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I'm very excited to be building my very own charango. For those of you who don't know, it's a 10 string ukulele sized instrument originating from the Andes mountains. They used to make them with an armadillo shell for the back, but the higher quality instruments are carved out of wood like a bowl. Traditionally the back and neck are carved out of a solid log, but I will be joining the neck to the body.

**I do have some questions as this is my first acoustic build. I need to know about bridge saddle height and neck bow. How do I set up the instrument with the most ideal action?**

Scale length is about 14.5", nut width is 2" Body is cherry, neck will be cherry laminated with 2 cocobolo strips. Fretboard and bridge will be osage orange. Top will be engelman spruce.

Here's some pictures of the body:


DSC_0021 by markpotato, on Flickr


DSC_0023 by markpotato, on Flickr


DSC_0024 by markpotato, on Flickr


DSC_0025 by markpotato, on Flickr

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http://www.tinyhouseandland.com

Surely you can find a suitable armadillo........

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Old growth, shmold growth!

Last week I found one dead and rotting in my old chicken house. Still had some ants on it, but the back was still in one piece, so give it another couple of weeks...

Seriously, this looks like an interesting instrument. Can't wait to see how that body looks once the carving is done, I've never seen one of those.

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Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

Thanks, hey maybe you could help me, I'm trying to find as much information as I can about setting this thing up with good action and string height. Do you think it would be necessary to compensate for neck bow by curving the fretboard plane? How do you set up a classical bridge instrument?

Anybody?

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http://www.tinyhouseandland.com

Direct string tie bridge like this? http://www.luthiersforum.com/forum/viewtopic.php?p=477595#p477595
That one has scale length 25", string-height-at-bridge of 5/16", and fingerboard tapering from about 1/8" at the soundhole to 1/4" thick at the nut... if I recall, I set the neck angle at pretty much zero (projection along neck without fingerboard is level with the soundboard at the bridge location). The action is nice and low... maybe even too low on the bass side, particularly at the upper frets. I'm still trying to grasp the ideal fingerboard geometry... you have to visualize the string going from the bridge to each fret, and make sure there's enough clearance on the frets past it, at the same time as achieving minimal action height all along the fingerboard when the string is open. It's easier when you have zero neck angle and a flat soundboard so the string-height-at-bridge and thickness tapering of the fingerboard are the only variables in question, but still not simple.

Oh, and it's an open debate whether a flat fret plane or a little bit of relief is better... I tend toward a little bit of relief, which I think allows having lower action at the high frets. But you still have to get the fingerboard thickness tapering just right.

What I did was cut the slots almost all the way through the fingerboard, add binding to cover them up, and glue it on thick. Then plane it some and string it up fretless to see how it looked, and repeat until I liked it. You can use a half toothpick as a movable fret to see how it will be once you add the height of the frets into the equation.

http://www.anzlf.com/viewtopic.php?f=1&t=3043

This is a thread on the ANZLF about just such a creature. Markus is also a very nice man and generous with his advice. I'm sure he'd be interested to see yours progress.....

My very first build was a charango - I was living in Santiago, Chile, and I went to a luthier who had several charangos hanging in his shop window because I was interested in buying one. He said "Do you want to buy one, or do you want to build one?" I didn't hesitate for even a moment.
I carved mine from a single walnut log. I still have scars on my hands from the blisters from the handsaw.

Awesome, thanks for the links and the stories guys, keep em coming!

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http://www.tinyhouseandland.com

When I worked in a stringed instrument sales/repair shop we would refer to this as a vegetarian churango. Have fun!

Funny. Not vegetarian though, bone nut and saddle for this one.

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http://www.tinyhouseandland.com

New question, bridge height relative to fretboard height (plus fret)? I've read that the normal string height at the saddle is 6mm to 7mm above the top. How tall (thick) then should the fretboard be, assuming the neck angle is flush with the top? Is a standard 1/4" board used? I figure since they use mm and not inches that this would not be the standard measurement.

Help?

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http://www.tinyhouseandland.com

Change of woods. Walnut neck and cocobolo fretboard now. I'm in a rush to get this thing done so the craftsmanship isn't what I consider ideal, but I hope to come out with an instrument that plays good.


DSC_0018 by markpotato, on Flickr


DSC_0020 by markpotato, on Flickr

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http://www.tinyhouseandland.com

More progress.


DSC_0020 (2) by markpotato, on Flickr


DSC_0021 (2) by markpotato, on Flickr


DSC_0022 by markpotato, on Flickr


DSC_0018 (2) by markpotato, on Flickr


DSC_0023 (2) by markpotato, on Flickr

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http://www.tinyhouseandland.com

Oh my, you had to hog all that out with a little 1/4" bit??!?!?

Aw, this is fun! Lookin' good. Keep those pics comin!

Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

Same way you carve an archtop. A bunch of tiny holes is more accurate than less bigger holes.

Lots of fun!

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http://www.tinyhouseandland.com

Mark, I will confess that I've never seen or heard one. Thanks for the lesson, can't wait to see the final product. You are a brave man.

Marty

Thank you. I've got the inside of the bowl pretty much done and the top plates are joined. The plate is long enough to get two tops which gives me a little insurance. Haven't decided on the rosette yet but I was thinking of gluing eight pieces of osage orange together in a circle.

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http://www.tinyhouseandland.com

This is awesome! Love it. Can't wait to see how it turns out.

Anyone have advice on bracing patterns? So far what I've seen looks similar to classical guitar fan bracing. This is my first acoustic instrument so I could use as many tips as you throw at me, even if they should seem obvious.

Thanks for the support guys! This forum is my biggest inspiration.

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http://www.tinyhouseandland.com

Question, when gluing the fretboard onto the neck, do you leave the area where it meets the soudboard unglued?

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http://www.tinyhouseandland.com

Are you going to be doing the style with two soundholes in the upper bout beside the fingerboard extension, or a round hole at the end of the fingerboard like a guitar/ukulele?

If the former, then just one cross brace under the end of the fingerboard extension would probably do it, considering the bowl is so strong by itself (assuming you left it pretty thick). If the latter, then two cross braces, above and below the soundhole.

For the bridge area, fan bracing should be good... maybe 3 fans. Or go fanless like on that coral snake guitar I linked before. With the low string-height-at-bridge, there's not too much danger of running into structural issues from bridge torque. What's the total string tension? Somewhere around 100lbs? And lower bout width, and distance from tail to the nearest cross brace. Those will determine your necessary top stiffness... although it's still subject to the particular piece of wood. But I'd estimate somewhere around 2mm would be good for engelmann.

And do glue the fingerboard extension down. If you left it hanging it might rattle, or at least not be as solid of a backing for the strings at the upper frets. Plus it helps a little bit in resisting neck torque. Also, with an effectively integral neck like that, you'll never be ungluing just the extension anyway.

Thank you. Its a round soundhole. Don't have the other specs on me though. Thanks for the info.

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http://www.tinyhouseandland.com

Here we are:

Upper bout: 5 1/8"
Lower bout: 6 3/4"
Waist: 4"
Soundhole diameter: 2 1/4"

And some fresh pics:


DSC_0001 by markpotato, on Flickr


DSC_0002 by markpotato, on Flickr


DSC_0003 by markpotato, on Flickr

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http://www.tinyhouseandland.com

I wonder if it's thick enough to carve an armadillo shell pattern into the back?

You can maybe even make a wooden armadillo head to glue on.

These things just don't look right to me without being armadillos.

I guess it's just a hang up of mine.

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Old growth, shmold growth!