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Yeah, it says building but I have questions too! I did one of these before for the Grandsons. It was thick everywhere; the bridge was higher; the neck was longer; it had metal frets, only 5 strings. It was really a 1/2 scale guitar with a Strad shape for 4 boys. THIS is supposed to sound good. It's a small one, 375 mm long, like a small VERY thick viola. A 540 scale, so it should be pitched in G.

The belly is 100 year old or so Eastern Red Cedar that I got from a guy at work when he tore down a barn. Not much was guitar wood, but I got these 2 small tops. It is not very stiff, but it should work. At least it is quartered, the one board cut right through the middle! The back and sides are from maple cello side stock.

The back has no braces, and the original belly had two cross braces. I've seen that people call them harmonic bars. Why? After seeing Bruce Sexauer's bracing, I see that he had one horizontal bar above the sound hole, and the X brace came up high. On this guitar, I thought of doing a double X brace, but like this:



Any thoughts on this? Madness?

On the EXCITING side, I used my Dremel to cut out a rosette! Just a simple thing, I'm not much for bling, and this is more like a little flamenco. If I had violin purfling it would have been EASIER, but the piece I have left is viola. I didn't realize it was 1.5mm thick, the cutter is only 1.1, and that is ALL that it cut, so I had to move it over. The Dremel fixture is not state of the art; but it works. I will have some figured mahogany between the two purfling circles, so I could cut that out with the same setting I cut the groove with.

How deep do you guys do this stuff? I went 1.5mm for the grooves. I'm using a chisel to cut away the space for the mahogany. 1mm or so deep? It should look good:

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Keep the pics coming!

A fun little project ! It looks like you were originally going to do the typical transverse bars above and below the sound hole but changed your mind. On a small narrow instrument like that the bars and maybe three small fan braces might be enough. The bridge being low down on the lower bout I wonder if some sort of lute bracing might work. But don't mind my musings, what you have drawn may be even better.
I like experimenting with different bracing schemes (I often learn what not to do from them ).

Your numbers had me confused, but I'm guessing the 375mm is scale length which would fit with small viola.

For a soundboard so small, that's a *lot* of bracing. There's a danger that the instrument will be very quiet if the top is too stiff to work properly. I'm assuming nylon strings (or gut if you want to be authentic).

It might be worth looking at concert ukulele bracing, as the soundboard is a very similar size. These are either ladder braced (2 cross braces with a bridge patch) or fan braced (cross brace and 3 very skinny fans). Much more and they become nearly silent!

The scale length is 540, around the 3rd fret of a standard guitar. The body length is 375, about the same as the 5 string I made, but 1-2 inches shorter than the 2 violas. The bracing is not really BRACING, but low, very skinny bars, that just add some strength, and keep the strings from bending the belly. I'm thinking 4-5mm wide, and starting at 5-6mm tall, and tuning after glueing them on. The E modulus is only .88! I has a lot of movement now, even as small as it is.

The belly wants to bend concave too, it doesn't lie flat. If I induce some convex with the bars; just that would stiffen it some, wouldn't it? Is it easier to collapse concave, than convex? I don't know.

Why do they call them harmonic bars? They look like sound killers to me! Like I said before, I don't know anything.

Learning how to play on my Archtop, and the G string keeps getting in the way. The other strings don't seem as bad, but short fat fingers don't help. Is it just that the diameter is bigger, or does the radius contribute to that too? That's just something I thought about yesterday when I couldn't play notes on a C chord without my fingernail buzzing the G. I have 7,5 mm spacing on the strings at the nut. The design for the baroque is 7.8-8.3 between pairs, so a little more room. And I'll only have to reach across 5 strings!

I thought of guts, the only drawback is price. I don't know where to get nylons for a baroque. I thought of stringing it C c, F f, Bb bb, d d, g g. with a low Bb on the third string. Adds a bit more bass to balance out the high end. It's a guitar, not a mandolin! Playing the top 4 strings and the bottom 6 strings on my guitar they sound cool. I can't play them all at once though!

I have questions all the time. My mind doesn't stop.

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Regarding depth of rosette, 1mm to 1.5mm is a good range. You can even go under 0.5mm and use sliced veneers, although they're difficult to cut into shape without splitting, and of course you have to be careful not to sand through later. Really the only limit is that it can't be more than the total soundboard thickness Look up Hakone box marquetry. Those guys make gorgeous veneers the thickness of a single plane shaving.

Regarding string spacing, I don't know why G would be problematic unless one or both of its neighbors are higher than they should be. You probably just need a larger nut width. I have very large hands and can't really play the common 1 11/16" (43mm) steel string nut width at all.

And for bracing, it all depends on the thickness of the soundboard and height of the braces. For small instruments like this, I prefer no braces at all in the active area, except for the bridge itself. This one is 290mm lower bout width, low density redwood (comparable to western redcedar), about 2mm thick. 8 years old now and no problems.

But the bridge is a rectangular type and extends the width of the waist, so it is a pretty substantial brace compared to the slender moustache bridge on yours.

I think your double X pattern will work ok. I'd make the upper legs of the lower X relatively tall where they cross beside the soundhole and meet the the upper X. It might not be a bad idea to add some wide flat finger braces extending forward from the corners of the bridge for more horizontal spreading of the load, like what Laurent Brondel uses on his steel strings http://onemanz.com/guitar/wp-content/uploads/sites/2/2014/12/IMG_1160.jpeg

That bracing looks light. The Archtop I made used curly redwood that is .35sg. It's carved, and the 2.5 to 4. or so thickness with low parallel bars works fine on it with heavy nylon strings. I don't understand nut width. It seems that they talk about absolute width, and I want to know the e to E length. I measured mine just now. It's 1.5" and 1 3/4" total. Is that narrow?

I know I didn't leave enough on the sides, from the edge of the neck to the string. I thought I had 1/8" but it isn't nearly enough. Rounding the tops of the frets off, the low E is easy to push off the edge. The high e I don't push back on, so it isn't a problem.

I glued on the inlay. The purfling, and insert fit perfectly. I only defuzzed the bottom edges. I went .o6" deep on the center insert. Planed most off with that nice convex Lie Neilson plane, and then scraped it. Then I re-checked it on the quicky fixture I made up for tuning, and took some more off the edges. The hole didn't really seem to make it that much more flexible, if any. So I checked it, and I get .03-.o35" movement with a 4.5 pound plastic jar of apple juice. Checking the back it has .02 or so.

I guess that it has to be free to test deflection. I'll set that up tomorrow.

The back has no braces at all.

They are both about the same thicknesses. 3-3.2mm in the middle, and 2.2-2.5 on the low spots around the edge.

Now I'll have to work on the bars.

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Yeah, 1 3/4" is really narrow for nylon strings. Not only are the strings themselves fatter, leaving less space inbetween them, but due to their elasticity they need higher action than steels, which means sinking your finger deeper into that narrow space. And if your fret ends are over-rounded, then the effective nut width is even less. I'd go width 1 7/8" (48mm) as a minimum.

You are correct that E to e spacing is an important dimension, but it can be changed to your preference by making a new nut, whereas the total nut width is permanent, so that's why nut width is listed more often. 1 1/2" is good for steels, 1 5/8" for nylons.

Oh, and make sure your edge space increases as you move up the neck. The string stretches more easily toward the center, so it's easier to fall of the edge there. I like around 1/8" edge space at the nut, and 3/16" at the 12th fret. With fret ends shaped to maximize usable width.

3mm sounds really thick for such a small soundboard, especially if it still feels stiff as a board when it has a hole in it In that case nevermind on adding finger braces. You could probably carve the lower X legs down to nothing before the bridge and still be structurally fine.

I made up an X brace, and glued it on, we'll see what it does when it's dry. I planed the bottom using an idea that someone here had, but I can't find it. Clamping the brace on the middle of its side, you bend the ends out; I used two deck screws; and you plane the end. It gives a perfect arch. I thought it would turn it into a spring, and arch the top some. I tried, it wasn't strong enough. I made it a lot more arched, and it still doesn't seem to do anything, you can fairly easily psh them down flat with your fingers. We'll see. After it is glued I can thin the bracing, and the soundboard, until it does what I want.

I don't have a solera, or a go-bar set-up. So I'm just gluing it with spring clamps, with a couple wood clamps in the middle.

Speaking of a solera, it seems like everyone has their own idea. That's a question for another time. This instrument, that doesn't have a Spanish neck, but still has the neck even with the blocks. The fingerboard (tied frets) and the tang on the end of the soundboard are both about 3 mm thick, and in line. The strings do not have much clearance over the body. The bridge is 9 mm high, so I should end up with 3 mm clearance at the 10th fret, that is just before the body, and will have to be wood, and about a mm or so. When it's done I'll see how much it moves. With the baroque you can change frets, and tie the strings on higher or lower.

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What are the dark dark lines in the top?

It was 100 year old barn wood. A few of the deep grain lines didn't quite clean up. Not more than .02" at the most. I filled them with some Zpoxy. The board was dark grey.

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I glued on the struts, and trimmed them, and tuned the outside. I checked the deflection of it before bracing, just placing it on blocks about 12.5" apart, around the distance of the end blocks. It was .170 with the 4.5 pound weight in the middle, and .100 at the bridge. Now it is .075 at the middle, .05 at the bridge, and .035 with the weight above the sound hole, with the indicator on the inlay below the sound hole.

The back will have no bracing, and it deflects .100" I guess it's in the ballpark. It's a smaller instrument, so would it use a smaller deflection?

I think I'll start gluing the neck and back on tomorrow.

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Those old cracks are going to open up on the outside eventually.

Thinking about those lines, I'm not sure they were cracks, but the wood isn't the best, but I just have two pieces of stock for a couple of other guitars. So I found a hunk of Sitka that needed a wedge cut off it to free a viola body. It looks like a lot of work, but I gave it a go.

First I had to cut the wedge off. It won't fit my band saw even after the wedge is cut. I need 110mm, and the saw maxes out at about 100mm. So it is the monster.



After I have the wedge I cut 1/2 inch or so off the small end, and marked it for the first side. Then I knew where I could cut it to get rid of the outside edge of the wedge. That one had some insect holes, and a sappy section on the edge. It is easier to cut up and down like this:



You can see the pocket, and the holes. I'll have a couple in the lower bout. Oh well. I planed them down to about 4mm thick, and the bench was moving all over. I thought the big bench wouldn't do that. My work mate was crazy.



Now I'm ready to glue. Tape on the board, glue in the pot, and warm it up some with the gun. It's still only 62 down there. It was 65 after I was done sawing and planing. Imagine that. It has a Harry Potter mark feel to it, but more like a double helix pulling apart. There's an afternoon.



It looks like I might replace the Cedar top. We'll test it tomorrow after I plane it flat. It went WAY faster than I thought it would.

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Well, I have the Sitka almost thinned out, and tuned. It is difficult to get even because of the bear claw. I thin it out white a bit more in those spots. The Cedar is pretty evenly thicker in the middle, and thinner on the edges. The Sitka isn't.

I have the outside face smooth. It had some tearout from the roughing. I used a plane I bought for joining that I really only use for final joining. The blade can be set really fine, and the mouth is outrageously small. I found that it is VERY GOOD for smoothing up guitar bellies. Just lay the belly down, and slide the plane towards you. No clamps anywhere. It took a while, but I got them out without doing any more damage. Then I got it down to an even 3 mm or so from the back with my big planer to keep it flat.

The cedar one still feels pretty good. It is flexible side to side, and should be stiff enough for the strings. I think that I'll put a few cleats, and maybe even a couple of splints in it per Barry Daniels suggestion. I thought that I was posting using my Kindle Fire, but somehow sent him a PM. I guess it is better than sending a private email to everyone on your contacts. I've filled sap pockets from the back side before, so that's no big deal.

I can use the Sitka top for another baroque, maybe using the two transverse bars to see how they work.

This rosewood plane is very nice for polishing.

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]I glued the back on yesterday afternoon. I will definitely make a work board for any other guitars, and build them on the belly with a Spanish neck. It seems to be MUCH simpler. I don't have a lot of luck with the bar clamps I bought at on sale at Woodcraft. Sometimes they hold, sometimes they won't. Why make a product that doesn't work? If you have to cut costs so the MAIN feature of the tool doesn't work; then don't make the tool. Seems to make sense to me.

Are there some brands of bar clamps that work ALL the time?

I like the idea of having the belly, neck, and lower block glued, then bend the ribs, and glue them on right then. Glue the back on, WITH THE SAME SETUP, and then it's just finish work. All I need is a board, and some threaded rod. They sell that stuff at box stores, don't they? I guess I need a hacksaw too.

Now I will reinforce the Cedar belly. The guitar is just a little guy.

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I use the Irwin Quick Grip clamps in various sizes, and they have never let me down. Still have a bunch of Klemmsia cam clamps and Pony bar clamps, both of which are great and I've had them for 40 plus years, but the Quick Grips are my favorites.

Very cool little guitar!

Dave

Irwin Quick Grips? Those are the ones with the blue and yellow branding? Good to know, thanks.

Yesterday I cut out the black wood. It was surprising how deep some of it went. Filled it in with some cutoffs from the Sitka top, and now, after cleaning it up, it looks like reconstructive surgery; reconstructive, not plastic surgery; it isn't that pretty. It was easy to do. I have a skinny tool that works great for that. I made it out of a 3/8" bar of HSS. Why I made it, and why it had to be so long I don't know. That's a whole lot of grinding. It looks like it turned it back on the lathe first.

I found a piece of wood that might be some kind of Rosewood that I can use for the fingerboard and binding. It is just wide enough for the fingerboard; and just long enough to go half way around. Cool.

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Well, this guy is gonna have a bear claw top. I was using a coping saw to cut to top where the tongue is so I could fit it with the fingerboard, and glue them on. The top started spitting in my hands WHERE THERE WEREN'T ANY BLACK LINES. Nice. Right now the spruce has no bars or tone hole, and it feels about the same crosswise as the cedar top. It flexes a lot when just sitting the ribs compared to the cedar with the bracing, but testing with the 4.5 pound jar it moves .110" compared to .125 for the back, and .075 for the cedar top.

Now that the back is glued on, it just moves a little with gentle pressure. Feels about right.

I think that I'll use it as is, with two transverse bars like the original. I don't know anything about them, so I'll have to see what I can find. Do they go all the way to the liners?

I found yet ANOTHER reason to use the Spanish method for my building. My eyes. I've noticed I have trouble lining things up at times. Running the CNC mill, and even watching a tool come down on the lathe; that I've watched for over 30 years would startle me, because it seemed like it was going too far. I was always hitting the feed hold because it looked like it was in the wrong spot. Never had that problem before. Used to see great. Could read the lettering on an 8-32 tap. Easy.

I noticed that for some reason I decided that my lower block was off center, and I moved the rib seam to where I thought it should be. I think I probably checked it twice. Well, I lined the neck up to it perfectly, and it is off 4 mm or so. To me it is no big deal, the body is not symmetrical and it is offset some too. Only the belly would be noticeable with the cedar, with the spruce, the seam isn't apparent, unless the varnish brings on the light/dark shift. The grain on the spruce and the maple is pretty straight.

The sides are on an angle too. IIRC, I was thinking about doing a cello with a smaller back than the belly to make it more comfortable, and when I made the form for the guitar, I added that feature to try it out to see if it would work.

So building on the belly would eliminate the problem of centering. But now I'm stuck until my purfling comes in. I can always turn ten pegs. That should take up some time.

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I think you made the right decision to replace the cedar top. Cedar can be very good or it can be very bad. That piece didn't look too promising.
As I've said elsewhere, center lines are over rated. Torres used mismatched tops and often the joint was other places than the middle. He was more concerned that the wood have the right qualities than that it be cosmetically perfect.
The little guitar looks like it is coming along nicely.

Ken, it looks like you are having fun building, and to me that is the essence of instrument making. The world has enough "perfect guitars", why not try something else. If I can do a step by hand without power tools, I will choose to do it every time. I like to work in the quiet.
Clay, I have a feeling that Torres used whatever he could get to build with. He was as poor as he could be and no one would pay him enough to buy better wood, but that didn't stop him. When he finally got the recognition to command higher prices, he was running out of years.

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I think the bear claw looks cool too.

Yeah, I'm a fan too. And it is easier to see on a guitar than a violin or viola.

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Hi David,
Nice to see your post. I drop by your website every so often to admire your guitars.
I believe you are right about Torres - he never had the resources of the French or German makers. But from his carpentry background he was able to select and optimize what wood he could get. Rather than make a matched set of poor quality he would use two or more mismatched pieces of good quality.
Most of us are lucky to have excellent materials just a click of the mouse away.

I've been working on the pegs. Like everything else on this one, they are very minimal. I used the drawing on the plan, but it they are on the small size. All TEN of them only weigh 24 grams NOW!

I have a little fixture I put the blocks in to turn the shaft, then I blocked them into shape in several steps, and now they are getting the profile on. They'll need the little beads at the hilt? of the shaft, and then I'll turn them around, and turn the taper on.

The heads get thinned last, but I have no idea what the shape was meant to be, because I don't have a photo, or a side view drawing.

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