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The way I've had my top and back & sides sets stored has been a point of irritation for years. I had them stacked on various shelves and typically the sets I would want to look at or use would be at the bottom of a stack which meant unstacking and restacking, sometimes on a high shelf. I finally got around to reorganizing them. They are now all on two shelves that take advantage of the 11-foot ceiling so that they are up and out of the way, and they are stored on edge so it's much easier to get to individual sets. The back & sides sets are arranged up top from Ambrosia Maple through Ziricote.

I need to fill that empty space quickly so it doesn't become a magnet for more wood.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Cleaning up the binding on this one, I spend entirely too much time thicknessing veneer

Brian, that's a very well executed piece of work, and that top is very tasty.
I'm sure the owner is going to feel privileged.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Thanks Colin! This one is for Guitar Salon International so I'm curious who the owner of the guitar will be! I've sold a few guitars through Siccas in Germany but this my first through GSI; it's a bit surreal to see my name on their website now considering how much time I've spent there

https://www.guitarsalon.com/blog/cs-brian-itzkin-2024

Bravo Brian!

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Hutch

Get the heck off the couch and go build a guitar!!!!

Your instrument absolutely belongs there, for a short while I'll bet. Outstanding!

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Measure Twice,

Karl Borum

I'm still very surprised that you can carve an instrument using tapping and scratching. I did spend a lot of time planning out what the low point of the arching should be. It goes from a 13mm rad, to a 110mm rad. Somehow you blend them in. I wanted it to be a pretty high arch. It is probably about 22mm, but my thickness gauge only goes to 10mm! I was going for about 21. I roughed it to a little under 23, and probably took off at least a mm. I put a full curve in at the edge of the C bouts. The poster I have of a Guadagnini viola has a thick, almost flat edge.

This is close enough for now. The arching will change some after the f holes are cut in. I won't do that until the inside is roughed out. The area around the f holes change because of the holes. I'l do the outside of the back next, trying to get the scratch sound the same. Then work on the insides.

The arching went VERY fast after getting the recurve area in. Even doing the recurve was faster this way, than doing it last. It is tapping and scratching, and cutting away the high areas; but you can see and feel the high areas too.

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Why be normal?

Ken, are you saying that you are using the scratch and carve method to do the carving of the outside of the plate, before the inside is carved out at all?? I envisioned it working once the plates were mostly carved, inside and out, and for final thicknessing.

"This is close enough for now. The arching will change some after the f holes are cut in. I won't do that until the inside is roughed out." Ken N

Next time I make a carved plate instrument I'm definitely going to try the scratch test.

I have trouble picturing how it would work on the outside of the plate before the inside is carved. Also how it wouldn't cause visible variations in the outside surface you wouldn't want. Carving to scratch tone on the inside surfaces should do the same thing and not disturb the visible surfaces. It's not like wood is a uniform density material and I'd think variations in density would influence the scratch/carve.

Or am I missing something as I work thru this in my head?

Thanks

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Brian R, Wood Mechanic
N8ZED

Brian, It just works. In one of the videos of Peter Westerlund, he shows that it works on a plaster cast of an old instrument. You can HEAR that the outside is pushed out from the bass bar. It is just a solid piece of plaster. You can't see the bulge, because it is spread out over a vey large area.

I have done it after it was rough carved too. The archtop belly was already roughed inside and out, and it was tunable. I carved the little baroque uke braces with scratching. I even tuned the bridge on the test viola using tapping.

I've been doing it to some extent for a long time. A violin maker who started by making harpsichords used Area Tuning. Keith something. Keith Hill. You can't really thickness a large harpsichord soundboard with any sort of caliper. So you tap. But he was only using it over smaller areas on the violin, and tuned them to different pitches. Now you CAN hear all kinds of pitches when you tap. Depending on where you hold it, and where you tap. The guitar belly has tones all over, and the low tone will be lower as well. Way lower than you might think. But that tone might be your ears putting the higher harmonics together and giving you the low A below the guitar E.

For tuning you aren't really listening to free plate modes. Those are cool, and you can hear all the overtones; but that isn't what you are doing. In the area tuning by the harpsichord maker, he damped the area around, and I think he got the notes from the tapping with the edges held down, like you could do with the belly of a guitar clamped on a fixture, and carving the braces. I haven't done that yet.

The outside shape was even tuned. The ledge has to be pretty regular, a high spot on the thickness, will make it seem like the edge is too big.

Carving this top, I roughed it to the recurve, and got any bulges out of it. It went really fast after that. The archtop was carved inside first, like I usually did, and it was good. The experiment viola ended up with an inside that was the same as my usual inside first plan too. All catenary curves.

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Why be normal?

Thanks Ken. I watched a couple of Westerlund's youtubes and I can see how it works for him.

Next time I build with carved plates I'll give it a try.

Always nice to see a new technique.

Years ago I bought a set of tuning forks and I've used them to test resonance of guitar plates, that's like using a sledge hammer compared to rubbing your fingertips over a surface and listening, but it tells a story too.

But I use my fingers a LOT, like a magnifying glass, its better than your eyes at seeing surfaces.

And some pieces of wood just sing with very little prompting, just picking them up and you say, WOW.

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Brian R, Wood Mechanic
N8ZED

Last piece of my #3 Dreadnaught. Installing it shortly

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Measure Twice,

Karl Borum

Getting materials together to build a mandocello. Red spruce, Indian rosewood, curly maple binding, Khaya neck blank. The last mandocello I built had five string courses. This one will have the standard four courses.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Nice, Jay! I love these types of pics. All the potential laid out in front of you. So cool we get to turn a pile of sticks into something enabling musicians to express their artistry.


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Finally got some strings on this spruce and African Blackwood guitar. The perfectly quarter sawn Blackwood back and sides was a score from LMI 3 years ago, I really miss those folks.

That's beautiful guitar!

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

The sides are now bent for the new mandocello.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I have the outside of the back tuned now. A thing about the tuning. You can chase the tuning forever. The closer it gets, the less it takes; just a light scrape, or maybe later, some sandpaper to tune it. It is mainly getting rid of lumps and high spots. It is higher than I thought it would be. Both were about an inch thick, the belly was a wedge, so I didn't really measure the middle, just the ends with a caliper. I set up a 1" dial indicator, and I guess about 23mm for the back, and 24 mm for the belly. I was going for about 1.5 to 2mm less.

But I think the high arches look cool.

I started laying out the f holes last night. The older Guadagnini's had the cool oblong terminal holes. I have them set on the f hole angle. It has wide f hole spacing. I'm going to give it a wide bridge to suit. Yes. I don't follow rules. The c bout is 45% wider than a violin c bout. Why should the bridge only be about 10% wider?

"They" say that closer f holes make the instrument more focused. This one was wide, and the guy trying to sell it at the high end shop said it was the best sounding viola they ever had in the shop. From the picture, it looks like the bridge is a few mm narrower than the f hole spacing. My spacing is 59, that would be about 53. 52 is the widest bridge that I've seen listed. I can cut a blank from a slice of nice maple, and make it any width and shape that I want.

I see from the photo that my bottom terminal holes are overdone. That's why you draw them before cutting them.

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Why be normal?

Greetings from Montana. I have previously built a baritone ukulele and an F5 style mandolin. Both turned out much better than anticipated. This is my first attempt at a guitar and my first top bracing of any consequence.

I would be interested in any reaction to my bracing especially whether they look too light or too heavy or just plain ugly. This is a rendition of a J185 with redwood top, walnut back and sides, laminated walnut neck, and Sitka spruce bracing on the top and mahogany bracing on the back.

Thanks in advance.

Gary Davis

Untitled by Gary Davis

Vacation season is over, time to build a trio:







Brad


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Well, the bracing is most certainly not ugly and it doesn't look over braced to me without knowing how tall the x-braces and tonebars are. The braces look nicely shaped and finished. I like the look of the x-brace joint with the faired-in cap.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Prep sanding this deep body 13 fret L-00 for finish. This is the first of the batch of 4 I’m currently building to make it to the finishing stage.

Red Spruce/Mahogany with Macassar binding and Ziricote appointments






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Sorry again for the duplicate pics in my post, Tapatalk has added multiples of my first selected photo attachment the last few times I’ve posted and I’m not sure why.


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Looks great, Zac!


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Molds for the new shape underway!




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I sawed the f holes in the viola the other day, and yesterday I was carving one of them in. I leave that area thick because once the holes are in, the arching curves in around them. You can see the huge difference. I did have to lower the height from 23mm to 21mm to match the back. The pitch of the flatsawn Birdseye is lower.

The tips of the wings stick out on the inside. That is better than sticking out on the outside where the might get knocked. I already had to glue a piece of the top wing of the f hole I am working on. Starting to carve the shape of the terminal hole with the knife, it snapped off. There is just a saw cut on the top, and it was full chips, and pressing against it. I glued it back on but I stayed away from it when I worked on it after that. It will be fine today.

It is still very stiff. I do like tap tones as a reference to see where I am. Right now it has dropped to G# on the low E, D# and then A# on the B string. Looking at a chart I printed out, it is 104, 156 and 233 hz. That is probably around a fifth lower than a violin, so that should be good. Tap tones don't really mean a lot; but if they are really high, it is probably too stiff. If it is really low, it could be too flimsy. The thickness is around the the the f hole, and a ways in from the edge.

I also still like to check the thicknesses when I get closer; like now. Most of it is still a little thick. But I mark thick areas, and thin areas; on BOTH sides to check for high spots.

I also like to check weight. I'm guessing it should end up around 100g? Violas are all over the place size wise; but this ming be in the middle; about 16 3/8" or 416mm. It is pretty wide too, and the wood is not light; .47 Englemann (I measured it twice!), that still gets fuzzies if you cut it wrong. It's 129g right now.

All of the actual carving has been guided by scratching and tapping. You find a high spot, and drag a plane blade across the area lightly, and it grabs a tiny sliver.

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Why be normal?