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Humidity is still too high for assembly, but it should be dropping soon, so I've been back working on this.

Continuing on with the neck, my next objective is the headstock. I didn't get any pictures of the headplate, but there's not much to it anyway. Scrape one side flat, sand an angle at one end to be the nut edge, glue it on (make sure to put water on the outer face to counter the expansion from the glue, so it doesn't curl up at the edges), and then plane/scrape/sand to thickness. Could thickness before gluing, but it's easier when it's on the neck.

I use a paper template to draw the outline of the headstock, and poke holes for the tuners. Then drill them with a brad point bit. Use a square to check for vertical frequently. Not quite as accurate as a drill press, but close enough. A little tilted in this photo since I'm not holding the drill. Note that the headstock is still over-thick. I'm not really drilling all the way through and into the bench

Then Jeweler's saw for the crest. Not particularly accurate in such thick wood, so I keep my distance from the line.


Then some chisel carving to get closer, and lots of fiddly file work to refine it. Chisel the sides close to the line as well, and rasp/file/scrape to refine. This is another place that it's nice to have some excess thickness, so I don't have to worry about chipping out the back edge.

And finally, it's time for that comet inlay. I found some good ripples around a knot on a walnut board that I bought for making heels.

Saw off a slice, cut the gold MOP piece, and route a pocket for it.

Glue that in, cut out the overall shape, and score around it on the headstock. When working with dark colored woods, you can rub a little chalk in the score mark to make it easier to see.

I also decided to add some stars up here, so I drilled a few holes. Routed for the logo inlay as well.

...and that's as many photos as I can upload in one post. More tomorrow.

After gluing all the inlays, it's time for headstock binding. Score with gramil and some freehand knife work, and chisel it out.

Then the strips, which have curly maple veneer glued on as side purflings to match with the fingerboard. No need for fancy clamping methods. Just get hide glue everywhere and rub them flat with your fingers, and they'll stick just fine. Amazingly tolerant to the heat and water of bending, too. No delaminations.

That one strip was stubborn and wouldn't bend straight, so it was a pain to glue to the headstock. I did it in two sections, holding it by hand while it dried. The third strip is just slightly curved, to cut the pieces for the little point at the top center.

Then the squiggly crest pieces, which are too tight to bend, so I saw them from flat stock and file to fit. Cutting the veneer was actually the toughest part, because it's so brittle. Probably should have glued the purpleheart to the veneer first, and then cut the veneer. The bent veneers are just tossed in the glue pot for a while and then force bent.

The miters didn't come out quite perfect, but I'm not picky enough to redo anything for minor visual flaws.

Then chisel/file/scrape the bindings level to the sides of the headstock, and scrape the bindings and inlays level on the face. More filing and scraping to round the bindings over, micromesh pads to polish, and shellac.

Closeup of the comet inlay to show the ripples in the wood. Just what I was looking for

Then finish carving the neck with knife/spokeshave/rasp/file/scraper. Here you can see the long pores exposed, which means the grain is nicely aligned with the neck, and feels nice with an open pored shellac finish.

Carve the back of the headstock with a large gouge, tiny plane, and flexible scraper. Sand, shellac, fine sand, more shellac.


Just a little bit more work to do on the neck, and then it's on to waiting for the humidity to go down 60% and raining right now.

Next up is the truss rod. Hack saw to length, clamp in vise, thread one end with a thread cutting die, bend the other end with propane torch and hammer (really easy, steel doesn't conduct heat very fast so you can hold it in your bare hand, heat up the spot where you want the bend, place the hot spot at the edge of a brick, and tap the end with a hammer to bend it down), then polish it up (probably not really necessary, but I figure it might reduce friction so it can slide more easily in the neck and distribute the tension on it evenly).

Unfortunately I didn't take photos of any of that. But here's the end result of the bent anchor end, and the hole into the heel that it will occupy. Notice that I chiseled a little curve down into the hole since the bend isn't a sharp corner. This anchor is probably quite a bit longer than necessary, but I suppose a few extra grams isn't much of an issue at this location.

Then carefully glue a wood strip in over it, without gluing the strip to the rod. Gentle pressure on the clamps. Just enough to press the rod and strip into the curvature of the bottom of the slot.

And then chisel/plane/scrape down the strip level with the neck. Here's the adjustment nut access area, which I actually carved into the neck before gluing the headplate on, and then carved through the headplate before installing the truss rod.

And since I often never get around to making a truss rod cover once a guitar is finished, I decided to do it early this time. Slice the offcut from the fingerboard in two:

Scrape/sand to thickness, plane/sand to shape, polish it up, coat with shellac. I think the bois de rose looks really nice against African blackwood. Not an exact wood match so it doesn't look like I'm trying and failing to make the cover invisible, but dark enough that it doesn't interfere with the comet scene. Plus the hue matches the binding

And last thing for the neck, the pockets in the headblock portion to join it to the soundbox. Score with knife, square to the top surface:

Alternate between chiseling and scoring to dig it down without any chipping. Scrape out the chisel marks, and this is where the cutaway will glue into.

Then dig out the top surface for the soundboard to glue to, with a combination of chisel and dremel router. Couple router slips, but that won't hurt anything. Also trimmed the soundboard to fit to it.

And that's all for now. Though I suppose I could prepare brace blanks and dentellones while I wait for low humidity.

Lots more progress! Humidity has been good for the past few weeks, so I've been too busy actually working on this and my other in-progress instruments to bother updating the threads.

I also forgot to take pictures of the soundboard bracing. First step is to glue the neck to the soundboard, which is just a matter of sticking it on and pressing it down on the bench. Side-to-side alignment with the soundboard centerline is done beforehand by matching the end of the soundboard to the pocket on the neck, as seen in the last photo of the previous post (clamp it on dry, check with a straightedge, shave accordingly, repeat). Braces are glued using cam clamps like the Cumpiano book. The upper transverse brace is simultaneously butt joint glued to the headblock extension part of the neck... which is an endgrain joint, so I pre-coat that with hide glue and let it dry before doing the real glue-up.

I actually bent the sides a month ago, so you can also see the harp ukulele case I'm working on in the background Still need to find latches and a handle for it, and get all the padding anchored in there some whichaway...

This wood bends like butter, and is super stable too. Only a couple small touch ups after sitting around in fluctuating humidity for a month.

Make tail block (rounded on the back with block plane and sandpaper until it looks about right, and rounded on the front as well so the glue ends are just a little wider than the linings) and glue one of the sides to it. A matched caul would be preferable, but just sticking 3 cam clamps on it works too, and allows me to align things better since I can see if it tries to slide around.

While that dries, I can work on the cutaway miter. I really should properly photo document this next time... basically the process is to hold each side piece in place on the soundboard and mark where they lay, to find where the cutaway tip will be. Use that to mark on the side pieces how long they should be. Use a square to extend that mark across the piece. Saw a bit past the line, and then sand the miter right to it. The miter angle is eyeballed, but can be assisted by using shims like this neck blank under the tail end of the side while sanding.

The cutaway corner block is also eyeballed on sandpaper. I first glue it to the short side, and then glue that whole unit to the long side, using tape to keep it aligned and apply clamping pressure. Make sure to soften the sharp ends or they'll cut the tape!

I just held this one by hand while the glue dried, but on one of my other in-progress guitars, I discovered a way to use cam clamps on it by making the corner block square instead of triangular. It can be carved down afterward.

Going a bit out of order here, you can see the short side with corner block, and more tail block gluing. I use 3 strips of tape for alignment at the tail seam as well.


I never did get around to making dentellones before, so a minor delay doing that... saw, sand, split. Saw, sand, split. It's kind of fun and relaxing, actually.


Then it's on to assembly! Sand the end of the non-cutaway side until it fits in the heel slot, and glue that. No clamping necessary. The cutaway side does need clamped, but I haven't yet figured a good way to do it (whenever I do, it will probably involve 3 strips of tape ), so I just held it by hand. After that's dry, squeeze some glue under the tail block and cutaway corner and clamp those down, and it's dentellone time!


The cutaway to headblock transition came out great. Still a bit of scraping and sanding to get it fully smooth, but the seam is nice and tight, so no need for binding there (or on the cutaway tip), which will keep it looking nice and clean with the unbound back.

Going to be a fantastic guitar!

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

Love the headstock design!

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wah
Wah-wah-wah-wah
Wah

Reeeeeally nice work Dennis! I's funny that our wood choices for the top/back & sides are the same on our current builds for materials that are not very common. I'm thinking that my next one will be Dalb. Cultrata/Adirondack unless I really like the sound of the sinker redwood- I may use it again. This is the first time I've built with sinker, what do you think of it so far? I haven't braced it yet so I don't know how the tap will really be. Other than how easily it cracks I really like it. I started mine in October 2014 but haven't had a shop since November 2014 until this past month. I'm looking forward to being around more and seeing how this turns out for you. Looks great man!!!

Redwood in general is highly variable, and sinker even more so. This particular set seems a little dull in the tap tone department, so I have been second guessing my decision to use it for the minimalist bracing experiment... but on the other hand, the back is super lively, so it might work out to be a good balance. I'll probably do another with this bracing pattern, using a ridiculously lively cedar top from Alan Edie when he had that big sale in the classifieds a while back. Wish I would have bought more of those...

This set seems pretty strong across the grain compared to most redwood. It's also surprisingly lightweight, given the darkness of the mineral staining. The hardness and stiffness seems to suggest that it wasn't just an ultra-low density piece before sinking, so I guess the mineral content just doesn't add much weight. Thickness ranges about .150" in the center to .110" at the edges of the active area, and thicker in the upper bout. Weight is 172 grams unbraced, 202 grams braced. The open-backed box tap is still very high and tight sounding. Braces will need more shaving, and probably a bit of perimeter thinning too.

I'm not quite sure yet what I'll be pairing with D.cultrata next. I do have an excellent adi top from Aaron Hix, so I could do that combo too. But really I think just about anything would be good with a back wood this lively Seems very much like Brazilian in terms of stiffness to weight ratio.

Continuing on, here's a shot of the upper bout with the dentellones in, but no side braces just yet. Two of them will connect the upper transverse brace to the back's first brace, acting to prevent the brace ends from peeling up in low humidity, and hopefully making a stronger structure too.

Then trim the soundboard overhang. Always a bit nerve wracking since it's so easy to slip and scratch either the soundboard or sides. I use a chisel for most of it, and block plane for the endgrain around the tail. But redwood is really soft, so it went easily and without incident. And thus, the final shape is revealed

Very well proportioned to my eye. It actually came out 1/4" shorter than the design length of 19". The one thing that bothers me is that the waist ended up about 1/8" higher than intended. I love the look of a 12 fret with the waist centered precisely at the soundhole. I'll have to bring this one around to people when it's done and get opinions on the feel of it, since it does alter your playing position a bit compared to most guitars which have a lower waist. Going by my harp guitar, which has the waist even a little higher, it makes classical position a bit more comfortable, and right leg position a bit less comfortable.

Next step, chisel/plane the rim level, using the bench top as a reference surface and a flashlight shining under the edge to see where the high and low spots are. Then I can adjust the side brace lengths before gluing them in, which is easier than trying to chisel them down later. Gluing them is always a pain. I can only do 2 or 3 at a time due to the cam clamp bars running together. Definite disadvantage of my freeform assembly style. I know some people don't use side braces at all, but I feel safer with them.

And then the back linings. I decided to go with walnut side braces and linings just for appearance so the interior is more of a dark space. Last time I made my own reverse kerf linings, I told myself never to do it again. But they just look so much nicer, I did it anyway... and regretted it again. Such a fine line between flexible and cut through Ended up leaving a couple of seams between broken strips, which may defeat the purpose of looking nicer anyway.

Carve the side braces to look a little nicer. Chisel for most of it, knife to carve upward from the soundboard to trim away the shavings.

Plane down the linings, sand the rim to smooth out any inconsistencies from the plane leveling, and this guitar has officially reached the open backed box stage

And after that comes... the back. Plane and scrape to thickness:

Steam out dents that inevitably happen, using wet paper towel bits and the bottom of a pan of boiling water as a heat source. Re-scrape and shellac the show face. Use the box to mark the exact shape on the back and trim to just a bit oversize.

I love that fret saw (not to be confused with a fret slot saw). Sort of like a handheld jigsaw I use spiral blades for this so I can cut in any direction, and angle the saw so there's as much wood in contact with the blade as possible. Smoother cutting and no chipping. And I can work on a padded surface for this so no more dents.

Next up will be the back bracing.

I've been dragging a bit lately, but still making progress. Here is the long awaited back bracing, which I actually did shortly after the last update. First of all, prepare the brace blanks and radius them (block plane and a bit of sanding). Then fit them to the lining pockets, carving the ends down until they're just flush with the lining surface. Easier to do this before gluing them to the back.

Then stick a bunch of tape bits on them, like so:

And press the back down onto them. Pull it up, and voila, braces all nicely positioned. This back actually wants to be more radiused than the braces

Stick some strips of tape alongside the ends to mark their locations.

Then pull them off and glue them down one at a time.

Unfortunately, since the time of those photos, the humidity dropped a lot and the back turned concave and got stuck that way, even though the humidity is currently back around where it was when I braced it Perhaps due to the hysteresis effect. Going from high humidity to medium, the wood retains more moisture than it does when going from low to medium. But my hygrometer is wood, so it should be subject to the same effect, so it's still puzzling. But I guess I'll have to chisel them off and redo it

In the meantime, i was debating what kind of tuners to use on this one, and decided to try Gotoh 510 minis, which are surprisingly lightweight for closed gears. About the same as Sta-Tites, and easier to swap out the buttons for wood ones, which gets the weight down to about 170g for the set. StewMac's Golden Age Restoration tuners are even lighter at 130g, so I'm giving them a try too on one of my other guitars.

For the buttons, I decided to go with persimmon crescent moons in keeping with the space theme I have an awesome back set from RC Tonewoods, which had enough room to nibble from the corner.

Note that the centerlines are actually scored with a knife, using a square to make sure they're nicely perpendicular to the edge (which is planed smooth and square). The hole needs to be nice and perpendicular to the surface where it pushes against the washers on the tuner. After cutting them all out, I clamp the halves together and drill with a brad point bit, which follows the guide. Then chisel a rectangular pocket in the two halves to grip the post of the tuner, and glue 'em together. Unfortunately I forgot to take a picture of one while they were still open.

Then file the edges smooth, using this handy hunk of metal to provide clearance and squareness reference for the file.

Before and after filing. You can see the hole here, rectangular on the post side and round on the screw side.

Then a bit of chisel work to taper the thickness down at the ends, and coarse sandpaper to smoothly round them over. and round the edges. Lots of fine sanding, shellac, and micromesh to polish them up, and they're all done. More work than I expected, but worth it

Wow, I wouldn't have guessed that two thicknesses of a back cutoff would be enough for tuner buttons. About 3/16"? Will have to appropriate that!


Sent from my iPhone using Tapatalk

Thanks for posting more on your progress. I'm really looking forward to seeing it when it's complete. That's a cool technique for fitting the braces to the rims before gluing them to the back. Those buttons are a great idea and thanks for showing how you made them.

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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

Time to make the bridge! Step 1, drill the holes for the pins and route the saddle slot, using a jig made out of cam clamps and a neck blank.

I do it in several passes with a 1/16" bit. Go left to right, then add a 1/16" shim and go right to left, increase depth and repeat. The weak bearing on this tool drags to the side a bit, and this order makes sure it always drags toward the inside of the slot.

Then plane/scrape from the back side, tapering the thickness it toward the back edge. This tilts the slot and pin holes backward a few degrees. I also dish it a bit here, so there will be less sanding needed when fitting it to the domed soundboard later.

Scribe around the paper pattern, and rub chalk on it for visibility.

Saw straight lines to get close, and then chisel the edges of the bridge to get almost to the final shape.

File to smooth out the chisel marks, and scrape to smooth out the file marks.

Then back to the chisel to do the top side profiling.

File/scrape again, and it's done


I was debating whether to finish first and then glue, or rub joint it and finish around the bridge. I ended up deciding to do some perimeter thinning, which involved scraping most of the shellac off anyway. And with the bridge being a nice smooth shape, it shouldn't be a problem to French polish around it, so I went ahead and removed all the shellac for the rub joint.

Here's a shot of the plane marks from thinning, before scraping it all smooth.

Next up will be gluing the bridge.

Space is the place...beautiful work!

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

Things are moving along on this one. Currently in the middle of binding, which should be done tomorrow. But first, here are the pictures from gluing the bridge.

First, get it in place. I use an iGaging straightedge with 1/64" graduations, placed along the high and low string paths, and measure the distance from the 12th fret to the saddle slot (since the nut end is shortened for nut compensation). The horizontal position of the bridge is done by positioning the pin holes under the straightedge. I got lucky on this one, and the pointy ends of the bridge happen to fall on exactly the same grain line in each half of the top

Truthfully, the thing I've gotten the most use out of from the Gore/Gilet book is the little table of compensation values. Sure I could build the testing rig and find them myself, but I'd need to try a bunch of different strings and average them to get a good all-purpose location for the bridge, where the compensation can be fiddled forward or back for particular string sets.

The tape bits are for visual reference when rub jointing the bridge. They're not quite touching the edges, so there's room to move it back and forth a small amount to get the last bit of glue worked out from under it.

All went perfectly according to plan. Warm it up, apply glue, rub in place until stuck, then hold down the tips for a couple minutes (with a hand underneath for support) to make sure they stay good and tight. Then clean up the excess glue with wet paper towels (but not too wet because this is bare redwood, which will stain if it gets fully soaked).

And after it's fully dry, I can get the top shellacked again to make sure it stays clean. Then drill the bridge pin holes all the way through... which reveals a problem. Somehow I got the bridge plate glued a little too far back. I'm not sure how it happened, but I'm glad I glued the bridge before closing the box, so it's easy to chisel it out and glue in a new one. Or so I thought... purpleheart is so much tougher than the redwood, it kept pulling up chunks instead of cutting. I suppose I should have sharpened my chisel first

I'm pretty sure instrument repair is not my calling. Every time I have to remove a piece, bad things happen. But it's not the end of the world. Some top offcut material, and a bit of knife, chisel and scraper work...

...and it's back level. But I do need a larger plate this time to bridge the seams. I have some Madagascar rosewood bridge plate blanks from LMI that are about the right width, so that's what I used. The tape bits show where the front and back edges are. More than enough for the seams, but I figure if I'm going for a wide bridge plate anyway, I might as well get the extra benefit of stiffening the area behind the bridge to reduce peeling stress on the bridge joint.

Glue 'er down (rub jointed and held by hand because the bridge on the other side gets in the way of any regular clamping methods), and drill the holes through again. Much better.

Hopefully this bridge plate will last for the life of the instrument, because any future repairman trying to remove it may get the redwood patch along with it

On to one of my most hated tasks... binding. I cut the strips from the same purpleheart board as the fingerboard bindings and the first bridge plate. Then used an x-acto knife to slice some purfling strips from my favorite curly maple veneer.

Glue the side purflings to the bindings using hide glue. This is like traditional hammer veneering, except I use my fingers instead of a veneer hammer. Apply glue to a few inches of it, and rub the strip down repeatedly for a while, apply glue to the next few inches, and so on. No clamps necessary, and holds up great when bending, even with water.

Then cut the channel using a gramil and chisel, followed by needle file and sandpaper to clean up. I'm finally getting half way decently fast at this (a freshly sharpened chisel helps a lot).

Then bend the strips, carefully fitting to the channel. This is usully the worst part. Purpleheart is very stiff, so it needs to be bent very accurately, but fortunately it's pretty cooperative. Only the bass side waist gave me some trouble.

Here's the channel and bent strips. When using a single veneer for the soundboard purfling, I make it full height so I don't have to cut a separate ledge for it.

Trim to length, get the glue warmed up, and a bunch of tape ready to go. The soundboard purfling is one long strip all the way to the cutaway tip. Not very accurately bent, but it's flexible.

Warm the guitar as well, and glue one strip. I go about 6 inches at a time. Drown it in glue, squeeze it out with a paper towel, then tape it down. As soon as the strip is done, reheat it over the kitchen stove to reactivate the glue, and pull the tape down tighter to get a little more squeeze-out.

Repeat for the next strip, and then for the short cutaway piece. I kept having trouble getting its purfling to stay in the right spot, so I gave it a spot of glue right at the end and let that dry first.

Then add more glue along the rest of the strip, and for the binding strip, and leave it alone for a couple hours.

Remove tape, and admire the mess. I managed to get glue absolutely everywhere, including all over the bridge

Good thing it's all shellacked and thus waterproof. Several rounds of water and gentle scraping with fingernails, and I finally got it all cleaned up. Still easier than dealing with dried Titebond.

Then chisel it close to level with the soundboard and sides, and scrape the last bit. Chisel to round it over some, and file to round further and more smoothly. Sand out the file marks with 80 grit, followed by 120 and 220. Lightly scrape to remove the last traces of sanding marks, and shellac it all up.

I'm pretty satisfied with it. There are a few minor flaws. A small gap between the purfling and soundboard in the shoulder area. The cutaway miter came out good from the front, but there's a small gap when viewed from the side. The tail seam is perfect thanks to a strip of tape that I used to pull it tight together, but the runout changes and highlights it anyway And lastly, the bass side waist is still a little dark from scorching during bending. Though honestly I think it looks pretty cool, like a subtle burst shading effect.

So that's that. I think I'll French polish the soundboard next, then glue the fingerboard and do the inlays and frets, and finally close the box and string it up. If necessary, I could reopen it at that point and add more soundboard braces. Otherwise, I'll trim the back overhang, polish the back/sides, and call it done.

So, I saw in your Robin's Nest thread for the challenge that this beauty is done. Do you have any photos to update this story with? I'm looking forward to seeing how it came out.

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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

Wow, what a stellar color combination with the sinker, purple heart and a single curly maple line. Bravo!! ......Hmmm....... (rubs fingers together)....when shall I try the same thing?.....hmmm.....

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Pat

You did that on purpose, didn't you?

And you should totally copy the color combo... it is most excellent, and I'd love to see more guitars with it

Getting back to the build, I did polish the soundboard before closing the box, but ended up having to redo it. I warmed it over a fire after I got all the spool clamps on, to make sure the glue was full strength, and the clamps left impressions in the shellac. I use Old Brown Glue for box closing (hide glue with urea to make it stay liquid at room temperature), so theoretically it should be ok without reheating, but it still makes me feel better. So I'll probably have to do things in a more traditional order next time I want to do a glossy soundboard.

Anyway, after the first soundboard polishing, glue the fingerboard on:

Then sand the fingerboard radius, make any final refinements to the neck profile, and get the planet inlays all prepped up:

Saturn is the only tricky one, due to the overlapping parts. To ensure that the circle remained circular, I inlaid it whole, and then routed through it for the ring. It's a pretty soft sedimentary rock soaked in thin CA glue, so no trouble for the router.

Leveling the planets was done using my trusty XXC dia-sharp stone, followed by wet-dry sandpaper to smooth out the scratches (180 to 1500 grit), and micromesh to really polish it up.

Next come the frets. Same process I've been using for the past few instruments, where I trim them to width and shape the ends before hammering them in, so I can leave a tiny bit of space between the fret end and the edge of the board. Nice feel, and no snagging on fingernails when plucking over the board, especially in dry weather.

Installation sequence: squeeze hide glue into the slot, and poke it down with a knife to make sure the slot is completely filled. Slop water on it (pictured below) and wipe with paper towel to clear the excess glue off. Then hammer the fret in, and repeat the water/wipe to get the squeeze-out.

Then level and re-crown the frets. They never come out quite perfect after hammering, despite the board being perfect underneath.

Then do lots of tap testing with spool clamps while final-carving the braces, and close it up:

The closing process is also where I set the neck angle, although it needs to be pretty close already at this point. After applying glue, I get most of the spool clamps on, but not the ones around the upper bout. Then cam clamp that cork padded wood block on while I pull the neck forward or back. Set the guitar upright and check with a straightedge and ruler to see how high the fret plane projection is just in front of the bridge. If not right, unclamp the block and try again. When I've got it where I want it, the rest of the spool clamps go on, and then I re-check just to be sure it didn't move. I set the projection to 2-2.5mm below where I want the final string height to be. Theoretically that would make the action height 1-1.25mm, but neck relief and soundboard pull-up under string tension make it higher.

Since this one isn't going to have back binding, the last bit of woodworking is to chisel the overhang flush and round over the edge using rasp/file/sandpaper. Then on to filling the pores.

I start with 320 grit wet/dry sandpaper and alcohol to grind up plenty of wood dust slurry and partially fill the pores with it, and then switch to pumice and alcohol on a pad (cheesecloth with muslin cover) to really pack it into the pores, and to polish out the sanding scratches. Unfortunately I still got some white pores from uncolored pumice. I'd hoped making pumice-free slurry with sandpaper would prevent that, but apparently not. Hopefully this is one of those problems that magically goes away with experience, because I can't think of any other tricks to try.

Here's what the surface texture is like after filling:

Note the few patches of dry slurry still on the surface. I ended up having to scrape those off, because they still showed through as slightly darker spots after giving it a coat of shellac. Scraping pumice slurry is a tedious process, because it dulls the blade quickly. But at least it leaves a smooth enough surface in one pass, so it's still faster than sanding.

I failed miserably at French polishing, so I just went with wipe-on shellac, followed by the first 3 micromesh grits (rust, green, black), and another wipe-on coat. Slightly streaky, but good enough.


And that's pretty much it for the building, aside from the nut/saddle/etc. But not quite the end of the story, so I'll write more tomorrow, and post pictures and a sound clip.

For now, here's a closeup of the Jupiter rock that started it all

After closing the box, but before trimming the back overhang, I played it for a few months to see if I should open it back up and add more braces. It was good, but I kept feeling like it could be even better. So I did frequency plots and measured the bridge rotation under string tension (about 1.5 degrees or a bit less), and came to the conclusion that not only does it not need any braces added, it's a fair bit too stiff! So I started hacking away at the X with a chisel and finger plane through the soundhole.

I left the intersection alone (it's 3/8" tall, excluding the cap), removed a bit from the upper legs, and removed a lot from the lower legs. They curve down from the intersection height to maybe 1/4" in front of the bridge, and then gently taper to 3/16" around an inch before the perimeter, and then down to 0. I had to remove a fair amount of material from the back braces as well to get them back within 4 semitones of the top.

The bridge rotation is now right at 2 degrees, and main 3 frequencies (measured with strings on) are 98Hz, 175Hz, and 223Hz... which is unfortunate because all 3 of them just happen to be right on scale tones for A440 tuning. But it doesn't actually seem to be causing any problems as far as I can hear. I could add some mass to the soundboard in the form of a bone saddle and pins to lower its pitch, and carve on the back braces some more to lower it, which would probably drop the air frequency as well. But it sounds so good already, I don't really want to.

So two of my theories have been confirmed on this build:
1. Soundboard stiffness can be had from either the plate or the bracing, and on small guitars, you can get almost all of it from the plate because the mass will be plenty low anyway (total soundboard mass on this one is about 235g, including bridge/saddle/pins).
2. It's not a bad idea to use 3/8" string-height-at-bridge on small guitars to reduce bridge torque and allow lower soundboard stiffness. I need to build another the same size with 1/2" string height and see whether it's better or worse, but I can say for certain that 3/8" works just fine.

Without further ado, here are the photos and a sound clip

https://soundcloud.com/user-587599889/improv-on-the-galaxy-guitar

And a closeup of Saturn because it's awesome and none of the other pictures showed it clearly enough:

Dennis, that came out great!!

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Steve Smith
"Music is what feelings sound like"

Dennis

Everything about it is remarkable. The colors, the body shape, the inlays (sound ain't bad neither). Your choice of colors and textures for the planets is right on, and Saturn is very cool. Why did you put Pluto on there?

Ed

The better question is... why shouldn't I include it? The only reason is because its classification got changed. But it's still out there, and the solar system feels incomplete without it. Plus this guitar was started a few months before New Horizons sent back the first pictures of it, so it also serves as a commemoration of that event.

But if/when the mysterious planet nine is discovered, this guitar will become outdated Or perhaps the last dot could be reinterpreted, depending on what color the planet is.

Thanks for finishing out this thread. That is a very cool guitar and it sounds and looks great too. You managed to incorporate your theme into it in so many ways. The crescent moon heel is still one of my favorite features on it.

The sound gives me encouragement for the two sinker redwood sets I have that have a less than amazing tap tone.

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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