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I find the necks far more demanding than the bodies of violins and guitars. Carving a body is just carving. One task. Do it, and it's done. Necks have scrolls, heads, heels, fretboards, fingerboards, pegs, tuners, frets, have to be joined to the body at the right inclination.

Necks are far more demanding. Carving bodies is easy and fun!

Yesterday I got a lot done. The night before I glued on the headstock veneer. In the morning I cut the profile out, and smoothed it up. Drilled the holes for the tuner. I had to plane a wedge in a scrap of pine to make the back of the head flat. Double stick tape. It worked. Get the truss rod cover to fit good.

Now I have to do some geometry to see how losing 2 frets of length to the bridge will change my bridge height. I don't know how short the wood I'll have under the tune a magic can be, and still support the small metric threaded rod. It will change the string angle too. The lower the bridge, the more acute the angle. I think I had it at 13-14 degrees. My other is at 15, and seems fine. Violins and cellos they measure the included angle, so 158, 156, 153 or so for violin, viola, cello. Or so they say.

My other arch-top rose some, and the adjustable bridge got too short! I had to file wood off the extension of the fretboard. After that initial load, it has been stable; even changing to 80/20 strings from the nylons that were on it.

I still have to finish her filling the fretboard, and put a coat of Osmo on it. Press the frets in. Make the frets nice and pretty. Then I can see about the angle.

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Why be normal?

Since the fretboard has a radius that goes from 7.25" to 12" I decided to make something to pre bend the fret wire. Easy enough to make up 4 patterns with different radii. I cut them out, and found that they are patterns only. You can't bend the frets with them!

Well.

They will be helpful patterns! And it didn't take any more time to make them, than it did to figure out the radii for each fret.

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Why be normal?

I got my frets cut to length and cut away for the binding. I rounded out the ends somewhat. The tops are still full length. The neck is still straight, so the sides of the fretboard are not finished.

I did put some finish on the fretboard. I took a few drops of Osmo satin and stirred a tiny toothpick of Azo green oil paint into it. I tested it beforehand, and it gives the light side of the curly bubinga a nice glow. About 1/4 tsp in a Tbs measuring spoon. It was more than I needed, but you have to have enough to stir! I work it in with fingers, and then rub off with paper towel. I let it dry a while, then I buff with a cloth until it is not sticky at all. Very little finish.





While that was drying I decided to get the plates finished. I cut the outline to size. There is really no other way to get the edges right. I marked the inflection line, where it changes from convex to concave, and both top on back were pretty even. Cool. Even the edges were pretty even.

The back started way too stiff. The outside was shaped, but it was way too stiff. I cut the inside deeper to make the middle about 4.5mm. Still too stiff. Then I went to about 4. After going all around the arch in every position, it seems about right. Maybe a little stiff. There are "windows" or "lungs" where the thickness is under 2mm. It may seem alarming, but it is fine.



I just use scrapers at this stage.

I still need to do the top of the back. I might need to go on the inside, and thin the recurve out, I haven't measured that area yet. I like the way it looks on the outside, so any thinning will be on the inside.

Unlike most makers I make my arching on the inside. The outside looks pretty normal, but it is the arching on the inside that makes the arch. The outside determines the graduation. The back used a way that I used on the Montagnana violin I just finished. Diagonal cross arches, and then arches perpendicular to the edge up through the diagonal arch to the middle.

What this does, is the cross arches are tighter, and stronger. They have a shorter span, and are somewhat taller. As you make them deeper, the area between the middle and the inflection line can get thin.

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Why be normal?

Hey Ken,
Interesting thread, I've been watching your progress and it is coming along quite well. Not sure I would even try to build an archtop at this point in my progress of learning to build. So many variables in sculpting a top and back I will stick with simple stuff for now... maybe one day. That back plate is a beautiful piece of wood, can't wait to see it in finish and hear how this sounds.

Keep on posting, I"m watching

Cheers,
Bob

I added something I didn't think about. Putting some plastic bags back into the plastic bag holding all the plastic bags, I found a little bag that had something in it. Wow. StewMac pearl dots. I forgot about those. How did they get in there? So first I put the 5 side markers on my first guitar, the other arch top, and it worked fine. I made up some pseudo brad point drills in 4, 5, and 6mm, and then a 1/4" one that I had trouble with for some reason. Why I had one 1/4" I don't know. The drills didn't work too bad, the 1/4 was the worst one.

A learning experience.

Before that I had pounded in the frets. They are all down, and they match the fretboard. They seem to be dead flat. You can only measure toward the edges and in the middle, because of the conical board. I made up some pattern to put them in randomly. Maybe it worked. Maybe the neck is just stiff, and frets aren't about to move it any. I'm guessing it is the last one.

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Why be normal?

Ken,

Your fretboard looks really good.

Do you mean when you put the frets in it put back bow in ?

Cheers,
Bob

I do use a couple handmade measuring tools for carving. Basically violin making tools, but Ken Parker uses them too.

A thickness gauge, or a stabber. A tool used by Stradivarius. It marks thicknesses. I used a 1mm pitch bolt ground to a point. A hex milled in a piece of brass at the top makes it easy to drop it down, .2 or whatever mm at a time. Deep punches in soft stock, like this cedar decking is NOT recommended, unless you like dimples on the outside. I use it inside and out, depending on what I'm doing.



I also measure with a gauge. I use a tenth, mm gauge. It only goes up a little over 10mm, so stock has to be roughed down to use it. I like analog over digital. When working on the edge, the thickness changes quickly. You can watch the dial spin, and see when it changes direction. That is a thick spot. It is far more user friendly than digital for me. A tenth is overkill, but it was really cheap on sale when I bought it; probably $30 or something. It isn't really hard to use because one spin around is .04" and that is as much variation that you get when finishing an area. A violin can rapidly change from 2.5mm to 5 or 6mm in less than 2" in the center bout. There I'm just looking for a smooth, even, drop; in to out, and then up and down.



I'm working on the edge of the back. Some on the outside right at the edge, and some on the inside at one spot in the mid section, and transitioning to the edge. The right side (treble) is done up to the waist. The rest isn't done yet. Maybe you can see the difference. We're talking .5mm or so, and that's curved. The chain is the 18" chain I use to check the arches on the inside. They don't go all the way to the edge. I like them to be as good as I can get them. The silver is coming off the chain. I've used it a long time. A longer one would be better for arch tops. You definitely need a longer one for cellos.

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Why be normal?

The back is getting to where it feels pretty good. Maybe a bit too stiff yet. Watching Ken Parker's videos doing bracing, and I see that I needed to look at how I feel stiffness. You can't just grab it on the edges, and flex it. You have to find how you can assess the stiffness everywhere. I found that the belly I thought was floppy on the edges was simply a case of very stiff flat sawn edges, and then a rapid transition to a thinner rift sawn area. It was just bending there.

One way to get some idea of being in the ballpark on violins and violas is weight and tap tone. Yes, they will be somewhere close usually, but good arching, and good wood will be lighter and stiffer. I have no idea what an archtop belly or back would be, weight wise, or tap wise. This guitar is so much smaller than the usual archtop. My archtop is 16" and sounds brighter than my 12" Staffer. Of course the one is 2.5 pounds with nylon strings, and the other 3.6 pounds with 80/20's.
This back seems fairly light, 194g. But it has a strong low tap of 160. There are a couple small ones at 107 and 124, but 160 is massive. There are 4 very strong "ring tones" at 368, 405, 439, and 486! That is higher than anything I've made. 368 would be a very "good?" violin? Under 350 would be more normal.

I was thinking that I was 2X's the size of a violin, and 2/3 of my archtop; but maybe it is smaller than that.

I would think that maybe this back is still too stiff; but I'll see how the belly goes first.

The belly is very hard to get smooth and even: with no tears. Small cuts with a thumb plane is the only thing that seems to work. The winter wood is very hard, and the summer wood very soft. Ripple city. I had the bars fit to the belly, but I thinned it out more, and they will have to be re-fit. I'm working on the inside and the outside together. Keeping stiffness with arches on the inside, and even flexibility with the outside cuts. I'm cutting the edge from 4mm to 3.5mm. The back is at 3mm. I've heard comparisons of parallel and X braced arch tops, and have always preferred the parallel. The x braces always sound like they are held back to me. Muffled almost.

Maybe that is what Parker is addressing with his tiny braces?

Granted. I've never played ANY archtop, or any guitar at ALL, except the 3 I made, and my garage sale classical. So I'm just hearing recordings on YouTube.

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Why be normal?

This will be an original design that I have great interest in. Drive on, Ken.

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"Act your age, not your shoe size" - Prince

On such a small arch I would question the need for bracing at all. Certainly I would think very small ones.


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Bob, I just noticed your question. No. I think that it is still perfectly flat. I find it very hard to sight the tops of the frets with a straightedge over them. You can feel rocking if there is a high fret, but to see clearance? That's a whole different thing. I can see it on violin fingerboards, but the tops of frets? Not so much. I thought of a bow, with a black string or something like that. Something that would be straight, and not bend. Maybe the round edge of the string would help.

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Why be normal?

I was thinking the same way. On a violin, the f holes really loosen the top up. The treble side of the bridge is supported by the sound post, and the bass side by the brace. The bridge can rock on the sound post fulcrum, and the brace can help transmit vibrations up and down the belly. But violins have a constant input from the bow.

Guitars don't have that.

In guitars input is minute, and everything has to be conserved. My other archtop is more like a cello. It has big f holes that did loosen the top. Curly redwood is already loose. It has parallel bars. Thinner, and not as tall as suggested, but still probably overkill. The top did rise some, but I wonder if it rose because the bars wouldn't allow the belly to drop some in compression from the strings on the bridge, and the stronger force of the strings on the neck and body forced the belly up.

Maybe, maybe not.

On this one, there is a sound hole between the bridge and neck; but it is right at the block, and the arch rises up from there. The weakening by the wood changing from dead on quartered to rift to dead flat sawn, is the mystery. I'll have to carve it way down from where it was, and see what I end up with.

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Why be normal?

I have the bracing glued on the belly. It is down to 120 grams. I took my cello belly down to 400 from 420 grams the other day too; and it still feels stiff. The model I made is more like a slim English cello than an fat Venetian cello, so I guess that is why it is light. Or maybe I just walk on the wild side. I think that it is still too stiff.



The one brace was glued last night. While this one dries I'll work on the ribs. The one side was the outside of the board I had re-sawn, and the other is the re-sawn face. The other photo shows the hack job that my band saw did. It wanted to walk all over. It's still plenty thick. I'm looking for 1.5mm and under.

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Well, I didn't finish the sides yesterday. I spent 2 hours before lunch (we have lunch at 5, and dinner at 1. I used to work afternoons, and it struck) and got the wonky cuts smooth, flat, and either side could work. The first one is 2mm or so, and down a bit. very even. I didn't check anything, The second is probably about the same, I didn't check it yet. I'll thin them with the scraper to size. The treble side will have 3 thin areas, one will be very thin. The bass side, one one thinner area.

I cringed watching the guy in the French video plane sides. Kept waiting for the snap. I clamp on the end, and work away; generally. Even working away, you have to be sure the sides stay on the table. The wooden German plane is not my favorite. It seems to want to change set. But it works well with a toothed blade, and when it seems to be digging in, I back it out again. Maybe I need to use a Phillips head on the little screw; or find something with a big knurled head, and not a tiny one. They saved money with that little screw.

The toothed blade is first. The little flat finger plane can get spots where the grain shifts, or the wood is just harder than the areas around it.

Then I use the long Craftsman. It has a vey thick blade, and a very thick chipbreaker. It is JUST past the point of the original adjusters working. I could probably fix it somehow; but it works great anyway. It might need brazing, and that is not in my skillset.

The wooden polisher works well, but even it struggles with this Padauk. It has a brass insert that gives it a small opening. The little plane blade works great as a scraper. As a plane blade it didn't stay sharp, but is makes a great scraper. A couple other blades were better plane blades, but aren't as easy to get to work as good scrapers. Decent scrapers, just not great scrapers. The harder steel is just more difficult to burnish a burr on?

Another hour or so and they will be done.

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Why be normal?

Checking to see how things line up. Make sure the slot for the neck is big enough. Make sure the hum bucker slot is sort of even. Make sure the neck can be on the centerline. Find out that the sides that I probably thought were 60mm wide are only 58, and the block is a little TALLER than 58mm. I need to add 3mm shims on the block to raise the neck up. The neck would look stupid sunk into the top.

I might mount the tone hole fake humbucker on the block. The surface that is opposite the block of it will probably move. I don't know how much; you don't know until it is glued on the ribs. But it might not want to stay glued on. I don't know about that yet. Maybe I'll glue the sides and blocks on the back, and clamp the belly in place and see how much movement I get. I'm building on the back anyway.

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Why be normal?

Last night I bent the ribs. The treble side has a really tight curve on the arm. It is the smallest radius on my violin rib bending arm; or a little smaller. About 3/8" I knew it was small, and it is only about 1/32" thick or less there. The rest of it was no problem. I still do ribs thin; nothing is over 1.3mm. A noted violin maker said to not make cello ribs over 1.5 mm. A different mindset. I guess guitars are looking for sustain. I'm looking not to snap the ribs!

I'm going to glue them on the blocks, with tape holding the ribs to the outline, and then use the little tentalones? to glue them in place. Make linings to match the top, and glue them on the ribs, and then set the top in place, and glue it. I might make some extensions to the side of the upper block to add a little support to the belly. Maybe it doesn't need it, but it can't hurt.

Probably a half round piece of wood to brace the tip of the arm. Just in case.

I got Cello strings in the mail today. I need to set the neck, and start finishing up my cello. I like carving the big things better than the little ones. I like the deeper sounds of a cello too. They are cheap D'addario strings. $54. I had a $50 gift certificate so I was trying to stay in that range. Not very many at that price point, and nothing I've heard of besides the Preludes. D'addario makes Helicore's for cellos too; I have them on my 5 string viola/violin; but they sound different. Most real players, not beginners, play on sets 3-6 times more expensive than that! That is the common range for a set $150-300. These are discount prices; not store prices. Actually they mix and match: usually the 2 low strings from one brand, and the top 2 strings from another brand. They are looking for some elusive sound.

I bought cheap ones. It's my first, and I have no idea what kind of sound I'll get. Let someone else put expensive strings on it?

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Why be normal?

It's getting closer to looking like a guitar:



I was gluing the blocks on the back, and then I was going to put on some supports; especially for the belly, with the sound hole close to the end. A clamp slipped off, and while putting it back on I heard it. The dreaded snap.

I got a crack maybe 2" down along the block by the cutaway. The very spot I was worried about. I should have put the extensions on first, but I wanted to see exactly where they would be.

So.

Make up an extension to support the split; I hadn't made them yet, and then put some thin HHG in the crack, and let it go back together. Glue and clamp the extension, and wait until morning.

It is fine today. After the photo, I scraped the glue, and you can't even see the crack, on either side.The blocks have made the back sound like glass. Just the one extension, and the blocks have stiffened it up a lot. I'll add one for the bass side.

You can see at the start of the crack how the grain is going. On the arm you can see the grain going the other way. Scraping works better than planing.



If I had it supported with something like a bean bag or something to place under it, I'm sure that it would have been more stable. I haven't made any guitar forms, but I will for the Panormo guitars, because I'll make 3 of them. I've made very simple inside molds for violins, and sometimes just a skeleton mold to hold the blocks. I did make a super fancy, pull apart mold in 3 layers for my cello. It has tapered sides, and the 3 layers made it SIMPLE to bend the ribs around it. I will set the neck with the belly just placed on the ribs, and then glue the back on with the neck already glued on, and then take the form apart, and glue the belly on.



I found that supporting a thin plate solidly in two places makes it very fragile.

Beautiful sunny day again, and tomorrow too. The bottom falls out on Saturday. Just in time for my daughters wedding!

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I have the ribs and linings glued on. The lining for the top is 4mm thick poplar, 8mm or so tall. I had a piece long enough! I bent it somewhat inside the edge of the belly, so the belly fits nicely. I have to do some cosmetic stuff, smoothing up all the edges. Then get the humbucker Tornavoz glued on to the block, and the hole enlarged on the belly so it has clearance, and everything is centered. Then I can glue the belly on.

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Why be normal?

That's coming along nicely Ken!

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Steve Smith
"Music is what feelings sound like"

Looks Good Ken,

Its starting to look like a guitar now!

Watching with interest

Cheers,
Bob

Great thread Ken. I've been lurking along since the beginning. I've definitely learned some new things. Keep it coming!

Well, there is a thread on embracing repairs.

I will start on that next. For now, I'm setting the neck on a cello. Doing it right on the form; the back and belly are not on. I can place the belly on to check the projection at the bridge. I'm using the neck projection, and the fingerboard is engineered to make it work when it is all done. That's the plan anyway. The overstand, the amount of neck that sits above the belly is fixed, and the neck angle. Now I have about 8mm more to drop it at every point, and it is straight, and on center. I started at 30mm up.



Now for the repair. It isn't terrible, but it could have been avoided if I paid attention. The main problem is that I didn't design it right from the beginning. The key for the neck SHOULD HAVE been narrower. 1" nominal would have been good. I didn't have regular sized stock so I went wider. It came back to get me. You can see that I didn't take the taper of the neck into account.



OOPS.

I will glue some support behind it, and glue on a little triangle of rib. But I'll finish the neck set first, to get something accomplished.

It did make me think about the neck design. If I changed the bolts around you would only need 2 small holes in the back to bolt it down.

A little bit different, and it could be adjustable without taking the neck off. That seems like the best plan. It seems like it would work. I like prototypes, that is about all that I build.

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Well, I got the cello neck set. It is as solid as can be just tapped in. I'll have to remember to glue it! I started rounding it out too. It is curly hard maple, and my black handled Iwasaki half round seems to work the best on it.

Now I can get back to the guitar.

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I got the neck all smoothed out yesterday. The mahogany is MUCH easier to carve than the curly hard maple. The neck, with the tuners weight 700g! That seems very heavy. My entire Stauffer guitar weighs 1130g, using the same tuners, with added extensions, and a brass plate!

The tuner base doesn't fit flat on the back, the center is open. The post fit in the holes, but the alignment must be off. I'll get that fixed after I work on the situation on the sides by the neck heel.

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Well I did some cleaning up, and re-organizing, and seeing what I had, and what I need.
I don't need much. Archtop top wood. Maybe a guitar/cello rib bending iron.

I made a new handle for a gouge I've never used. It just didn't work. I sharpened it like Ken Parker, and I think it might work. The handle will work better. I made it so it will just fit in my gouge drawer on my bench. The next drawer has chisels.








I did some cosmetic work on the Padauk edges, and have wood in place as a backer for the little triangles of Padauk at the neck heel. After cutting relief in the neck for the backer wood, I put the neck on, to be sure that everything cleared. Then I decided to see how the belly really fits on.

Not as well as I thought. The waist splays out some, and the lower bout is in some, It isn't quite the same shape. You can massage it around, but not quite perfect. I'm going to tape it all around, and file it so a little of the rib alone is showing. After a little work it is close. Then I'll glue on a b/w/b purfling. It should work, and add a little edge to it. The binding is just going to be really thin black plastic. It will stick out from the sides its entire thickness.
The clamps have 3 sets of bolts: for violins, guitars, and cellos. I made them out of dowels, but I should have splurged for maple or something, The "hardwood" is not very strong.



The next step is filling in the gaps by the neck.

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Why be normal?