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Woohoo! Finally time to start my first harp guitar, which is an instrument I've wanted since I first started building.

Here are the woods,
Soundboard: Redwood from David Maize
Back/sides: Local osage orange from Aaron Craig, with center wedge of Brazilian RW from Chris Cantwell on ebay
Neck and harp headstock: Butternut from Artisan Lumber
Fingerboard: Bois de rose from Gilmer
Bridge: Brazilian RW from Darren Hippner
Binding: Brazilian RW from Sniggly
Tuners: 4:1 Pegheds... may switch them to 16:1 if it's too touchy, but I like the 4:1's on my harp uke

The neck is fan fretted from 25.5" to 24.75". There are 7 harp strings, normally tuned to the E major or E minor scale. The longest is 36".

Inlay theme is Halloween, my favorite holiday. Osage orange is sort of orange like pumpkins and smells like hay bales and dried Indian corn in the fall, so I decided to run with it

I've been doodling up the plan for the past few days, and it's finally done, aside from possibly adding a headstock inlay depending on whether or not I use a certain BRW headplate that looks awesome on its own. The image is pretty huge, and includes notes of various dimensions incase anyone else wants to build one like it. But be aware that the harp strings are fairly tightly spaced. This is designed to fit my hand, so I can reach all 13 strings at once without too much of a stretch.


Time to start making wood chips

Ok, after some dawdling around debating whether to change the inlay designs and such, I decided to stick with the original plan.

First, the top. Plane the show face nice and smooth, coat in shellac, and figure where to join it using the offcuts from the body templates

I angled them out a bit to follow the grain lines. Still leaves room for a harp uke, as you can see. And two regular ukes as well, I think. Jointing was surprisingly painful, despite cutting out the two halves beforehand so the actual joining edge was no longer than normal. I think my wooden jointer plane is just a hair out of flat due to the humidity being insanely low.

Here's the wood pile, including the joined top:


Then on to the harp arm rosette. First cut a bunch of little pieces of spalted sycamore, which are white on one edge, dark in the middle, and gray on the other. Then edge glue them so the colors alternate. Glue the pattern on, and get cutting. Go a little bit on one side, then a little bit on the other, so you're never cutting on a long skinny thing... especially because this wood is pretty rotten and crumbly.

And done. This is actually the back side of it, so that little chipout doesn't matter.

Then score the soundhole. Fortunately redwood is soft enough to cut through entirely by knife, since my circle cutter can't go this small (the drill hole is just for reference). Tack the snake down with a few dots of elmer's, and score around it. When inlaying into softwoods, I first score with a scribe like normal, but then after popping the piece off, go back over the line with an x-acto knife to cut through the dark grain lines. Especially in redwood, the lines are way harder than the light wood, so the scribe doesn't really even mark them.

Route it out, and then install the tongue. I'm using a fun technique here, where you drill a hole, thread a jeweler's saw blade through it, and saw a fine line. Then squeeze veneer into it.

Or in this case, kids' construction paper It's not thick enough to tightly fill the slot, but looks good anyway. Normally I only like using natural materials, but I don't have any bloodwood veneer on hand, and even if I thinned some down manually, it wouldn't show up as well against the redwood. Then glue in the snake itself, level it down, glue in a couple bits of wood where the scraper chipped it (the white parts are pretty thoroughly rotten), and slop shellac around on it. It darkened more than I expected, but looks quite nice.

The tongue looks funny from the inside:

I was about to add a black MOP eye, but then I had a better idea... I found a paua dot that has a black line right through the middle, which will make a perfect slit pupil. However, I have to be very careful that it never gets any thinning or the line will move. So I'll install the eye at the very end, after I've done final scraping.

And now the progress on the main rosette. This design is deceptively difficult, which is one of the reasons I was thinking about scrapping it. The materials here are birdseye movingui for the thin vine, quilted sipo for the thick vine, and camatillo rosewood for the branch.

Cut out all the pieces, and then glue down the first round for scoring. This is the tricky one, getting everything aligned relatively close to the design.

Then the rest can be positioned relative to those score lines.

Then route all the vines, and glue and level the first batch.

Note that the pieces are longer than they need to be, not stopping right at the edge of where the second vine will be. That gives me a little leeway in the cutting and positioning, and then I can just run through them with the router to make way for the second vine.

The second vine is more tricky, because I do have to very carefully file the ends of the pieces to where they fit tightly against the first vine. But before gluing them in, I added some thorns to it. Take a little piece of rosewood veneer, sand the end to a sharp edge, cut it off, and split it into 2-4 thorns depending on how wide it is. Then jab an x-acto knife into the wood to make a notch, and press the thorn into it sideways by applying pressure to the endgrain of the thorn with a small flat surface like a screwdriver or a small chisel, while holding it from popping up out of the notch with a thumbnail.

I had two of them crumble under the pressure and the chisel scratch the wood... one really shallow that steamed and scraped out no problem, but the other shall remain a scar, that probably only I will really notice It's visible in the next picture, past the tip of the thorn above the branch. Just a little sideways scuffing of the grain.

Then another router pass to knock off the ends of any thorns I couldn't get jabbed in to their full length, glue and level the thin vine, and route for the big branch. Looks like I got the router set a little shallower than before... oh well. I love how you can layer wood inlays this way, rather than having to fit all the pieces precisely together like with shell.

Then level that, and finally I can route those wrap-around vines. Redwood is nice for super skinny things like the tips of these, which are too narrow for a 1/32" router bit. It's so soft and brittle you can just poke at it with a knife and clear them right out. Got a nice tight press fit on these.

And finally, add some green abalone leaves. All but one of these were made from tiny scraps left over from other instruments A pain to hold on to while cutting and sanding, but always good to conserve materials. I got the pockets for these a tiny bit too big and a tiny bit too deep, but they'll do. I decided to hold off on routing for that last leaf, because it will be very close to the pumpkin stem, and I want to make sure the positioning looks right.

Another tricky thing here is the camatillo rosewood immediately bordering the light colored sipo. Camatillo has intense color which bleeds like crazy when touched with shellac, so I had to very carefully wipe shellac on just the branch, and then again with a fresh paper towel just around the branch, because even after it's sealed, passing over it is risky.

Next up, the pumpkin. If I'm cool, I'll do the eyes and mouth in African blackwood. If not, I'll just saw them and fill with black epoxy.

Very cool Dennis. You certainly have a knack for inlay. I just don't have the patience for that detailed stuff. I get carried away and then frustrated and start snapping all my inlays in half.

Well, my faithful readers, I've worked myself into a state of indecision with this pumpkin inlay...

First of all, I made the pumpkin. I figure if this guitar is already border-bound by its Brazilian rosewood, I may as well use a tidbit of pernambuco too. Kind of silly, but I cut out the pumpkin shape, then sliced it into pieces, filed the saw marks out, and glued them back together The whole point being to add glue lines as visual representation of the rumples. Stem is (I think) black limba.

I was initially planning to burn shade them by dipping in hot sand, but I don't have any sand, and it would be a pain to heat and practice anyway, and looks fine as is.

Now the problem... see, first I was thinking the face needed to be filled in with something black, either wood or epoxy. Then it occurred to me, it would be even cooler (and easy) if I cut the face out, inlay the pumpkin, and then inlay a piece of black MOP from the back side so it shows through, but the face still has some depth to it. Then I was testing pieces, and ended up deciding on gold MOP instead, to be more like a candle inside of it.

Then I actually went to inlay the gold MOP, and it occurred to me, why fill it at all? I could leave it as an actual window into the soundbox. And on top of that, the gold MOP looks a little too white once everything is actually together. But, leaving it open will be much more fragile. I beat on it a little and it feels solid (not to mention it survived the face sawing process in the first place), but it's still small and thin pieces of wood held together only by edge joints, with the glue lines made a little thick on purpose so they show up better. However, it will be somewhat protected by the strings most of the time.

So, what do you all think, gold MOP,

Or open?


Here's how it looks from the inside. If I leave it open, I'll at least build up the bottom/right edge of the pocket with hide glue to boost the strength a bit.

. Wow

Open. It stands out more, with the dark features.

Ed

I also agree that you should leave it open.

It looks great open, but if you are worried about strength, you could always back it with ebony.

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How about some black MOP? Select a darker piece, and you've still got a tiny bit of 'flash' there.

+1 I like this idea

Ok, so I decided to leave it open, and after a bit of drama, it's all good and done.

Drama stage 1, the day after first installing it, I woke up to this:

I'm not sure exactly why, but one of the glue lines decided to let go. Perhaps moisture related. So, I got on to cutting the backing veneer, which took many tries due to cracking off the tips of the triangles. Then I realized I could just route the pocket to a more rounded shape

Drama stage 2, I went to glue the veneer on, but whaddya know, it's just a hair too big. That's what I get for not pushing it in all the way for the test fitting. It's too flexible to force, so I had to shave on it some more... and of course by then, the hide glue had gelled up. I had to clean the glue with water, and reheat it for the next attempt... which of course risks separating all the other glue. But it held together, and I got it glued on and pressed flat. Didn't even have to re-level the show face.

Gave it a full day to dry this time, and then used small chisels and gouges to carefully carve through the veneer like such:

The strip going across under the eyes is pretty thin, but should be enough to hold it.

Then cleaned up the remaining bits of glue in the teeth, cut out the soundhole, and finally the rosette is complete:


Next up, the neck and bracing. I keep hesitating on cutting the neck, thinking I'm going to screw up the heel-to-headstock length due to the fan fret angle. I'm also debating whether to do two carbon fiber bars and an adjustable truss rod, just the two CF bars, or a single CF bar. I kind of don't like adjustable truss rods... heavy, potential to rattle, and never seem to help when I have relief problems anyway. I level my fingerboards after gluing to the neck, so I can sand in any relief I want at that point. And not using an ebony fingerboard, the neck shouldn't bow too much with humidity change. But I do like the truss rod cover as a visual element of the headstock And the rarity of non-adjustable steel string necks makes me wary.

I'll glue the neck to the soundboard before doing the bracing, so I can be sure the fans will pass between bridge pins. I was tempted to do redwood bracing... I have an instinct to match it with the soundboard wood, but ~350lbs of tension on brittle redwood braces doesn't seem like such a good idea, so I decided to split and plane a pile of brace blanks from some free sitka that came in an order from Fraser Valley:

Sadly, like every other 1x2" bracewood billet I've ever bought, it had horrible runout. Couldn't get any long pieces that are tall enough for the X. Oh well, can't complain too much about free wood. May use some lutz, or I think I have another sitka hunk from Alaska Specialty Woods to try... although it's much nicer if all the braces are from the same piece so you can gauge stiffness visually.

Back to my staring contest with the neck blank.

Dennis - I'm loving this thread! Your skills, craftsmanship, and imagination are wonderful! I'm hoping to learn a few things from you along the way.

Alex

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Just found this thread. Dennis, you are crazy good!

Dennis,
Those inlays are crazy tight! Congrats. Can you post a pic of your inlay set up?

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Thanks guys

Sure. It's nothing fancy... and particularly I've been meaning to make a new cutting table for ages, because this thing is the most pitiful excuse for a tool ever made. All warped and springy, which often results in edges of pieces not being perfectly vertical, so I have to file on them some. And the cutting notches aren't even really useful due to the lack of flatness.

Here's the full list:
-Jeweler's saw from LMI.

-Feather weight fret saw from Lee Valley for cutting from larger pieces.

-I'm not sure what size my blades are, but they're a lot finer than what LMI sells.

-Extra extra coarse dia-sharp stone for flattening and thinning shell pieces, and smoothing out saw marks on convex edges (sandpaper works, but since I have this for sharpening I may as well use it here too).

-Half round and knife style needle files, mainly used for smoothing out saw marks, and fitting pieces to eachother.

-Scribe from StewMac. It's just a pointy piece of metal, so you could sharpen a nail or something to save money. But it makes a huge difference compared to scoring with an x-acto knife, since you can get right up on the edge of the piece.

-X-acto knife, for cutting sharp corners in pockets, and to cut through the hard grain lines in softwoods after scoring with the scribe, for better visibility and cleaner routing.

-Black&Decker Dremel style tool with StewMac router base.

-Three bits, 1/8", 1/16", and 1/32". I'd like to have a 1/64" too. The tape on them acts like a fan to blow away wood chips.

-Forgot to include in the shot, but a card scraper for leveling. Makes nice little dust piles instead of fluffing it all over, plus you can see exactly what you're doing, unlike using a sanding block. I also use various planes and chisels for taking down wood inlays that are significantly too thick, but always finalize by scraper.

When cutting shell, I keep everything soaked with water to contain the dust. Better than a large and noisy vacuum, except that you can't use paper patterns glued to the pieces... I usually draw them on in pencil, although it's a bit inaccurate copying by eye instead of tracing. But even tracing like I do for wood inlays is less precise than computerized copying. Most of the stuff I do doesn't need that level of precision.

I'd originally planned to set up an automatic water dripping system for shell cutting, which the groove routed in the table would drain into a pan underneath... but it turned out to work fine just dipping my fingers in a bowl of water frequently, and put a paper towel underneath to soak up most of the drips.

So that's about it. Basic tools, lots of fiddly work, roll with the punches. If I were to do the same pattern more than once, it would be a bit different every time. I got pretty close to identical on my Sun and Moon guitar, but there are still some small differences in the manes, tails, heads, etc.

As for this harp guitar... I've been slowpoking along for the past week, but I'll post a proper progress report soon.

Thanks Dennis! Where do you buy your bits?

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http://www.precisebits.com
I need to order some more actually... my 1/16" bit is getting a little dull, and is the one I use for most things. Who knows how many square miles of wood I've chopped up with it by now And this time I can actually get downcuts. I didn't realize until fairly recently that I'd been using upcut bits all along

The depth ring on them is quite handy when switching bits, to avoid having to readjust the depth all the time. They're not exactly equal, but very close. And there's a handy trick I've found for fine depth adjustments without having to fiddle with the thumb screws... just turn the dremel in the router base a little bit.

I've really fallen off the horse with keeping this thread updated... and the build itself too. I've still been making a point to do some little thing to it every day though, so I do have some progress to report, and getting back in the swing of things these past few days so hopefully I can still get it done before spring humidity arrives.

First I wanted to do bracing, but then I needed to get the neck done so I can make sure the fan braces pass between bridge pins, but in order to get the markings on the neck blank just right (particularly the nut angle) I had to do the fingerboard...

I decided to use this cool figured granadillo board, rather than the bois de rose. Looks pretty ghostly

Carefully align the guide block with the marks, using my not-so-reliable little LED flashlight, because my main lights aren't bright enough.

The marks are tiny little pin holes, not really visible at this resolution. 3 sets, 25.5" scale marks follow the low E string's path, 24.75" scale marks follow the high E string, and 25.125" scale marks along the centerline for double checking. Once I get the block in place, I stick a cam clamp on it, re-check that it's right at the marks, and gently hold the saw against it while cutting.

Then glue on the binding:

And finally I can get busy on the neck. This was quite a pain, as the blank was 2" thick, so I had to rip cut it from the end to the heel. I need to get a proper saw for doing that. My ryoba seems to be a tiny bit bent or something because the cut always twists gradually. Had to use my cross cutting saw, which takes forever.

Then cut the scarf while it's still close to 1" thick, thin down the shaft part so it tapers from 3/4" at the heel to 5/8" at the nut, and glue on the scarf piece:

That leaves enough thickness on the headstock to plane a tilt into it for the angled nut.

Then I had to figure out headstock woods... I'd planned on doing a cool effect on the harp headstock using cross grain black walnut with sapwood, to create a sort of evening sky gradient with light horizon, and then that big tree inlay on top of it. Unfortunately I couldn't find a good piece of walnut for it. However, I did remember a cool looking chunk of osage I saw lying on the ground while hiking last spring (I've regretted not picking that thing up ever since). So I went in search of it, and luckily it was still right where I last saw it, and fairly dry by now

It has some extreme curl, but also a lot of cracks. So, I went to work, again making long rip cuts with my cross cutting saw

Gorgeous Super glued a few cracks, and it's good to go.

Cut out the headplates, glued the harp one onto the offcut of that double thick neck blank, cut out the harp headstock, and two more slices for a stacked heel on it. Crescent shaped to reduce weight.

Then some rasp work to refine the shape:

Next up is drilling/reaming the tuner holes, which must be done before gluing on the heel because the reamer handle would run into the heel on the first string. And then get back to that long awaited neck.

Hi Dennis,

I am following this thread with great interest. It is looking fantastic already.

I have a question. Will there be a radius on the sound board and back? If so, how will you go about doing it, as you would need a very large radius dish. Would you only put a radius on the lower bout? Am very curious as i would like to build one of these some day.

Thanks for your help.

Ed

I'd initially planned on a radius, but I'm leaning toward flat now. Might let it vibrate a little more freely at the ultra-low frequencies needed for this instrument, plus I'm going to make the string-height-at-bridge more like 0.375-0.4 rather than the usual 1/2". With so many strings on it, 1/2" would probably over-torque the top and require excessive bracing, and since I usually use the radius to tilt the neck back and gain about .1-.125" of height at the bridge location, the geometry should work out just right with it flat.

But either way, the harp arm doesn't need to be involved in the radius, so you could use a regular dish for gluing the braces. I use the method shown in the Cumpiano book, planing a radius into the braces and springing the top onto them with cam clamps. Also could make a monster solera, which would be helpful while assembling to support the edge of the top while you glue dentellones.

Continuing on, drill the tuner holes and then ream them out... maybe should have gone a couple drill sizes larger before reaming to save some wrist fatigue. These geared pegs are quite large.

Then do some carving on the back while I have an easy run on it without the heel in the way.

And after gluing the heel on, lots more carving. More difficult, working endgrain and concave surfaces all over. Had to sharpen up all my tools. Still needs sanding. 150 grams currently... a little heavier than I was hoping to get down to, but not terrible.

Then plow plane the truss rod slot.

And glue in the spline with light clamping pressure. I hate epoxy.

Tomorrow I'll level the spline, and plane two more slots for the carbon fiber bars. There is a small concern with this design... integral neck style normally involves chiseling a ledge into the headblock portion of the neck, so it's flush with the soundboard surface after being glued to it. But all these reinforcements aren't down deep enough in the neck to cut the ledge above them. Maybe I should have waited until right before gluing the fingerboard to install anything, so I could just cut slots through the soundboard. Now I'll have to do some funky routing.

How long does it take you to complete a project like this?

I'll let you know when it's done Probably another two months or so. I may be running into humidity troubles here soon though...

Got the harp headstock all sanded and shellacked. Smooth and shiny, and down to 143 grams now after carving away some of the ridge along the front edge, and hollowing out the inside part some more. Walls on the heel are still maybe 1/2" thick, so I could probably do a little more, but being endgrain I don't want to weaken it too much.

Then cut the carbon fiber slots. The bass side slot tilts down a bit past the nut due to me not paying attention to where I was putting pressure on the plane, so the bottom of the bar won't make contact there... shouldn't cause any trouble though, and the epoxy should fill it somewhat. The shavings will make nice fine line purflings for something Tempting to use them along with a dark layer as side/back purfs on this, but I'll probably stick with my original plan of a single curly maple veneer line around the top, and nothing more. I kind of like the minimalist style on not-so-artistic elements like purfling.

Cutting the CF was messy. I used a dremel cutoff wheel, with a little squeeze bottle of water to drip on it to contain most of the dust... which of course meant black droplets sprayed everywhere. I think I'll do that outside next time. Then a little sanding on wet/dry paper to smooth the edges and refine the angle, and glue 'em in. Fortunately I had the sense to run masking tape just outside the slots, to keep the fingerboard gluing surface clean. No clamps, just push 'em down in there and leave overnight.

Then cut the heel block for the neck. I just roughed it out with a few straight cuts, since I can get too accurate in 2" thick wood with a coping saw. Flatten the surface on my trusty extra-extra-coarse diamond stone, and glue 'er down.

And to save time, glue down the headplate at the same time. Clamps everywhere You can see how microscopic my shop is in this shot. Wood tower on the right, tools on the left, chemicals in the corner, saws and diamond stones are on the floor behind the bench.

Then saw the neck taper and rough cut the headstock shape.

And make some funky angled cuts on the heel to save carving time.

And that's it for now. Next up is sawing the slots for the sides to go into, carving the heel, refining the headstock shape, drilling the tuner holes, thinning the headstock, carving the neck, and cutting the ledge in the headblock portion. Then I can finally glue the neck to the soundboard, thereby finalizing the bridge location, so I can make sure the fan braces go between bridge pins. There's headstock inlay work to be done as well, but that can wait until near the end. I want to get it braced and boxed ASAP for humidity reasons.

Starting to look more like an instrument. You do wonderful work, very clean, very nice. I like your shop its not too much bigger than mine. I use my work office, which no longer gets real work done in it anymore. I use my desk as a workbench

Keep it up, ill be watching for more

Whoa, I thought I had the smallest shop ever Then again, I do have that open floor space off to the side of the bench now, where I can sit to do gentle carving work. Most of the time I sit on the bench though, where I can hold things with my feet, and push as hard as I want without the bench going anywhere. I would like to have a high surface for shell cutting and inlay routing, but for general woodworking I love this setup.

Continuing on with the neck, mark the slots for the sides to slip into. They need to be angled both the same, so even if the heel is narrower than the fingerboard, the sides will look like they pass right through it. The geometry on this instrument works out nice and easy, with the top being braced flat, and no neck angle, so the slots are just 90 degrees to the fingerboard glue surface. I start by chiseling along the marks, to give the saw a place to grip while I get the cut started.

Saw freehand, then stick a scraper in the cut and saw again, holding the saw against it to widen the slot.

They're pretty much perfect on the top, but a little off on the bottom... i.e. not quite 90 degrees to the top surface. But at least they're both off by the same amount, so they still match nicely.

Lots of carving on the heel and neck-to-headstock transition, and spokeshave to connect the two.

Then thin down the headstock, which was a lot over-thick, to provide material for the handstop lip. I wish I could find a cheaper source of butternut. Light weight, carves easily, and the color is beautiful. This was a lot of fun, effortlessly peeling up giant chips with my trusty gouge. I've been using it a lot lately.

One unfortunate thing is that I forgot to closely inspect the sides of the neck blank before laying out the pattern, and failed to notice a rather poorly placed pin knot...

I don't think it will cause any strength/stability issues, but it's kind of ugly. Oh well, at least I have no plans of selling this, and I don't particularly mind it. Certainly not worth scrapping the entire neck over.

Here's a profile shot of the heel, from the harp arm side. I may carve on it a bit more... looks a bit too bumped outward in this shot. Plus I could go a little lower profile on the heel-to-neck transition, which I like to do on cutaway instruments since it allows keeping your thumb on the back of the neck at higher frets.

And a shot from the top, with the headplate thinned down to final thickness and shellacked to show the lovely curl. I think I'll add rosewood binding to really frame it up, although I will have to do that before gluing it to the soundboard since it would be a little tricky cutting the channel while the harp arm is so close to the side of it. Debating whether to do my standard tree inlay, or logo only... it's so pretty like it is, but the tree would look good and Halloween-ish too, and it'll have to have a truss rod cover regardless.