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Thinking about the Roundtable coming up. I don't really think about thicknessing wood. I have bunch I just had sanded down to 1/8", mainly to get it flat. It is still too thick. I have this little Voboam baroque to make into a 8 string uke in A. I had to replace the Englemann top that was splitting all over. Does that happen to everyone?

The old one easily flexes a LOT at 2mm thick. This one doesn't. It is fairly flexible cross grain; but not really much. NOTHING like the flex that I saw Marshall Brune getting on the tops and backs that he said were still stiff! Taking it into the computer room to check the tap tones on Audacity, because they don't seem too bad, and I saw it in the sunlight coming through the front window.

Ahh. I see.

The bear claw, and strong growth lines really stiffen the top. Really stiffen it. Here it is on my Lightbox.



Another thing to think about is that the stock it 13" long, but it only has about 9" between the blocks! It is 6" wide.



Tapping it in Audacity I got 5 notes at about the same level and one that was the ring tone above them.

91 F#2
108 A2
134 C3
166 E3 the ring tone
210 G# 3
234 A# 3

There were other overtones, but just a gradual decline, no real peaks.

You also have to think about what the character of the instrument is. It seems like it is more of a percussive instrument. Is that correct? I know that the Baroque guitars are like that, they even tap on them like flamenco guitars. Quick response, rapid decay.

Also the bracing of the guitar. This one has 2 full cross braces. It has 1 that doesn't go all the way across. I've never seen one like that. Then it has 2 that seem to be there to help keep the bridge from ripping off!

Most of the movement is in a 5" oval. So maybe that area has to move, and it is constrained by the bridge, and the diagonal braces?

Anyway, I thought it was interesting.

I think I'll cut it 1/4" or so big all the way around, and see how it feels then. It seems like the bass side will lose a lot of stiffness.

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Why be normal?

"Bear claw" (Hazel fichte) wood is supposed to have superior qualities for instrument making. Engelmann spruce can vary a lot in its properties. I don't think it is as tough as Sitka, but I haven't noticed it being overly "splitty", at least compared to WRC or redwood. The denser Engelmann with the dark grain lines I do find to be stiffer than the paper white stuff sold as the "better" grade.
The Voboam guitar looks like a neat little instrument. What are the approximate dimensions? What made you decide to go with 8 strings instead of 10 (or 4)? The bridge being near the bottom of the body (lute like) allows for a longer scale length on a shorter instrument. Are you tuning it as a baritone uke?

2mm would be awful thin for my work but I am not building anything nearly this small so my experience is probably of no use. Anyway Ken, you have a unique approach to building and I enjoy following along, thanks for posting.

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Steve Smith
"Music is what feelings sound like"

Clay, I have seen and used Englemann from .29 - .44 sg. It does seems softer to me. The heavier stuff is pretty good. A very light one made an easy to play violin, but though it sound fine, I don't think it has any sort of "extra" to it.

The guitar is one that never was. It is from this:



It is included as a stand alone instrument in the complete set of Voboam plans made up by the Dutch Luthier https://thedutchluthier.wordpress.com/b ... ent-plans/ His plans are very good. That set has everything you need to make probably 250 different degrees of bling on a baroque guitar. He has the free Vihuela plan too; I have that started as well. That one is very simple, except the rosette.
https://thedutchluthier.wordpress.com/2 ... ela-plans/

This one is about a 10.5 X 6 inch body. He suggested making a 4 course, but gave it a shorter neck, I don't know why. I left it with a 442mm or so scale. I think that is about what a tenor ukulele is.

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Why be normal?

Hi Ken,
That is a tiny guitar! You are right - the scale length would be about what a tenor uke uses.
An odd coincidence happened a couple of weeks ago. I started building a dulcimer for a friend of mine, and as I often do, I tried to figure out what I could do with the off fall from the soundboard material. I started playing around with the template I use for concert uke sides, but making it narrower to fit the scrap material. This is what I came up with - it is about 12 inches long and 7wide (lower bout)

There you go Clay. It should work just fine.

I was just thinking about bridge placement on the Voboam, and the one you drew up. The bridge is very low on the Voboam, but it would be higher on yours. The character of the sound would probably, or at least could be much different. The bridge on both should be near the widest part of the bout. The Voboam would probably have a punchier? sound.

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Why be normal?

Hi Ken,
I have used a tenor scale on a concert body and it does push the bridge down some, but not as much as you might think. I built a uke for my brother with a concert size body and a 16 3/4 inch scale and the bridge position looks pretty normal. After him sitting on it twice and me repairing the top twice he asked me to make a case for it. The down side to non standard dimensions is finding a commercial case that it will fit. I've made a few "coffin" cases for guitars, but this one looks even more like a baby's coffin.

As to how the Voboam might sound, I don't know. I think the soundboards are treated somewhat like lute bellies with the bridge located low down and the bars overlapping the bridge used to tune the response of the guitar. The late Robert Lundberg in his lute making book goes into this some for lutes, but that might also apply to the guitars with similar bridge locations. I wouldn't be surprised if the guitar didn't sound somewhat like a lute.

This looks like an interesting blog to peruse a bit. At the bottom of the page you can go to newer/older posts for different aspects of the guitars:
https://schreinerlutesandguitars.blogsp ... rring.html

Yes Clay, I know about that blog. You were one page or so away from the detailed post on the rope inlay

https://schreinerlutesandguitars.blogsp ... nding.html

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Why be normal?