit very snug in the slot. I made sure the entire bottom of the saddle rests evenly in the bottom of the slot to make sure all vibrations are transmitted to the bridge.

MDR-

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