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I got a crazy idea for a fast? little build. A Wes Fall arch top. One of my apprentices at work always says he's waiting for his guitar. He always complained about how much Gibsons were. So I thought I make a fake acoustic one. Home Depot cedar top. We'll do that first, to be sure it will work! mahogany neck, Padauk back and sides, the top face pickup will be a sound hole. It might need a port at the upper side; I don't know.

I'll nave to pick up some pickup covers, and cut the centers out. Would shops just have some laying around? I don't think I'll put the knobs on. I am thinking about using the adjustable bridge though.

I drew it out on the bottom, and this is what I have:


An hour later, and the diagonal arches are pretty close. This it the way I do violin and cello bellies too; but their shape is much different.


Turn it sideways in the vise, and I bring the cross arches in, and then smooth it up, using my fingers to find high spots. I use a 18" smooth chain I bought at Walmart to check. You can check every spot that way. It is good enough for being roughed out. 12mm deep at the bridge or so, and fairly flat across the middle. Almost an hour to do that.


I use a drill with a post bolted on to the press to drill holes leaving 6mm or so of stock. I'll plane it down till the dimples are almost gone and see what I have. I can cut the outline after that.


Tell me I'm not the only one that has tried this.

I have no Idea about neck angle or anything yet. It will use a tailpiece.

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Well now I have to get some an adjustable bridge, and a hum bucker cover, or at least dimensions to make a couple blocks up to see where to go with this. I think a 10 degree angle over the bridge will work. It is still VERY thick at about 6.5mm. The basic shape is there, but the edges will come down more with thicknessing.

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I lov4e seeing your work Ken. Look forward to following it.

Doing more refining. The length is effectively very short, so the outside long arch is like a radius.



This is the inside this morning. You can see where the sound hole will be. It is a little more than 1/2 the surface that it should be. I think. Side port?



A bit of a problem on the front side. The drawing I was using showed the entire pickup cover, so I was thinking that it was way wider than it really is. I haven't looked at an electric guitar, let alone hekd or played one, so I am clueless. This will be an acoustic, but I want a fake pickup.

In looking LP's up, I see that the drawing is a more rare newer model, an ES 775. It works for what I wanted. I'm going to make the block all the way to the tone hole. When I put the drill holes in the outside, I have one on the bass side that would make the thickness, 3mm there. Not a terrible thing right at the block, but I was planning on angling the thickness of the top from 4mm at the edge to 6mm by the sound hole in the neck area. Only because it looks better that way. I think. I may carve it down so it looks good on both sides, and fill the hole with a simple patch if I have to.

I drew it out with a trapezoid hole, but it would look stupid.

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Well. Lookin at the drawing I need to measure some things over again!

5 minutes later. The initial placement was right. Somehow I moved it!

Cool.

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So are you using a humbucker cover to fill the hole? Or just make it the same size and shape as a humbucker?

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

I think a wooden rectangle, the size of a humbucker cover. It might be easier to fit to the hole. The top needs to be angled with the strings. A regular cover might be hard to cut the top off it, and make.It look clean.

I still need a lip around the bottom edge of it to cover the one hole. I thought the humbucker was wider from the drawing.

I roughed out some more by the NEW sound hole, and it makes.much more sense now!

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Wooden pickup rings are available, and pickup covers with open tops are also available.

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

Thanks Chris. I had no idea.

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I have no idea about a lot of things! Like they come with 16 fret necks! Who knew? I was watching a video to see how the necks we attached; because I have NO IDEA. It seems at least the fretboard, and maybe more is above the top. The guy said 4 degree angle, and he marks the 16th fret at the body join. OOPS. 16 frets? It DOES work much better for the design of the top, but it would have been better to know that from the start!

I have to finish the video, and maybe some more if it doesn't click. I'm used to engineering drawings in the shop. Trying to find how tall a tuner is, they never give the dimensions I want. I know it will need a block under it. Something like 7/8" or so total. Videos to watch. Drawings to make.

The plastic Humbucker covers with the big hole hole might work just fine. I'm drawing everything up .8 scale, because that's the size paper I have. I still can't draw the head on, but that shouldn't throw any surprises.

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The belly is close I think. I goes from perfectly quartered to perfectly flat sawn in about an inch or two. It doesn't seem TOO flimsy. The tone hole being right at the block doesn't seem to be as much of a problem as further down. I will use parallel bars, but more like a vee arrangement with them close at the bottom. I think I'll check the deflection, but that is hard to do with a finished top: the edges move out! It is 167g and has tap tones of Dmaj. Low A string. D string, and F#. I don't know if that mean s anything, but that's what they are.

The back is roughed out on the inside. It is almost the same way I did a Montagnana violin. shallow diagonal arches, and cross arches, that are then made into double arches. In this way the outside arch will rise quickly. The center is flattened out some so it isn't pointy, and the center isn't 10mm thick! (It is on my cello!) The belly of many violins, and this arch-top is done with just the straight diagonals, and cross arches. How close you go to the edge changes the outside arch.

I like to go a little shallow, so I can see how the outside looks, and make it lower or higher.

I bought the wood to be a viola back a long time ago. Never did it.

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I worked on the outside the last couple afternoons. I used a 10, 8, 6, and 5mm Allen wrench to set the drill. It is still very thick, but now I have some idea of what the shape is, while still having a good underlying arch on the inside. It is about .75" high. That's how thick I told the guy to cut it, and he got it right on, all the way down.

The violin in the photo has a 19-20mm high arch. The same height. Even though the violin is way smaller, the arch on the guitar looks taller. I'll work on the outside to get it so that it just looks like it flows up, and you won't know it is so high. The violin does have the flatter long arch of a belly, so the top and bottom rise fast. The outline of the guitar is much fatter, so the result will be different.

The ribbon figure of the Padauk is like that of Sycamore, It can be a problem. I had to sharpen the plane blades. They started just gliding off the surface unless you pushed down hard. If your plane does that, you have to sharpen it. It should cut with just pushing, not pushing down.

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I pot a couple afternoons on the back. It is a back and forth thing between the inside and the outside. I don't finish the outside, and then thickness it. I do the arching from the inside, and the outside uses that as a guide. The "feel" is given by the thickness, that is brought by the internal arching, and the choice of arching on the outside. For bellies, the long arch on the outside follows what is on the inside. On backs, I always make them a radius. That gives a thicker center.

This inside arch is like the Montagnana violin. It has half arches the blend in the middle. So the middle will be thicker, and the bouts will be thinner. For this arch top, I'm making the back to be quite stiff. I don't want it to be dead, but to move but still be stiff. The thinner bouts and edges should do that. I'm thinking 2.7 to 8.1mm thick. The belly is, or will be something more like 3.2 - 4.8mm. I think. Different animals.

I figure out where the cross arches would be for a curtate cycloid. That is what you get taking a spirograph wheel, and rolling it down the straightedge. At the halfway point, the height of the arch will be half as high as at the middle. That point is not half the arch width. It is half plus the height of the arch. Higher arches stay higher longer. They also stay convex longer.

I don't always make perfect curtate cycloids, but they work well.

I use cross diagonals on arch top backs, and all bellies. These are split, and don't go all the way from end to end. I also have long arches on the inside that don't go all the way across. All the cross arches on the inside are perpendicular to the same at the edge. They are not just horizontal. It is easier to do than to explain.




The outside looks like a dome, but the long arch is an 800mm radius, and the cross arches are going into a cycloid. I have an 800, 900, 1100, and 1200 mm arch gauge made up for violins. The half way points are all about 1.5 mm high still. The edges are about that, and in-between it is thicker still.



This is what the cross arching looks like now.

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Watching with great interest!

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

The back is getting closer now. It is at the point now where I can only scrape; the grain fights back. I thought about starting on the neck. I have some mohagany, and maybe I'll use a piece of 1/4" something as a lamination. I don't.have a router, but a lamination can give me a ready made slot. Looking at SM I see an electric guitar uses an18" rod. That's way too long for this. Some of the end is up in the air! The other one I made had the 14 1/4" With the 16 fret neck that means it would be 1/2" away from the nut and the body join. The key head will still be past the nut.

Wil that work?

I use a gauge with a dial indicator for the thicknesses. Going from.The middle, the dial should.keep going down.

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I had to do some thinking. I rarely make the same thing over again, and even when I do, I re-engineer it. This is all new. A bolt on neck, that was a glue in. In line tuners, because I have a set. figuring out the neck angle, and how to fit a tunomatic on an arch top bridge. I'm still thinking about zero frets, and a way to have the strings float on the bridge.

Sketching is my way of thinking.

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On to the neck, and the faux humbucker.

1/4" lamination in the middle, and you don't have to cut the slot for the truss rod. So the center piece is cut, and thicknessed; mostly with a scraper. Now I have to be sure to cut the 3/8" slot in before I glue. You can see that happening, can't you?

The fake humbucker/tone hole, is ALSO a tornavoz! Why not. The stock I had was 40-45mm wide, so 20mm or more will be below the belly. It is mitered, with posts on the inside, rounded out. It is a lot easier to draw than to make. It isn't square, well one corner is! I might make a cover to hold on a piece of black cloth, or foam make it look like something solid, and not a hole. I could fudge that in. it is only the strings going across the top that would show the "uniqueness" of it.

I might need more tone hole area. I have it figured that the volume is somewhat less than the Stauffer guitar, and the tone hole is only half the area. So maybe to humbucker tone hole is 60% of what it should be to be equal to the Stauffer. I thought of smaller holes on the top, or a side port.

Does it need more area?

Any drawbacks to either sort of extra porting?

The box is Katalox, and the fretboard binding will be the same. I don't have long enough pieces for binding that I want to cut, or thin down, so I'll use some very thin black plastic binding that I have. Figured Bubinga, I think that's what it is, fretboard. It should look ok.

This morning I took the clamps off and I have the easiest truss rod slot I never cut.

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More on the neck. I drew the key like joint for the neck double size. Found that I cut the neck heel too far south; I thought I left everything long. The 16th fret will have to be 4 mm short of the body join. Don't tell anyone. I don't think they will care. It has a cutaway anyway.
I didn't want to try to chisel out a chalk fit joint, so I did it the easy way. chalk fit it, and then glue sides on. Once I'm sure about the length, I can glue the head on, and I should probably order fret wire, and the tunomatic. bridge. I don't think I need anything else. I'll get strings at the end, they usually come in a day.

Someone needs to tell this guy to put away his stuff as he goes along.

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Another design feature on the neck:

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Well, the neck joint is almost done. I made it way too complicated. That said. It should work well.

I have to add some at the bottom of the block by the heel of the neck. Something for the ribs to glue on to. I worked on the color palette too. Some stuff I had in the cabinet labeled oil ground. I have a small and large jar of it. I think it is oil, resin, and turpentine? I don't remember. I put a tiny bit on, and rub it till it's hot, wiping it off. Then the next day a drop of that and then a drop of varnish. Rub that off. Then a coat of Osmo. For the Bubinga Fretboard, I added some Azo green oil paint to the Osmo, and didn't do the oil stuff. It brought out yellow that you can't see.

Another color palette drying in the sun.

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I have the fretboard conical radius roughed out; about 7.25 - 12" because it works with a 14" rad at the bridge. I have to make a box to make cutting the slots easier. I planned on putting 2 more holes in the top, and it would still only be about 80% of what the little Stauffer, about the same size has. Cutting this hole, and turning the fake 3 way switch to fit the hole, it looks fine like that.

Maybe I'll do a small side port. do you put bracing on the inside of the ribs where you want the port to go, and then cut the port, and bind it after it is all together?

Another new technique.

I think I'll have two tone bars, almost like a vee, to keep the center where the strings are stable. The flexible sides should let it pump! The back will be fairly stiff.

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I cut the slots in the fretboard yesterday. I made up a miter box. A 2 X 4 cut wide, and planed to the 60mm I was going for. Take the cutoff, and slice that in half for sides. Glue them on so the sides are 2mm taller than the depth of the saw. Saw a straight, square cut.

I used masking tape to make it easier to see the pencil marks, and went over them with a caliper. I'm out of tape now!



when that was done, I finished off another fingerboard, a maple one that had a coat of iron acetate the day before. I put a superglue coat one. Hung in the garage, Sanded smooth, and put on a coat of Osmo.

I guess I really need to clean the CA dust from under the fingerboard.

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It is amazing how you don't see the dust until you take a picture of it. LOL

Looking good Ken, I will be interested to hear how a 13" arch top sounds.

Cheers,
Bob

I have my fretboard ready to glue on the neck. I need the truss rod first. It is in the mail, plus other stuff. I'll have to see where I'm going to put it. I had the thing drawn-out with a 14 fret neck, but now it is a 16 fret neck, so it is quite a bit longer!

I was checking how the tap tones are before I cut the big sound hole, and then add the bars. I have the bars ready to glue. I found that the belly is not far off from my cello belly! Here are the screenshots from audacity. The cello does have a bass bar, so it is easier to tap, and has overtones all over.





Sitka / HD cedar decking.

Still the cello is about twice as big, 415g to 169g.?

I wonder if it is a little too flimsy on the ensds. We'll see what it's like with The bars. A free plate is not The same as one that is glued on.

The cello peaks are a bit higher than the guitar's 100 150 200.

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I glued the fingerboard on the other day. I remembered to cut a little off the end of the carriage bolts, and put them in before gluing. The truss rod is before the nut, only the adjuster peeps through.

Now I have to flatten the fretboard, put some finish on it, and pound in frets.

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