Tag Archives: DIY

Building a Travel Ukulele: Improvements

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Updated / upgraded DIY travel ukulele

Updated / upgraded DIY travel ukulele

I’ve been playing my DIY travel soprano scale ukulele for about a while now and it’s been really great.  If I lightly strum it, it’s quiet enough that someone a few feet away might not notice.  If I really go for it, you could hear it across the room.  If I put a board of some kind between the ukulele and myself, it sounds considerably richer and louder.1  I started compiling some additional thoughts after the first week:

  1. String Stress.
    1. The strings seemed to stretch a little as I played the ukulele over the course of the week.  I had to slightly tighten the strings each day to keep it in tune.  The first day there was a lot of variation – and by the end of the week it barely needed any adjustment at all.

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    2. That said, the string tension has caused the strings to bite into the wood above the zero nut and seem to have caused a hairline crack in the turn around.  I suspect after a week of being stretched and compressing the wood just a little, it’s not going to continue to bite away at the wood.
  2. Zero nut, string holes, string ties.
    1. As several other builders have noted, once the strings are tensioned, they start to bite into the wood.  I tried to avoid this problem by using a hardwood, but it’s clear there is still some element of this on the ukulele.  Some ideas:
      1. Placing an additional 3/32″ fret above the zero fret and a hair below the string holes would likely prevent the strings from “biting” into the wood.  Of the various ideas that occurred to me, this is probably the flat out simplest, easiest, most immediately effective solution and involve the least amount of changes to the existing build.
      2. I’d toyed with the idea of drilling the holes out a little larger and inserting a thin plastic or metal tube which would serve as a smoother path for the string while also preventing this “biting” problem.  This would be a very complicated fix for a simple problem and involve some variation of sourcing the tubes, drilling larger holes, cutting the tubes, and glue the tubes in place without obstruction.  I’m not crazy about any of these steps – and more than that, I think it would be overkill and not have the right aesthetic for this project.
      3. My off-the-shelf ukulele has a slotted bridge, where the strings are tied into a knot, slid through a small opening, over the bridge, across the frets, the nut, and then the tuners.  There’s no reason I couldn’t put a 3D printed slotted nut at the top of the ukulele.  There are several possible benefits to doing this, with little downside:
        1. It would eliminate the need for drilling four holes in the top of the ukulele for the strings.  Printing a 3D model could ensure exacting spacing for the strings.  The plastic could be affixed with screws, bolts, or even fit over the end of the ukulele.
        2. Once the requirement for drilling small holes for the strings is removed, other interesting possibilities arise.  When I installed the Graph Tech tuners, I found they were very slightly smaller than the holes I had drilled and reamed out for the chrome tuners I already had on hand.  There’s no special need for the screws in the turn around to be #10-24’s.  Perhaps they could be screws that match the same holes drilled for the tuners?  If so, I would only need a single drill bit for the tuner and turn around holes.  (Though, it would be hard to find sweet sweet black oxide hardware to match this diameter.
  3. Turn Around.
    1. The slight crack in the turn around appears to be at just one end with the 1st / A string.  This might be the paint cracking – or the plastic itself.

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      I can’t really tell unless I loosen the strings and then pull the turn around out. (Something I don’t want to do).  I bet if I redesigned the part so the nut was placed a little farther in the model (so there was more plastic at the end of the turn around), printed with a higher infill, added more captive nuts, and/or increased the diameter of the bolts, this problem might be mitigated.  That said, it’s a very small crack, likely only superficially cosmetic, and unlikely to cause the plastic to actually fracture.

Having very nearly reached the “end” of this project… I can’t help but turn my mind to how it could be improved.  If I succeeded in building a better model, I’d have two sweet ukuleles.  If it was a horrible failure, I’d have gotten some fresh air, a little exercise, and still have one sweet ukulele.

  1. Potential Improvements / Process Changes In a New Version
    1. Saws.
      1. Japanese Pull Saw.  Upon seeing my project, two friends recommended a Japanese pull saw.  I think it would be an amazing tool – except that the way I have the “head” of the ukulele wider at the top, I don’t think it would work very well.  I sketched out a design for a different kind of ukulele template that would be amenable to a several straight cuts.  A saw like this might cost $20-40 and would save a considerable amount of time clearing the wood away from the fretboard.  This would still leave a fair bit of work on the interior of the body.  Chances are this saw would instantly justify it’s expense in the time savings on the fretboard alone.
      2. Scroll Saw.  A cheap scroll saw can be picked up new for $100-$150.  Without a big workbench, having the integrated table to go with the scroll saw would be a huge help.  I’ve ballparked my time investment into this ukulele at around 100 hours. 2  A scroll saw could be used around the entirety of the ukulele, from along either side of the fretboard, chopping the top off the head, to cutting out the interior cleanly.  I plan to do an in-depth post-mortem at some point detailing the time I spent on each aspect of the build, but I know I spent hours over weekends cutting the ukulele.  I suspect even going very slowly with a scroll saw, I could cut the entire ukulele out in a single morning with much cleaner cuts than what I could accomplish.
      3. Jig saw.  While I own a jigsaw, I didn’t use it in this project.  I wanted to use as many handtools as possible and keep the entire process about my struggle in turning this plank of wood into an instrument.
    2. Drills.
      1. Drilling.  Andrew suggested clamping a piece of sacrificial wood on the top and bottom of the board.
      2. Power Drill.  Obviously, using a power drill makes drilling the holes for the tuners, turn around, and strings much easier.  It was difficult to drill perfectly perpendicular.  However, I have some ideas…
      3. Drill Press.  A drill press would be fantastic, but too expensive for this project, too big to move or keep around.  Maybe I know someone local who has one I could use?  (The Sacramento lending library doesn’t loan drill presses)
      4. Drill Guide.  Looking through Rockler’s website I found several drill guides that allow you to drill perfectly perpendicular to the surface.  Now, this gave me an idea…  for designing a 3D printed jig / drill guide to drill through a piece of the sacrificial wood on top of the side of the wood.  I’ll come up with a sketch.
      5. Hand Drill.  Annnnnd, if I’m already creating a 3D printed jig / drill guide, why not build it with an integrated hand drill?  The drill I created is good enough in a pinch, but while researching 3D printed drills, I found this amazing pump drill which rotates in the same direction whether it is pumped up or down.  What I like about these ideas is that it is entirely possible to cut, drill, and carve the ukulele using all hand tools.  Admittedly, some tools I 3D printed, but hand tools nonetheless.  I kinda like the idea of a specialized tool for drilling holes into a plank of wood for creating travel ukuleles.
    3. Zero Nut
      1. Reinforced Zero Nut.  Just adding another 3/32″ cotter pin above the zero nut should be enough to keep the strings from biting into the wood.  This is likely the easiest solution – and easiest one to retrofit into the ukulele I’ve built.
      2. “Slotted Nut.”  I tied a knot in the strings before putting them through the string holes in the head and all but one of the string knots were pulled up into the wood.  I expect this will be a real problem when I need to change out the strings.  I think I could create a 3D printed piece which would act like a slotted bridge, but screwed or bolted into the wood above the zero nut.  It would need to keep the string lower than the zero nut, but this seems like a solvable design issue.
      3. About a month after I started writing this
    4. Bridge.  I’m happy with the bridge.  However, I noticed in Daniel’s latest video he used a metal rod with two brackets on either end to place the bridge a precise distance from the nut.  While I have no intention of making a pile of ukuleles, it would be nice to precisely place the bridge.
    5. Frets.  Some of the frets were glued in at a slight angle which will have an impact on chords, but perhaps so much I could detect.  If nothing else, some of the frets look very very slightly off.
    6. Turn Around.
      1. The turn around installed in my ukulele right now looks good – but has one minor flaw.  Since it is plastic (sanded smooth) and painted, it is a fair bit “grippier” than a piece of anodized aluminum like the tattoo grips Daniel uses.  Adjusting the tuners still affects the tension of the string – between the tuner and the turn around, but the string tends to bind over the turn around, meaning any tightening or loosening of the tuners doesn’t have an immediate change to the sound until the ukulele has been played a bit.  This makes tuning take a bit longer.
      2. I’ve come up with a design I’ll get to in a little bit, below.
    7. Wood.  I bought two pieces of wood when I started this project.  One piece of mahogany and another piece of scrap hardwood.  I thought I might start on the scrap hardwood, then progress to the inexpensive (~$10) mahogany.  I just went ahead with the mahogany first at my wife’ suggestion.  There are several other dark hardwoods I think would look really nice – and provide a stark contrast to the cotter pin frets.  If I started again, I would get a piece of wenge, zebrawood, ironwood, or walnut – just based upon the look alone.
    8. Tuners.  The Graph Tech Ratio tuners are low profile, inline, lightweight, and the most expensive single part of the ukulele at about $30 for a set.  They’re also totally worth it.  If I make another ukulele, I’ll buy these right at the start.
    9. Sound Board.  When a thin rigid box or a large piece of honeycomb corrugated cardboard is placed between my chest and the ukulele, it sounds a lot louder and richer.  However, it’s not easy to hold the ukulele properly as I do so.  I have a few ideas about creating a ukulele body shaped “soundboard” the travel ukulele could be clipped / secured into.
  2. Changes Since I Started This Blog Post
    1. I started this blog post around August 28, 2022 and am coming back to it around October 10, 2022.  In that time I made a few adjustments / changes to the ukulele.  Most of these are detailed in this instagram post on September 12, 2022.
    2. Re-Designed Turn Around.  The silver and black turn arounds had been accidentally printed at 20% infill and started to show stress fractures around the captive nuts.  The captive nuts were also seated too close to the first and fourth strings, putting extra pressure where the plastic was the thinnest.  I redesigned the turn around to put the captive nuts exactly between the first two and last two strings and reprinted it at 100% infill before filing/sanding/painting.  Since the turn around is still one solid piece, there are still minor string binding issues when tuning.

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    3. Re-Re-Designed Turn Around.  I’ve now designed a new multi-part turn around which trades simplicity for several improvements.3  It is now comprised of a “core” which looks like a thinner version of the original turn around and four “rings” which slide over the turn around to allow each string to turn that one section by itself – allowing the tuning tension to be transferred immediately to the string.  The reason for the grooves in the core is the interiors of the rings have little ridges which keep each ring from being pushed out of place.  One side benefit of this system is the captive nuts are no longer visible, creating a cleaner look.  I’ve printed, but not yet sanded and painted this version, but it looks to be the best one I’ve created so far.

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    4. Larger Countersunk String Holes.  In order to put the new turn around in place, I had to remove the strings.  Pulling the strings out was a lot harder than I had anticipated.  As I tuned and played the ukulele, the strings were wedged deeper into the string holes.  I had to use thin pieces of wire and other bits of string to get them out.  Once they had been removed, I used my DIY hand drill to widen the holes on the underside and made sure to tie additional knots in the string so they couldn’t get wedged in place.
    5. Fret Markers.  And since I was removing the strings anyhow…  I might as well install my DIY fret markers.  The fret markers are small circular cut-outs of iridescent cellophane I cut out with a hole puncher.  I put a sticky-note on the cellophane and a piece of paper on the other side, then punched.  Doing so gave me perfect little circles.  (Trying to punch out circles from cellophane without the sticky notes just tore or mangled the plastic).  I sanded the fretboard between the frets until it was as smooth as I could manage.  Then I used a glue stick on the fretboard where I wanted the fret marker and pressed it in place.  Once it had dried, I then added a few coats of finishing oil to hopefully seal the fret marker in place and then wax over everything.

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    6. Reinforced Zero Nut (“Negative One Fret”?)  Before putting the strings back in and before I added the oil and wax, I also sanded the area above the zero fret and glued in an extra 3/32″ cotter pin just barely under the string holes.  The result has been great.  The strings can’t touch the wood at the edge of the string holes, so they can’t bite into the wood causing the ukulele to go out of tune over time.  (I’m sure the strings will stretch a little, but at least I can remove one source of error).

      Gluing and holding zero fret reinforcement into place

      Gluing and holding zero fret reinforcement into place

There’s not a lot I’d do to update / upgrade / change this ukulele.  I could get to finishing (sanding, painting, natch) and installing the newest turn around and strap buttons, making a strap, and possibly a carrying case.  These are all lower priorities for me as I’m pretty much just enjoying playing it right now.

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  1. See my last post for the decibel meter readings [↩]
  2. Maybe it’s more of a Fermi estimation [↩]
  3. See later posts regarding why this turns out to be a bad idea… [↩]

Building a Travel Ukulele: Bridge, Stringing It Up, and a Sound Test!

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I’ve tended to avoid referring to this project as a “ukulele” and usually refer to it as a “piece of wood” or “plank.”  Today I’m calling it a ukulele since I was able to actually string it up and play it.

  1. Bridge.
    1. I wasn’t happy with the bridge brackets.  They looked uneven and even after plenty of time to dry, they still felt… gummy?  Tacky?  Grubby??  Not great, in any event.  I sanded them last night, again this morning, 150 grit, 400 grit, and then 1500 grit, washed them with soap, washed them without soap, set them out to dry, spray painted them again, set them out again, and this time after several hours they were dry.  They went onto the bridge and then the plastic posts in the ukulele with minimal post-processing.  It fit snugly with a little bit of force and went flush against the body of the ukulele.

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  2. Strings.
    1. I’ve never added strings to a ukulele before, so this was entirely new to me.
    2. I watched this video again and then dove into putting the strings on the ukulele.  This was another of those moments which felt a little tense.  In the end, it was really just the idea of doing something new and possibly ruining a string or a set of strings.  3D printing is so forgiving.  If I screw something up in design or printing or finish… I can just make more.  Wood and strings and metal are not so easily fixed.  Anyhow, it all turned out okay.
    3. Using what I’d learned from Soph, I decided to tie a knot in the strings, leaving enough extra so they could be fed back into the string holes, preventing any sharp bits from poking me as I played.
    4. I had drilled the string holes under the ukulele with a slightly larger diameter drill bit than the one at the top, so most of the knots disappeared into the holes.  Whenever I need to replace these strings, it will probably be a pain to get them out again, but that’s a problem for future me.
    5. I play my ukulele with a “C” tuning, so these strings my wife bought me to go in my regular ukulele worked just fine.  If you’re right handed, play chords with your left hand and strum with your right hand, then when you grip the ukulele neck in your left hand, the 1st string (A) would be closest to your fingers and the 4th string (G) would be nearest your thumb.  Going from the thumb-side to the finger-side, they would be 4th / G string, 3rd / C string, 2nd / E string, and 1st / A string.  I put a sticky note on my ukulele while I added the strings, one at a time, so I wouldn’t get anything mixed up.

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    6. After I got the strings on, I wrestled with tuning the strings.  They seemed to go out of tune pretty quickly – but I suspect this is due to the strings stretching a little.
    7. I’m glad I waited to install the strings and bridge until I had the black oxide hardware.  I’m sure the chrome or stainless steel would look great, but I prefer these design elements together.
  3. Volume.
    1. It’s a quiet instrument, but actually sounded a little louder than I would have expected.  After playing the travel uke for a few minutes, I grabbed a nearby checkbook box lid and put it between the ukulele and my body, which seemed to add a bit of volume.  As you know, I have a decibel meter from my whistle experiments, so I performed a little science for you.
    2. InstrumentDecibels
      Travel Ukulele, strumming57.9
      Travel Ukulele, playing73.6
      Travel Ukulele (with box), strumming64.8
      Travel Ukulele (with box), playing75.8
      Soprano Ukulele, strumming82.7
      Soprano Ukulele, playing94.5
    3. I was pleasantly surprised the checkbook box added so much to the volume.  It was an audible difference to myself and my family.  I may try this again with a wood box, plastic box, plank of wood, and sheet of plastic.  I have to wonder if something as commonplace as a frisbee would work well.  If so… awesome.
  4. Sound.
    1. I recorded myself playing the first few bits of House of the Rising Sun first with my store-bought soprano ukulele, the travel ukulele, and then the travel ukulele with the checkbook box lid underneath it.  I start off each 45 second sound test with a single downward strum on each chord before playing the first part of the song.
    2. Here’s a single video comprised of the three clips one after another.
  5. Turn Around
    1. The stainless steel turn around I swapped out for the black oxide ones (for purely aesthetic reasons) were only 1.25″ long because that’s what Home Depot had easily available.  Since I could choose almost any length and style, the black oxide machine screws are button head, socket drive, and 1.5″ long.  Since the ukulele is exactly 3″ wide, there was a chance the screws would touch in the center preventing the turn around from being secured in place.  Adding washers preventing this from being an issue – while also looking neat.
    2. If you’re willing to use a 1″ long machine screw, there are a lot of other potential choices for materials.  You could get bronze, steel, black oxide, chrome, nylon, etc.  I can’t be absolutely certain using 1″ screws would be fine, but I’m pretty sure it would be.  The plastic is really sturdy with thick walls, beefy infill, and able to withstand a fair amount of lateral compressive force based on how I chose to orient the print.
  6. Fret Markers
    1. I suspected that just using a hole punch on the cellophane wouldn’t work well.  I tried it anyhow.  :)  All it did was deform the cellophane.  Then I tried it again after pressing the cellophane into the sticky part of a post-it note.  I then tried punching it with the hole punch upside down and right side up.  I didn’t see much of a difference either way.
    2. In a perfect world, I would not have strung up the ukulele yet, figured out the fret markers, maybe added another layer of finishing oil, waxed again, and then installed the strings.  I was impatient, so I just went for it.
    3. Before I add fret markers, I’ll want to finish a larger piece of scrap wood1 to test the optimal glue and whether different sides of the cellophane behave differently.

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Now, the ukulele is playable, but it’s not done done.  Here’s what’s next:

  1. Figuring out fret markers
  2. Sanding and painting strap buttons
  3. Making a ukulele strap from seat belt material and heavy duty rip stop nylon, possibly with a 3D printed buckle / slider
  4. Write up a post-mortem of what I learned
    1. Always print extra parts, order extra parts, cut extra pieces, and finish extra test parts
    2. Testing materials, paints, finishes, and adhesives
    3. Be bold – maybe I’ll ruin a plank of wood, a string, or two months of work.  Or maybe I’ll end up with a ukulele.
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  1. That is to say sanding, sanding, sanding, sanding, wetting, sanding, sanding sanding, sanding, finishing oil, sanding, finishing oil, sanding, finishing oil, sanding, finishing oil, sanding, waxing, waxing, and waxing [↩]

Building a Travel Ukulele: Swapping Hardware, Fret Experiments

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Before it got too hot this morning, I spent a little time experimenting with materials before taking another scary step towards finishing the travel ukulele.

  1. Bridge.
    1. Now, I could have called it a day with the bridge brackets I designed, printed, sanded, and painted.  But, it didn’t have exactly the aesthetic I wanted.  I didn’t want to see a screw on the top of the ukulele body.  I don’t know why, I don’t have a great reason for this, I just didn’t want that.  Instead, I worked on implementing the idea I had sketched out in a prior blog post.

      What's really on the back of the Declaration of Independence

      What’s really on the back of the Declaration of Independence

    2. With several interesting benefits, the major downside to this design change is … I would be taking a drill to my ukulele after I’ve “finished” sanding, oiling, and waxing it.
    3. Today I took a deep breath and went for it. I used my hacksaw to cut two small pieces of the plastic balloon rod that I’d been using to hold printed parts as I spray painted them.  I did some test drilling on scraps of wood and tested hot glue with the plastic rod.  Hot glue doesn’t stick to everything, so I wanted to run this test before I tried.  I… probably should have done this before taking a drill to the wood again.

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    4. Once I measured the two plastic posts I discovered they were very slightly misaligned.  It’s only 1-2 mm or so, but by having the brackets like this, I can just measure, design, and print a slightly longer bracket on one side.  Which is exactly what I did.  This is another defect / variation no one other than myself (or you, loyal reader) would ever notice.

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    5. There were some intermediary steps here.  I designed and printed several different iterations that didn’t work.
      1. If you need to print something that will fit a 5.0mm diameter part (such as these plastic rods sections), you can’t have a 5.0mm hole.  You need at least some clearance to be able to fit the part.  I like to use 0.35 – 0.5 mm for parts that are supposed to move against one another regularly and 0.175 – 0.2 mm for parts that are supposed to friction fit and stay together.  I completely forgot to add this variable to my first set of prints.
      2. My second set of prints didn’t work because I had left support structures enabled and there were little bits of plastic inside the holes which I could not remove.
      3. My third set printed well – but I lost one of them and had to reprint it.
    6. These two parts have now been painted black and are outside drying in the 95 degree heat.  :)
  2. Fret Markers.  I was toying with the idea of 3D printing silver PLA on diffraction grating for a sweet rainbow-y look to the fret markers.  For a variety of reasons, I won’t be doing this.  However, why not share some of my experiences? 1
    1. I have quite a lot iridescent cellophane because I want to make these papercraft LED crystals by Erin St. Blaine.  Would it be possible to 3D print directly onto cellophane?  A sample size of 1 tells me “no, this doesn’t work.”  The molten PLA only barely stuck to the cellophane and came off the surface part way through printing.  The underside of the model wasn’t even slightly shiny from being printed on a smooth surface.  It deformed the cellophane and turned into plastic spaghetti.

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    2. Now, it’s possible the coating / surface of both sides of the cellophane were not identical.  If so, perhaps I’d have better luck?  Both sides felt the same and since I didn’t mark the side I printed on in the first place, I would have to try this all over twice more just to figure out if it worked.
    3. I also considered printing on diffraction grating – or something with a similar texture.  There are several fantastic guides for this, from pouring chocolate holograms to 3D printing rainbow reflective plastic.  Both of these methods suggest dual axis diffraction grating.  With Amazon being out of the highest “lines per inch” of 13,000 or so, I looked to possibly source these sheets directly from the manufacturer’s website website.  Thanks to Caleb Kraft, I looked into specialized 3D printing bed surfaces.  It seems like these surfaces are large stickers for metal printing beds, but might even be the same or similar to craft cutter vinyl, heat transfer vinyl, or even contact paper.  Given I want to make some really small fret markers and all of these potential surfaces were either way larger or way more expensive than I was thinking, I considered some other ideas.  Several years ago I had purchased some coin cell batteries which came with “rainbow” glasses, which I knew to be made from diffraction grating.  I pulled them out of the drawer and tore them up, you know, for science.

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    4. Going through drawers finding project scraps for experiments is the kind of thing I can do indoors at night, but in the light of day I reconsidered this process.  If you’re going to try this process for yourself, keep in mind only the smooth side is “rainbow.”  I wasn’t able to immediately tear the diffraction grating out of the glasses cleanly, so I set this part until this morning.
    5. I think I would really like to try printing on diffraction grating / holographic surfaces.  I saw a post about someone who had used “cheap holographic stickers” from ebay.  I would have tried this, except I couldn’t find anything similar on eBay or Amazon.  I did find some companies selling large rolls of holographic vinyl.  I would be remiss if I didn’t mention the 4Quarters3D shop mentioned by Caleb Kraft.
    6. And, after all this research and pontificating, I’m not using any of the above ideas.  Drilling holes in the finished wood was a little nerve wracking.  The holes drilled into the body for the bridge resulted in more splintering than I wanted, despite care with drilling and taping the wood first.  The idea of drilling even more holes into the neck does not appeal to me.  Even if I were to achieve a rainbow-y 3D printed fret marker, whether by diffraction grating, special custom 3D printing surface, holographic sticker, or holographic vinyl transfer sheet, I would have to drill a hole into the neck, sand the printed fret marker, then glue it in place.  Each fret marker would represent a new chance to splinter the fretboard.
    7. Instead, I tried something else.  What about gluing a piece of the thin cellophane directly to the fretboard?  Surprisingly, the white glue didn’t work nearly as well as the glue stick.  After the white glue dried, the cellophane flaked right off leaving a shiny patch where the white glue looked smooth.

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    8. This could have been the result of placing more glue stick adhesive than white PVA glue, variations in wood finishing under the two pieces of cellophane, or perhaps the two sides of the cellophane have different properties and I accidentally flipped one of them.
    9. I really like the iridescent effect of the cellophane on the wood.  At certain angles, the cellophane appears to disappear – and at other angles looks quite prominent.
  3. Tuners.
    1. I just got the GraphTech Ratio Tuners!  They’re gorgeous, lightweight, black, anti-backlash, and… were intended to fit holes slightly smaller than the ones I’d drilled for the shiny metal tuners I had on hand.  After watching their installation videos, I inserted a thin strip of cardstock into each of the tuner holes, which shimmed the friction fit part into place.  An awl marked the spots for the screws, my thinnest drill bit wrapped in a rubber band and insert into the DIY 3D printed drill, and then secured in place with the included screws.

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  4. Hardware.
    1. The hardware from BoltDepot.com arrived today!  I had ordered both black oxide and chrome hardware.  I lost no time at all sprinting to the mailbox, pulling out the stainless steel screws / nuts, and dropping in the black oxide  coated stainless steel hardware.  Since the wood is 3″ wide and machine screws were 1.5″ wide, I also ordered black oxide coated washers which gave it just enough space so screws can fit without a problem.
    2. It’s something of an extravagance, but I also purchased a pair of chrome plated machine screws (they only came up to 1″ long), washers, and nuts.  After playing with these a little, I preferred the black oxide.
    3. If you wanted to go with black oxide hardware without having to buy any extra parts, you could get away with one 1.25″ machine screw, one 1.5″ machine screw, two nuts, and skip the washers.  These would cost you a whopping $0.66 plus shipping.  The catch here is the shipping is $4.95, so you almost might as well splurge and try a few combinations.  The screws I purchased also require an imperial hex set, so keep that in mind.  You can find these screws in black oxide with a Phillips head, but then they only go up to 1″ long.
    4. The overall cheapest route is the stainless steel hardware in a 5-pack of 1.25″ machine screws and nuts for $1.28 from Home Depot.

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  5. Tim’s Ukulele
    1. Tim had hit me up for my pattern, which I happily shared, and then shared his own variation back with me.  I had created my pattern as a 18″ or so PDF which could be printed onto multiple sheets using registration marks.  My buddy Andrew suggested using this software by WoodGears.CA and it’s use of diagonals would help.  Tim had split up the pattern I created.  Print-soprano-travel-ukulele-template1_013_overlap.pdf (6324 downloads )   If you use his, keep in mind you’ll need to double check the printed rulers against actual rulers to ensure proper sizing, since printing to the edge of the paper can sometimes interfere with that.
    2. I’m slightly jealous of Tim’s progress.  He went from “May I see your template?” to tweeting “Did you know that you can just build a musical instrument and no one can stop you?” in five days.  I’ve been working on mine for just over two months and am only now is the finish line in sight.  :)  This latest ukulele is Tim’s second attempt, with his first shared on his Instagram page.
    3. A few notes on Tim’s build:
      1. Tim posts a lot of cool stuff made from leather.  He made a neat “back plate” / soundbox for his ukulele from stiff leather to hopefully help amplify the sound.
      2. In his first build the turn around was a little wider than the wood he used, causing it to stick out and not lay flat.
      3. Like my own build, Tim cut the ukulele with a coping saw and the tuning pegs went in “wonky.”  He used a softer wood, which caused the strings to bite into the holes, which made the ukulele go out of tune.

What’s left?  Not much!!

  1. Allow the bridge brackets time to dry.
  2. Put the bridge in the brackets, brackets on the board.
  3. Add strings to it (which I’ve never done before!)
    1. This video suggests adding a little lubricant over the frets to prevent them from abrading the strings as they are tightened and paying attention to the rotation of the tuners as the strings are added.  I’ll watch the entire video again before I try.
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  1. Which is what I’m calling mistakes… [↩]

Building a Travel Ukulele: Plancratineering

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It’s a word I just made up from “planning,” “procrastinating,” and “engineering.”

I suppose it’s also a form of mid-project optimization.  As I get closer to the finish line of this project, other ways to improve or embellish pop into my mind and won’t leave me alone until I sketch, model, research, build, and/or blog them.

  • Hardware.
    • Initially I bought the cheapest hardware possible, stainless steel or zinc plated stainless steel.  However, without a big jump in price, I could “upgrade” to using black oxide coated stainless steel for a more uniform and understated look.
    • To start this project, I went with two #10-24 stainless steel machine screws and two matching nuts was only $0.52 and came with free shipping from Home Depot.1
    • “Upgrading” to black oxide screws through BoltDepot.com is more expensive, but still an inexpensive addition.  The cost of two #10-24 black oxide coated machine screws and matching nuts is $0.64.  I could even swap in chrome plated machine screws and matching nuts, for $6.68, which would look pretty cool.  Their shipping cost is basically $5 for small packages such as this.
    • I suppose if I was somehow swamped with demand for custom 3D printed turn arounds, bridge brackets, strap buttons, and hardware, I might try bulk-ordering from BoltDepot.com or McMaster-Carr for a discount and then putting together kits.  I do not anticipate this happening any time soon.  :)
  • Strap Buttons.
    • I don’t have a strap to go with my ukulele, but I’d either make or buy one if it was really working out.  Strap buttons are relatively cheap as an off-the-shelf item ranging from $5 – $15 depending on how fancy they are.  However, I’ve made an effort to keep everything as “DIY” as possible.  Once done, I think the only off-the-shelf instrument items will have been the strings and tuners.
    • All the strap buttons I’ve seen appear to be very similar.  They’re just little tapered cylinders with a hole for a screw to go into the wood.  These would be very easy to design, print, sand, and paint to look really nice.  And, best of all, there are tons of websites which show cross sections and dimensions of many different variations for these buttons.2  The only real decision, of course, is what color.  Black, nickel, or chrome seem to be my knee-jerk preferences.

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    • I looked at these various options, considered the size of my project, constraints of 3D printing design, and came up with a model that I felt would look really nice once it was sanded, sanded, sanded, sanded, sanded, and painted, sanded, and painted. 3  Each button costs about $0.03 worth of plastic to print, using about 1.1 grams of plastic.  That’s a pretty good deal if you completely discount my time.  :)  Something I did not realized until after I had waited 7 minutes for a high polygon version of this design to render was that once I printed and quadruple sanded the printed button, it wouldn’t matter how detailed the model was.  After that, I dropped the facets by a lot and had renders done in about 15 seconds.

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    • The ones I’ve printed seem to look nice.  I’ve printed 5 in all.  I figure I’ll sand4 two of them, paint them, and see how they look.  If they’re anything like the turn around, I’ll be very happy with them.  Two extras are in case I don’t like the look of the black strap buttons and want to see what it looks like with some silver spray paint.  The last one is in case I find a way to really screw up one of the others.  Worst case scenario, I give away or sell these, I suppose.
  • Strap.
    • There are a bazillion ukulele straps out there.  I just added one to my wish-list, the “Hug Strap” by Melissa Nannen for use with my regular ukulele.
    • However, for this ridiculously DIY and handcrafted project, I’d want even the strap I use with the 3D printed buttons to be a DIY item as well.  I have a sewing machine, heavy duty thread, thick nylon seatbelt material in black and dark gray, and several different thicknesses of black and gray ballistic nylon like you’d see in camping gear or a heavy duty backpack.  I’m pretty sure I could whip something up.
  • Turn Around.
    • I’ve now made several different turn arounds.  There were two or three iterations just to get the width and sizing properly calibrated.  Then I made a silver one, followed quickly by a black one.
    • Then I remembered I had thought of a few ways to make a fully round one.  The fully round one would have a slight seam that would probably disappear once it had been sanded and painted, but half of it would have to be printed with support structures, possibly making it a little rougher to begin with.  Though, there are several design tricks to minimize these issues.  It could be designed with a larger and a smaller side or perhaps with two identical halves that fit together.

      Two sketches of ideas for 3D printed two-part turn arounds

      Two sketches of ideas for 3D printed two-part turn arounds

    • Now, turn arounds with beveled edges and grooves at 45 degree angles could be printed on their ends, but these introduce several potential problems.
      1. Printing on the end makes it harder (though not impossible) to include captive nuts.  You could create slots for the nuts to be dropped into – or pause the print and drop nuts into the model as it’s being printed, permanently embedding the nuts into the model.  This could actually work really well, now that I think about it.  Of course, cleaning the threads for the nuts if they get plastic in them or other debris would be difficult, but it might be worth the one-time extra design / printing effort.
      2. Printing on the end changes the direction of the 3D printed layers.  A print tends to be slightly stronger and be less likely to “delaminate” when forces are applied along the “grain” rather than against the layers.  Simply put, over tightening a turn around that was printed “laying down” is less lightly to cause a problem than a turn around printed on one side.
    • What I like about the current turn around is (a) it’s already done and (b) I kinda like how you can just barely see the captive nuts inside.  This doesn’t actually detract from the look for me.  What I like about the idea of a “fully round” turn around is that it may look “cleaner” and more “professional.”  I realize the  ship sailed on the “professional” look the moment I took the coping saw to wood.  The two legs of the body aren’t even, the interior cutout is obviously not symmetrical.  That’s not to say it looks bad – it just looks… unique.
  • Fret Markers.  I have not given up on fret markers.  I watched an interesting video showing how someone laid out the correct spots, tested the materials, and inserted their fret markers.  I gave some thought to how I would add my own.  It occurred to me I could use 3D printed markers printed on double axis diffraction grating in a technique pioneered by David Shorey.  I think some “raw” silver PLA embedded with diffraction grating patterns would look really nice.
  • String Winder.  I printed a String Winder from Printables, but the winder was too small for the tuners on my ukulele or the ones I have test-fit into the project wood so far.  I designed a new one in OpenSCAD, printed it and put it to use.  I designed another as a “bonus” feature for my recent Instructables entry in the “Make a Tool” contest.

Lastly, as I get ready to turn in for the night, I realized I got a lot of little things on or for the ukulele done this weekend – but still haven’t finished designing my ideas for the new bridge bracket.  I don’t really mind.  I feel like I’m still making progress, still moving the project forward, albeit slowly.  Again, I’m not really in a rush here – I’m enjoying the process immensely.

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  1. Actually, the pack of 5 screws and 5 nuts was $1.28 [↩]
  2. There are lots of options on AliExpress, Amazon, and Walmart, but they don’t need the SEO juice just for me to show you a few examples [↩]
  3. Why do I keep putting my sandpaper away, knowing full damn well I’m probably going to need it again really soon? [↩]
  4. Etc [↩]

Building a Travel Ukulele: So Much Experimentation, Bridges, Printing, and Sanding

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I’ve been lightly working on the ukulele before work in the mornings over the last week and today (Saturday).  I feel like the finish line is finally in sight.  So much so that I watched a video on how to string a ukulele.  My plan is to replace the strings on my regular uke and put the old ones into this DIY travel ukulele.  I’ve never replaced these strings on my ukulele and a close inspection of the strings reveals they are visibly worn under the first four frets or so.

Anyhow, before I turn to build progress…

I'm going to have to science the shit out of this

I’m going to have to science the shit out of this

  1. Wood Finishing.
    1. I did put a fourth coat of finishing oil, sanded with 1500 grit, dried, buffed with a paper shopping bag, and added two coats of wax.  I was curious how much finishing oil and wax I used.  Since I didn’t measure the oil before I started, I’ll extrapolate from the weight of the wax.

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    2. Before using the wax, the bottle weighed 3.235 oz.  Thus, I used about 0.096 oz of wax1 and approximately 0.173 oz of oil.  This suggests a pair of these bottles should last someone for a little more than 17 similar travel ukuleles.

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  2. Paint Tests.
    1. I have been thinking about fret markers and how I want these to look.  I thought it might look nice to have them in the silver spray paint, but the wood has four coats of finishing oil and several coats of wax.
    2. Thus, I pulled out a trust pieces of scrap wood, sanded it with 120, 150, 400, and 1500 grit sandpaper, (finishing oil + 1500 grit sandpaper) x 4 times, then two coats of wax.  I did this in 95 or so degree weather, so each coat dried very fast as I rubbed / sanded each one in.  A true test would have been to let it dry for hours, but this was just to get a sense of whether it was feasible to spray paint sand finished wood.
    3. After I had “finished” this small bit of scrap wood, I sanded all those layers and hard work off of part of it.  I used a hole puncher to cut small circular holes in some blue tape, put a piece down over the finished area and another over the finished + sanded area.
    4. This was spray painted silver, dried, and the tape peeled off.  This is a very small sample and sample size, but the blue tape over the finished and unsanded area seemed to bleed into the grain while the blue tape of over the finished and sanded area didn’t bleed at all.

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  3. Bridge Bracket.
    1. I need a way to install the bridge.  Ideally, I would have a little metal bracket like Dan’s models.  Then again, I have a 3D printer, which means the solutions to all my problems can usually be solved with PLA.  I designed a very small bracket and test fit it over the steel rod.

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    2. It occurred to me that I’m not really sure what “color scheme” I want.  I have lots of colors of plastic, a few colors of spray paint, and lots of other color paints.  Time to experiment!
    3. I thought back to a quote I think about sometimes when I’m 3D printing things.  “First rule in government spending: why build one when you can have two at twice the price?”  S.R. Hadden from the movie adaptation of Carl Sagan’s Contact.  If I’m already running my 3D printer, why not print a few extras and try out all the permutations?

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    4. I generally like to measure 3D printed things in grams, since it makes it easy to convert to kilograms, and estimate the cost to produce parts.  Unfortunately, I had left the digital scale in “oz” mode.  Running the numbers, the brackets are 1.05 g per pair (about $0.03) and the turn around was 5.61 g (about $0.14).  The weight and price estimates don’t include minor support structures, the plastic skirt to prime the extrusion, electricity, or amortized cost of the robot but these probably wouldn’t add more than a penny or two to each part.
    5. I wasn’t sure whether the silver and black paints would stick well or cover up the imperfections in in the parts, so I printed four sets of the brackets.  I would sand two sets, then spray paint one of each type with silver and one of each type with black.
    6. I set out the bridge brackets on some scrap cardboard on top of looped blue tape and hit it with some spray paint.

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    7. It will surprise no one, but the sanded parts look a lot better.  Based upon the time stamps on the photographs, I would estimate it took an hour to sand the little plastic parts.  One side effect of sanding parts this small is that I frequently had to hold them in my fingers as I sanded them and my right index finger is a little bit raw.  I think if I only sanded the small parts with my finest sandpaper, this might not have happened.  By the time I was done, I was already leading towards the black hardware.
  4. Assembled.
    1. Some photographs of the final hardware options – the silver/black bridge brackets and silver/black turn arounds.

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  5. A teeny tiny issue…
    1. I designed the bridge bracket without actually having screws to go into them.  I took the measurements from the screws for the tuners.  This means I need to use one of those screws or find two more small screws of about the same size.  This is not as easy as it sounds.  Unless…
  6. Swapping Hardware / Cosmetic Issues
    1. Nuts and Bolts.  The bolts and nuts I have are fine.  Shiny inexpensive metal, they proved the concept for my turn around, but aren’t exactly what I want.  As I took the assembly photos, I couldn’t help but think back to my search for black oxide parts.  I can find some black oxide imperial hardware that is inexpensive through BoltDepot.com, but the bolts are only up to 1.0 inches instead of the 1.25 inches I’m using.  This isn’t a huge problem since the plastic turn around is almost certainly far stronger than it needs to be.  I can even get black oxide nuts to go with them.  The wood screws for holding the bridge in place is a little trickier, but they have these too.  The total price tag for several duplicates of these parts is well under $5 with another $5 for shipping.  On the other hand, I could go with McMaster-Carr and get the exact size, shape, color, and head for these parts, including the nuts, but it would cost about $30 plus an unknown shipping amount.
    2. Bridge.
      1. When steel is really heated up, it can get a bluish tint to it.  The bare metal bridge is “okay” but doesn’t wow me.  I’m tempted to play with this before I install it.  For a minute I was also tempted to get some “Super Blue” to turn the steel rod black.  :)  This is a ridiculously frivolous expense for a very slight cosmetic change.  I can’t justify a $14 expense to change the color of the metal bridge.  Chances are I could just sand and spray paint the stainless steel rod with the black spray paint for the same net effect for no additional cost.  Of course, this would also mean hacking a test piece off the nearly 33 inches of zinc plated rod I still have and then testing it with some flames and/or spray paint, but this isn’t so bad.
      2. Then again, I could also try out styrene rods (but it looks like they’re all white) or carbon fiber rods (tend to be pricy).
      3. As I’m thinking about this another design for the bridge bracket popped into my mind.  It has the bonus of not putting extra visible holes into the wood, not affixing the bridge in an obvious way into the wood, and would make it easy to swap out bridges or even bridge diameters if I felt like it later on.  The only “downside” is that it would require a larger hole drilled into the thin wood of the sides of the ukulele.  A sketch:

        What's really on the back of the Declaration of Independence

        What’s really on the back of the Declaration of Independence

      4. With this design, the strings would keep the bridge pressed down, which would keep the bridge brackets pressed down, but since they are pressed down, the brackets can’t slide off.  If I ever wanted to swap out the bridge, I would just need to loosen the strings, lift one bracket off it’s peg, and then remove and replace the bridge.  I don’t see any reason why the vertical peg I drew above couldn’t be part of the design of the bracket too.  There are a few minor problems with this plan:
        1. I would have to take my drill to the ukulele again… after I’ve spent so much time sanding, sanding, oiling, sanding, sanding, sanding, oiling, sanding, sanding, buffing, sanding, sanding, sanding, sanding, sanding, sanding, oiling, sanding, oiling, sanding, sanding, waxing, buffing, and waxing.
        2. I would have to redesign, print, sand2 , and paint the new brackets.  This doesn’t really bother me so much.
    3. Tuners.  There’s an event coming up and this time and I put new tuners on my list.  This feels wasteful to me since I have literally never used the $7 tuners I got off Amazon (you see them in every photograph of the assembled ukulele).  At ~$33 the GraphTech tuners are small, lightweight, wouldn’t protrude below the ukulele body, flat black, and even used by Daniel Hulbert himself.  This feels like a bit of a splurge – but one that’s worthwhile.  Normally I don’t want anything for my birthday except to spend time with loved ones, but this year it’s one of two things I’ve put on my list.3

Okay!  What’s up next?

  1. Redesign the bridge brackets.  Print, sand, paint.
  2. Drill holes in the wood (shudder) for the new bridge brackets.
  3. Drop in the bridge and bridge brackets.
  4. Stings
    1. Play my ukulele one last time, sore fingers permitting.
    2. Remove and replace the strings with the new ones I have ready to go.
    3. Put the old strings into my travel ukulele!

By gum, I might well have this finalized tomorrow!!!

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  1. With some of it getting on my hands, the cloth, gloves, and a drop here or there on the surrounding cardboard [↩]
  2. With, you guessed it, 120, 150, 400, and 1500 grit sandpaper [↩]
  3. Both ukulele related, haha [↩]

Building a Travel Ukulele: Finishing, sanding, painting, etc

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As I suggested yesterday, I began the rewarding process of applying finishing oil to the wood.  After the wood had been sanded several times, I applied the oil to a clean cloth, wiped it on and rubbed it in.  I then hung it inside a cardboard box outside in the warm weather for 3-4 hours, added another coat, rubbed the oil in with 1500 grit wetsanding sandpaper, let it dry, added a third coat with 1500 grit wetsanding sandpaper.

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While the coats were drying, I pulled out the 3D printed turn around which I had sanded smooth last weekend, popped it onto a plastic rod from an old balloon, and hit it with some 13 year old silver spray paint.  Here’s the collected progress photos on the turn around:

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Here’s the latest photo of everything very nearly fully assembled:

Nearly fully assembled! I just need something to hold the bridge in place, the hex nuts for the tuners, and strings

Nearly fully assembled! I just need something to hold the bridge in place, the hex nuts for the tuners, and strings

What’s next?

  1. Deciding whether I’m going to add a fourth coat of finishing oil or give it a final buff with the paper shopping bag and move on to waxing.  Setting aside the lighting differences in the above photos, I didn’t see a big difference between finishing coat 2 and 3, so coat 4 might just be diminishing returns and a way to plancrastinate finishing the project.
  2. Designing a small plastic bracket for the bridge.  Deciding whether I want to keep it raw 3D printed PLA, paint it black, or paint it silver.
  3. String it up!
    1. If all goes well, I’d definitely spring for the GraphTech tuners to give the ukulele a lower profile.
    2. If it doesn’t go well… I suppose it’s back to the drawing board…

Lastly, a shout out to my new friend Tim who messaged me about a copy of my template.  Soprano-travel-ukulele-template_013_v2.pdf (5063 downloads ) and 3D design files for the turn around here.

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Building a Travel Ukulele: Sanding, sanding, and finishing

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Normally I only work on the ukulele at night or on the weekends.  However, of all of the steps, I’ve been really looking forward to adding the wood finish, since that’s when all of the hard work will really start to become visible.  This morning I:

  1. Sanded.  Gluing the frets down went reasonably well, but about three of the frets flipped upside down into the super glue, were placed back, and had super glue gunk on the top.  I did not want that to cause unnecessary friction or abrasion on the ukulele, strings, so hit the entire ukulele with 150 grit, 400 grit, and then 1500 grit sandpaper, even over the frets, to smooth it out.  There’s a before and after picture below, all you really see is that the super glue in between the lower frets looks slightly less obvious.  I tried wet sanding with the 400 and 1500 grit sandpaper, but this sandpaper is charcoal grey and left kind of an ugly residue I had to keep wiping off with a paper towel.
  2. Buffing.  I don’t know what else to call this step, except that I’d seen a YouTube video by a woodworker who said he takes a paper shopping bag and rubs down his projects with it after sanding, since it will remove extremely fine burs from the wood.  We have a ton of paper shopping bags and I didn’t have a lot to lose by trying this.  Worst case scenario I end up with some polished paper bag scraps and best case the wood plank is very slightly smoother.

Time Spent:  Just under 2 hours.  Since I take photographs before/during/after these steps, I’ve been able to estimate the approximate time spent.

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I don’t have a lot of pictures of the next step, so you’ll just have to take my word for it.

  1. Cardboard Enclosure.  I used an old cardboard box, large corrugated cardboard scraps, and hot glue to create a rigid box with a narrow opening at the top where I could hang the ukulele by a thin plastic rod running through the tuning peg holes.  I learned this trick from watching Soph’s video.  :)
  2. Finishing.
    1. The reason I don’t have any photos of this process is I was wearing rubber gloves and using a scrap of clean laundered cloth to liberally apply the wood finish.  My fingers and the wood were tacky with the finish and I didn’t want to take off the gloves for photos.
    2. The mahogany greedily soaked up the finish quickly and I kept adding more.  This was exactly as satisfying as I had hoped it would be.  The wood finish made the lighter parts of the wood grain take on a golden shine, deepened the color of other areas, improved the look of the areas between the frets, and by the time it soaked into the wood around and under the super glue smears, those smudges were almost imperceptible.  The wood took on a rich, deep tone.
Finishing oil applied, drying

Finishing oil applied, drying

Up next

  1. While the ukulele is drying, I’ll spray paint the turn around (I’ve got silver and black paint)
  2. Sand the wood again, wipe down with a clean dry cloth, add more finish, dry again
  3. Add tuners, bridge, turn around, strings…
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Building a Travel Ukulele: No Turning Back

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Preparation can be a form of procrastination.  As long as I was planning to make a ukulele, I didn’t actually ever have to start doing it.  There were a few points along the way where I was hesitant to take the next step.  Drilling into the wood for the first time.  Trying to cut tight curves with the coping saw.  Raising the grain by wetting the entire plank and sand it back down.  The step I’ve been looking forward to the least so far is gluing down the frets.

I haven’t used super glue in a very long time.  I used it in building my MakerBot Cupcake CNC more than 12 years ago, but not since.  Once the first bit of super glue goes down, that’s it, there’s no turning back.  So, of course, I plancrastinated just a little more.

  1. In re-watching Daniel’s video for his hand tool ukulele, I saw he glued the frets down over pencil lines.  I was worried about trying to do this – concerned the pencil graphite would prevent the frets from adhering.  However, if it worked for Daniel, perhaps it would work for me too.
  2. I re-re-printed the pattern, cut out some thin slots so I could quadruple check the fret spacing.  I made pencil marks through the slots, then used a metal straight edge to draw the lines back in.  By holding the ruler at an angle, I was able to put the pencil right against the straight edge.

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  3. I ran blue tape along both sides of the neck, so that I could extend the pencil lines to ensure the frets were straight.
  4. I wanted to test how well the super glue held down the frets, whether I should sand the board a little more, and whether I should sand / shine the underside of the frets.  The answers were:  very well, no, and no.

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    1. I tested the glue and frets with some cotter pin cutoffs and scraps of wood.  I took four cotter pin pieces and sanded two so the underside was shiny.  The flat side of each cotter pin half had this gray residue underneath.  One scrap of wood was a lot rougher than the other.  I figured by mixing these variables, I could get a sense for how quickly the glue would set, whether it was better to glue to a rough or smooth surface, and whether it was better to glue to a raw cotter pin underside or one I had sanded to a shine.
    2. In order of best to worst it was:  unsanded cotter pin on rough wood, sanded cotter pin on rough wood, unsanded cotter pin on smoother wood, and last sanded cotter pin on sanded wood.  An important factor in each was to put the glued frets under pressure.
  5. I put several rubber bands around the neck, then slipped popsicle sticks underneath.  My hope is these would help hold the frets in place and keep them under pressure as the super glue dried / cured.
  6. I was finally out of runway.  I was finally at the point where I needed to put glue on the plank I’ve been working on for six weeks.
  7. I pulled out the zero fret and 15 cut, filed, rounded frets and stuck them into a piece of closed cell foam to keep them organized and easy to reach.  I put down three lines of super glue, dropped the first three frets, then held them down with the rubber band popsicle stick combo.  Then another three frets.  Held those down with popsicle sticks.  Then another 4 and the last 5.
  8. I used an extra bit of cotter pin and my pliers to nudge the frets in line.  Two frets flipped over when I tried to place them.  Explicatives were uttered.  I used the cotter pin and pliers to flip them over and nudge them into place.  However, this resulted in the super glue smearing over the wood and glue getting on the top of the fret.  The glue smear was particularly disappointing since it discolored the wood.  I’m hopeful that after I sand the frets to remove the glue gunk, smooth the spaces between frets, apply the finish and wax, the smear won’t be as noticeable.  Last of all, I glued the zero fret and used some more popsicle stick rubber band magic to hold it in place.  I think fret 15 is slightly crooked.

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  9. I propped the plank against a warm window to let it cure.

Next up:

  1. Sanding the fretboard and gummy glued frets
  2. Wood finish and wet sand, dry, wood finish again.
  3. Wax.
  4. Design / print / install bracket holding bridge in place.
  5. Install tuners (possibly with some 3D printed washers).
  6. Sand, possibly paint, and install the turn around.
  7. Add strings…
  8. Play?!!?!?
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Building a Travel Ukulele: Building a Drill

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As I suggested in a prior post I mentioned how the tuning pegs were slightly angled because the holes I drilled were, unintentionally, slightly angled, causing the the tuning pegs to not sit flush against the ukulele body.  You can see the slight angle of the tuning pegs – and the gap on one side for every tuner.

Test fit tuners and turn around

Test fit tuners and turn around

I initially felt my “best option” was to print thin lopsided washers.  This was, of course, a total garbage idea.  Ever time I did a test fitting, I knew I would hate it.  Every time I played the ukulele, it would bother me.  I would always know there was more I could have done to make it better.

This had been bothering me for weeks.  Weeks.  I just checked the photos going back to my first test fitting.  Six weeks.  I knew I wouldn’t be able to let this go.  I couldn’t live with a stupid looking gap between the tuners which would inevitably collect dust or grime.  I also didn’t want a 3D printed washer obscuring the shiny tuners.  That meant drilling the holes.  For a third time.

The first time I drilled these holes, I had propped the plank on it’s side, sandwiched it between two short boxes, and drilled downwards as straight and as perpendicular to the wood as I could.  Frankly, I did really well for some bozo with a drill, some boxes, and his kitchen floor.  These holes weren’t very far off, but still off enough to angle the tuners and create that gap.

The second time I drilled the holes, I just held the board down with one hand on some scrap wood outside and the power drill in my other hand.  It wasn’t even close to steady, but it did widen the holes a little.  I’m just glad I didn’t really screw up the wood in this half-assed process. 1  This was successful in that all the pegs fit a little better, since the holes were slightly larger, but I knew I couldn’t get the control I needed with my drill.

It was around this time I noticed the latest Instructables “Build a Tool” contest.  I’m a big fan of Instructables.  It’s a great place for people to share pretty amazing projects, tips, photos, and write ups.  I have an Instrucables t-shirt I wear proudly, a few patches, and a second place win in Origami and another in Cooking.  (In both instances, I’ve spent my Instructables winnings on this very project.)  Anyhow, seeing this contest made me think… could I create a drill?  I could really use a single hand, high precision, medium torque, low speed drill – something I could have really fine-grain control over.

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As you may have come to expect, I created several versions.  I started (as usual) with a quick sketch, then an OpenSCAD model, a test print of a thin slice to make sure the nuts would fit in the appropriate slots, printed the full model, used it, then redesigned it from scratch in TinkerCAD, printed a slice, test fit that, printed the whole thing, and then used it.  The OpenSCAD model was easier for me to design, since it’s been my program of choice for more than a decade, but the model used 50% more plastic, was rounder, yet chunkier, took longer to print, and kept loosening as I tried to drill with it.  The TinkerCAD model was harder to design (I used several design tricks that would probably justify an entire blog post unto themselves) due to my relative unfamiliarity and the lack of an intersect function, but was thinner, used a lot less plastic, printed faster, felt nicer, and worked much better.  I think printing the model with slightly undersized screw holes (by accident) really helped, since it didn’t let the machine screws slip as much.  I used my standard “coarse” functional part settings of 0.28mm layers, 3 walls, and 15% infill.

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This drill worked really really well for my purposes.  It worked so well, I’m just going to keep it in my drill bit case forever.  It may not use it often, but if I’m out of power or am building another ukulele, it could come in handy again.  If you want to get really technical, maybe I didn’t so much “drill” these holes as I used a custom drill bit holder to rotate and ream out an existing hole.  This last iteration of this drill was so solid, there’s no doubt in my mind you could use it to actually drill a hole.  It would be slow, but you could control the process, and the machine screws perform double duty as both a tightening mechanism and as handles giving you extra leverage to rotate the drill bit.

If you want the STL files, I posted them over on Printables.

What’s next in the building a travel ukulele saga?  I’m glad you asked:

  • Double checking the measurements of all fret marks on the neck
  • Apply de-stickified blue tape along the neck on both sides
  • Marking the locations of the frets on the blue tape, to either side of the frets
  • Wipe down the neck with a clean dry low-lint cloth to remove dust
  • Super gluing the frets in place
  • Sand, wipe down
  • (Finish, wet sand with finish, dry) x2
  • Wax
  • Design bridge holder, install bridge
  • Install tuners
  • Install strings

I’ve spent way way way too long overthinking and planning this project.  I do tend to sometimes kill projects through over thinking.  Then again, it’s not all bad as traits go.  Heck, it’s an advantage in my line of work.  I know now if all this thinking and planning and writing will ever result in something playable.  I hope so.  Maybe it will just be an anecdote I tell years from now about how I managed to stay sane during a global pandemic, distanced from family and friends.

It’s late and I’ve been in a pensive mood.  As I’ve been working on this project, I’ve reflected upon friends and family, near and far.  Cutting and filing and sanding are repetitive, almost meditative tasks.

  • My wife, who’s always supportive of my latest harebrained plan.  She bought me the ukulele and has suffered through countless bad notes long after the kids had run to the furthest corners of the house to hide from my playing.
  • My dad, who built amazing things through reading, research, meticulous planning, and, above all else, sheer force of will.  I would have liked to build this ukulele with him.  Maybe this version will be complete garbage and we will.  Maybe this version will be great, and we’ll build a better one together.
  • My mom, a fountain of endless curiosity and positive energy, an absolutely  unstoppable force of nature.
  • Matt Stultz, who entertained my printable ukulele questions back in 2016 and suggested the tuners I purchased, which sat in a drawer for nearly 6 years.
  • Matt Arnold, who doesn’t realize it, but gave me the push I needed in a conversation on 3/22/2022.  I was nudging him to work on his book – and he was pushing right back.  “Afterall, a ukulele won’t make itself…”
  • LawMonster13, and fellow Roger Zelazny fan, because he’ll remember a favorite quote, “Wish in one hand and do something else in the other, and squeeze them both and see which comes true.”
  • Andrew Murdoch, who is very likely my most loyal blog reader, for his woodworking and sanding suggestions.
  • Daniel Hulbert, and his incredibly detailed free DIY ukulele plans.  Though we’ve never met in person, perhaps one day we’ll get to hang out for a bit.  I’ve spent a lot of time reading and re-reading his blog posts, reviewing photographs, and watching his videos for tips and pointers.  It’s hard not to feel like you are at least a little familiar with someone after reading/watching so much.  I’m literally coming up on two years since I first found his CircuitsAndStrings website and plans. 2   Using these designs, I tried designing a 3D printable travel ukulele, but none of my printers were large enough to test any of my designs.3  It wasn’t until 3/22/2022 that I really got started on this project, coming up with some ideas and plans based upon Daniel’s designs.

This has gone one way longer than I would have expected.  Indulge my curiosity.  If you made it this far, send me an email or leave a comment.

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  1. Again, a bench vise would have been an amazing help. [↩]
  2. Based upon his designs I downloaded, I believe this was 8/17/2020 [↩]
  3. Based on my files, I worked on this from around 5/8/2021 until around 6/6/2021 [↩]

Building a Travel Ukulele: Shaping Frets, Sanding

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I’ll start with some spoiler pictures, already posted on my Instagram account:

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It was a very busy week at work, so I didn’t get a chance to work on the ukulele until this morning.  I needed to shape the ends of the frets so they won’t be sharp and pokey while I’m playing, sand the 3D printed turnaround so it won’t abrade the ukulele strings, and general sanding of the wood body.

I don’t have a lot of pictures for it, but I sanded and wet sanded the 3D printed turn around.  I used an old compostable tray left over from some prepared food.  I just needed something to hold a little bit of water while I sanded the turnaround.  There’s nothing fancy about this part.  I sanded the turn around with 120 grit to get it mostly even, 150 grit to smooth it out a bit, then 400 and 1500 grit wet sanding paper to get it nice and smooth.  I’m anxious to get this ukulele built, so I’ll probably install the turn around as-is.  If the ukulele sounds good, I’ll remove the turn around, hit it with a light coat of spray paint (black or silver), and then reinstall it.

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You’ll note the small 3D printed capped container.  It’s a 45mm long, 15mm diameter double knurled cap version of this “Customizable Container with Knurled Lid” from Thingiverse.1  I’ve been posting things to Thingiverse since 2009 which almost seems like ancient history now.  MakerBot launched the Thingiverse customizer in late 2012 or early 2013 and, unfortunately, 9 or 10 years down the road this functionality no longer works.  This handy utility allowed makers to share not only their designs, but permit people unfamiliar with 3D design or programming to obtain custom STL’s of those designs.  Although this tool no longer works, the underlying OpenSCAD code is fortunately still available.  I used the script for the CCKL to create a small, narrow screw top container that was the perfect size for holding the frets, two machine screws, and two nuts.

Having a bespoke case for parts was a game changer for the way I work on projects.  With a day job, kids, limited work space, and a longer term project, I frequently have to work on a project and then put it away for an hour or a week until I can have the time and space to come back to it.  By putting a set of small parts into a custom container (that I could conceivably label) I can keep everything organized together.

I have spoken.

I have spoken.

Filing and shaping the frets was time consuming, but not arduous.  Based on the the time stamps in the photographs, I spent a little over two hours filing and shaping the frets and sanding / wet sanding the turn around.  I first flattened or bent flat each fret, then used my finest hand file to taper the end of the frets, rounded them off, then removed burs.

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While I was at it, I sanded the ukulele body a little more with the 1500 grit sandpaper.  Taking time away from the project and then coming back allowed me the distance to find a few new slightly rough patches.  I think there’s a few more to go, but nothing that will ever really matter.

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  1. (CCKL) = Customizable Container with Knurled Lid [↩]