Cavaquinho construction-the final steps

October 1, 2011

Now that the lacquer is buffed to a high shine I can get ready to string up the instrument.

First, the tape is removed from the fretboard and the spot on the soundboard where the bridge will be glued.   Any little bits of lacquer than managed to seep under the fretboard tape are scraped away.  I double check the location of the bridge to assure that the strings are properly aligned with the edges of the neck, and that the bridge location allows the proper amount of compensation for the string length.  As one plays higher up the neck, fretted instruments tend to start sounding sharp.  By moving the location of the bridge a little farther back from its calculated spot–which would be exactly twice the distance from the nut to the 12th fret–one can “compensate” for this tendency for the intonation to go sharp.  In the case of the cavaquinho, I have found that locating the bridge about 3 mm back from its theoretical spot provides the best intonation.  I did not take any pictures of the bridge gluing process, but it was glued to the soundboard with yellow aliphatic resin and held in place with a couple of clamps until dry.

After gluing the bridge, I make the nut and saddle from pieces of ox bone.  I prefer bone nuts and saddles on most of my instruments.  Each type of material, whether it is bone, various types of synthetics, or even ivory, has a characteristic influence on the tone of the instrument.  I prefer the tone of bone, and it is also more durable than plastic.   These pieces are critical to how the instrument will play.  The slots in the nut have to be cut to just the right depth to allow minimal finger pressure to play the notes at the first few frets, yet not so deep that there is any buzzing on the first fret when an open string is played.  Also, all of the slots must be carefully filed to leave the strings at the same height.   Here is a picture of the roughly cut nut being sanded to the same radius as the fingerboard:

After the nut is shaped, I mark the locations where the slots will be and carefully file them.

The saddle is cut from another piece of bone.  It is sanded to the proper thickness to fit in the bridge slot,  then its top surface is reduced to the proper height to allow the strings to be roughly 1/8″ to 3/32″ from the top of the 12th fret.  The strings are a bit higher on the bass side than the treble because the heavier bass strings vibrate more freely, so they need to be higher to keep from buzzing on the frets.   This picture shows how the finished saddle is sloped in such a way as to allow the treble strings to be closer to the fretboard. 

Now the tuning machines are installed.  I prefer to use geared tuners on cavaquinhos because they are more durable and easier to adjust than friction pegs, but I have seen some cavaquinhos with friction pegs.

Finally the strings are installed.  After letting the instrument sit with the strings tuned to pitch for a few days, I make the final adjustments to string height at the nut and saddle and the cavaquinho is finished! 

Here are a few pictures of the finished project.  I hope you have enjoyed reading about it.

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3 Responses to “Cavaquinho construction-the final steps”

  1. Baptiste said

    Hello,
    It is a very nice work.
    I am thinking of making one my self.
    A friend told me the shape look like a OM in smaller size.
    What do you think of the use of an heavier wood instead of spruce for the top ?
    do you know where I can get some drawings ?
    thanks for your blog anyway as it’s a source of inspiration !

    Baptiste

    • I have used koa successfully on the top. Mahogany would probably work alright, but denser wood would probably reduce the tone and resonance of the instrument.
      I do not know of any drawings. I built my first cavaquinho after studying and measuring a DelVecchio cavaquinho from Brazil.
      I am glad you enjoyed the blog.

      • Baptiste said

        Alright ! thank you for your quick answer !
        I don’t think there is any drawings anywhere !
        It will be more fun to draw my lines anyway.

        I think I’m gonna compare few species that I can find easily in my area (in France). I’ve got some really awesome french walnut, with beautiful colors.. but it must be heavier than Koa.
        it’s a shame as my father live in Brasilia and he ordered me a classical guitare, the cavaquinho is a surprise… so I can not ask him to look for precisions ! 🙂

        it’s very kind of you to take the time to write all of this !
        Greetings !

        Baptiste

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