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

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

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 (5098 downloads ) and 3D design files for the turn around here.

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Building a Travel Ukulele: Sanding, sanding, and finishing

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

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

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 weeksWeeks.  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

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 []

Building a Travel Ukulele: Preparation, Marking and Cutting Frets

The last week has been more planning and preparing than actual progress.  However, this wasn’t so bad.  Cutting off chunks of wood, filing gouges into a plank, sanding areas smooth all feel like progress, but all the little steps along the way are important too.

Here’s what I worked on over the work-week:

  1. Ordered Oil and Wax.  I ordered the BIrchwood Casey “Tru-Oil gun stock finish” and “Gun stock wax,” using the last little bit of my Instructables contest winnings.
  2. Raising the Grain / Sanding.  My buddy Andrew suggested lightly wetting the wood, letting the grain swell slightly, and then sanding it back down.  I watched a short video and read an article on the topic and gave it a shot.  What do I have to lose besides $20 in wood and weeks of work?
    1. I used a lightly damp paper towel and moistened the surface of the wood.   After a few minutes, the water had visibly soaked in and the surface had become very rough again.  I used the 400 and 1500 grit sandpaper that evening and then again the following day.  Some parts are still a little rough and will probably need to be lightly sanded just a little.
    2. I sanded the fretboard area so that it was mostly smooth, but not down to 1500 grit.  I still wanted to leave some surface for the superglue to adhere the cotter pin / frets to.
  3. Cut the Cotter Pins.  This is a perfect thing to do during hot weather.
  4. Reprinting the Template.  This was another easy thing to knock out while staying inside.
  5. Planned the Bridge Bracket.  I came up with several designs.  Some are basically standard bracket sketches (the far left one looks similar to the hardware store 3/16″ ground wire straps Daniel used in his basic hand tool ukulele) and others are more novel.  I have a few designs still knocking around upstairs, so I don’t know which I’ll go with yet.  As far as I can tell, the bracket doesn’t really have to support any weight or meaningful force, it’s really just there to keep the bridge positioned correctly while the force of the strings on the turn around should keep it down and in place.
Sketches for bridge holder

Sketches for bridge holder

I also made some actual progress this weekend. Some explanations and photos:

  1. 1. Printing the Template

    1. Since I don’t want anything out of scale or misaligned, I double and triple checked my printed pattern / template against a ruler.  I’m happy to share the template, but please keep in mind at the time I’m writing this and sharing the document, I’ve never made a working ukulele.  If you’re fine with that, here’s the template.
    2. As you’ll recall, the template features a ruler on each side of the pattern, as well as a gray box 100mm long on either half.
    3. When printing, be sure it is printing at 100% unless you discover your pattern is over/under sized, in which case, you can measure against the 100mm box to easily arrive at the percentage for scaling.
    4. I also made sure to overlap the two sheets as much as the print dialog would allow, which was 2 inches.  I figured this would give me more spots to orient and align the sheets of paper as well as more surface area for gluing.
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  2. 2. Aligning and Gluing the Template

    1. I removed excess paper from the sides of the two sheets of paper.  Nothing fancy here, I just created a hard crease and tore the paper.
    2. One of the two sheets needed to be trimmed slightly, so the sheets could be overlapped without any gaps.  Once this was done, I also used a pencil to lightly draw on the top sheet approximately where the two sheets overlapped – so that I would know where to best punch holes.
    3. Modern “shrinky dinks” come with these super handy small hole punchers.  Since we did several of these projects with the kids, we’ve got a bunch of them left over.  I keep one with my craft supplies and another with my office supplies.  There were plenty of times when I’d be at a remote meeting (pre-pandemic) and want to add a sheet of paper to file or binder and these saved me from having to use the folder prongs or binder rings to puncture-rip the paper. 1
    4. To create more “registration” holes towards the middle of the design, I folded the pattern, then punched again.
    5. I wanted to glue the pattern together, but the print is on the front.  To keep the sheets from shifting, I cut up the sticky part of a post-it note, and used these to lightly affix the sheets together.  Once aligned and lightly stuck, I flipped the paper over, used a gluestick, and pressed it flat.
    6. I then used a very small (and handy!) cutting mat and my trusty exacto knife to cut out marks for the fret markers.
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  3. 3. Aligning template to the board

    1. The problem with using paper is that it’s not translucent, so you can’t really tell whether you’re aligning things properly.  To get around this problem, I used a toothpick to punch holes where the strings go into the neck past the zero fret, using some closed cell foam underneath.
    2. Using some needle nose pliers, I cut and bent two small “L” shaped pieces of a small paperclip that could be dropped through the holes in the paper into the string holes in the plank.
    3. I trimmed some of the paper and used some blue masking tape to hold the pattern steady.  I didn’t want those little paperclips having to be responsible for the entire sheet of paper not shifting.
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  4. 4. Marking locations for zero fret, frets, fret markers, and bridge

    1.  There were several steps along the way I slightly dreaded.  The first time drilling into the plank of wood, the first time I took the coping saw to the plank, cutting the round rod to size, reprinting the pattern and getting it right again, and possibly above all else putting down the lines for the fret markers.  Two people who followed Daniel’s designs reported their ukuleles didn’t sound quite right and attributed this to the fret placement.  It would be a real shame to put this amount of time into a project only to have it sound terrible.  I’ve made every effort I can to get these fret lines as precise as I can.
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  5. 5. Cutting and labeling zero fret, frets

    1. The first cotter pin I clipped ended up with both pieces flying around the room.  In an effort not to repeat the same mistake, I cut the rest of the cotter pins inside a fleece cap.  Although both pieces continued to be ejected from either side of the wirecutter jaws, they didn’t go anywhere and did no damage to the cap.
    2. The frets get progressively wider as they travel down the neck to the bridge.  With some really hot weather and less-than-ideal air quality due fires, I was pretty sure I wouldn’t be filing down the cotter pins today, so I wanted to make sure to label them as I went.  A quick fine tip sharpie mark to the topside of the cotter pin let me know where to clip it and some Roman numerals to the underside to keep them straight made sure I could easily pick up where I left off later.  As the picture captions below suggest, I used Roman rather than Arabic numerals because it’s a lot easier to write little lines and crosses on a small bit of metal than it is to write a 3 or 8.
    3. With the cotter pins clipped, I 3d printed a 15mm diameter 45mm tall screw top container to hold them.  It took $0.14 of plastic and 30 minutes to print.  Yes, it is ridiculously custom and niche, but once this project is done I will undoubtedly reuse it for some other purpose.
    4. I suspect some of the cotter pins might have gotten slightly bent in the cutting process, so I’ll need to remember to bend them flat before I glue them down.
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What’s left?

  1. Using a metal file and then sandpaper to round, taper, shape, and soften the sharp edges on the cotter pins.
  2. Making sure the cotter pins have not been bent out of shape – and bending them back as necessary.
  3. Gluing down the cotter pins.
  4. Sanding the fretboard smooth.
  5. Wood finish and wet sand, dry, wood finish again.
  6. Wax.
  7. Design / print / install bracket holding bridge in place.
  8. Install tuners (possibly with some 3D printed washers).
  9. Sand, possibly paint, and install the turn around.
  10. Add strings…
  11. Play?!!?!?
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  1. I suppose the same effect could be achieved with a non-shrinky-dink hole punch, scissors, or knife, but, I mean… why? []

Building a Travel Ukulele: Test Fitting

This barely qualifies as an update.  Or even any kind of a meaningful incremental improvement to include for this blog / project notebook.  However, I’m so pleased with the look and feel of the progress, I couldn’t help take a few pictures.

Test fit tuners and turn around

Test fit tuners and turn around

From the underside, with several prior iterations.  The very first design / print of of the turn around didn’t have large enough holes for the hex nuts.  The second version would still work, but it was about 5mm shorter than the final version and not as cosmetically pleasing.  The third version was just barely too wide.  I suppose I could have filed or sanded it to fit… but why?  I have a 3D printer and it would only take 30 minutes for another version and a perfect fit.

A 3D printed model involves very light layer ridges.  I am a little concerned these ridges could, over time, abrade the ukulele strings.  Before test fitting them, I used a very thin fine file to smooth out the grooves in the turn around.

The underside, showing two prior (shorter) iterations, bridge uninstalled

The underside, showing two prior (shorter) iterations, bridge uninstalled

In the photo you can’t really see the gap between the tuners and the wood, but you can see the tuner pegs are very slightly angled.  This is because the holes I drilled were, unintentionally, very slightly angled.  While this isn’t likely to adversely affect the tuners, string tension, or operation of the ukulele, the tuning pegs won’t sit flush against the ukulele body.  My options are either to put the drill to it again (for the third time), live with the cosmetic look, or add a washer of some kind.  I think the best option is to design a thin, lopsided washer, that I could tighten the tuning pegs against.

I am very happy with the way it’s shaping up!  It’s starting to actually look like a ukulele.

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Building a Travel Ukulele: Sanding.

There wasn’t a lot of magic to today’s work.  My time was probably 29% filing, 70% sanding with successively finer sandpaper, and 1% brushing dust.

A few notes:

  • Filing.  I bought a set of files years ago at Ace Hardware.  They had a bargain bin and a set of files – with one missing.  I asked for a discount, got it, and these have served me well ever since.  I found it helped to brush these off as I worked.
  • Sanding.  I’ve had a modest selection of sandpaper ever since I started work on my first 3D printer kit back in 2009.  On this project I used 100, 120, 150, 400, and 1500 grit sandpaper.  I believe the last two are “wet” sanding paper, but I kept the process dry – occasionally hitting the board and the paper with my brush.
  • Gouges.  I really went after these and was able to file them out for the most part.  However, there are a few spots left.  The gouge marks are small and I really felt like I hit diminishing returns on my effort.
  • Fretboard.  After a little agonizing, I decided to sand the fretboard lightly.  Now it’s smoother, but all the pencil lines are completely gone.  Since yesterday I’ve come up with some ideas on how to put these back on.1

The result is a very smooth vaguely ukulele neck shaped piece of wood.  It is very nice to hold.

I found that no matter how finely I sanded the piece, once I rubbed it with a piece of cloth2 I could feel the smallest little burs afterwards.  I think some of this may just need wait until after the first layer of finish.

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I believe most of the “outside work” is done now.  I need to:

  • Cut the cotter pins into frets.  Sand the ends down so they’re not sharp.
  • Measure and redraw zero fret, frets, and bridge lines.
  • Glue down the zero fret, frets, and bridge lines.  I would estimate roughly 99% of the chords I play are A, F, C, G, D, Dm, E7, Em, and a few similar such chords.  Really, nothing past the first fret marker.  I’ll probably do this in the evening when the weather is slightly cooler, so I can have better ventilation.
  • Once the frets are glued in place, I would probably sand between them again.  I didn’t want to make the fretboard too smooth, otherwise I might have removed some of the texture needed to form a good bond between the metal and the wood.
  • Measure, adjust design, re-print, and install the turn around.
  • I haven’t given any thought to fret markers or side fret markers.  I should probably do so now.
  • Once I’ve decided about the fret markers, I would then move on to the finish.  From viewing Daniel’s videos and other woodworking videos recently, I would wear some gloves, brush and dust the wood, apply the finish with a cloth, and then sand while it was still wet – so the sawdust could go into any open pores.  I’d probably sand again with the 1500 grit sandpaper, finish / sand again, and then move on to the wax.
  • I have some ideas to prevent the string ends from being too pokey.  Perhaps 3D printed string beads or perhaps tying the string around a 3D printed item and fed back into the holes for the strings.
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  1. Basically re-printing my design, putting hole punches in, putting the paper down, and marking the lines again []
  2. My shirt []

Building a Travel Ukulele: Filing, sanding, filing, sanding, filing…

I pretty much only make progress on my ukulele on the weekends – and even then only for a short period in morning since it gets so hot so quickly.1 Unfortunately, last Sunday I didn’t get to it – and as a result spent the workweek daydreaming about what I’d do on Saturday morning.

Here’s what I planned to do:

  • Filing and sanding.  Of course.
  • Increase the diameters for the holes for the tuners.  After a few test fittings, I found the holes for the tuners were pretty snug.  I wanted to widen these just a little to make them easier to insert, hoping they would end up flush against the ukulele body.
  • Counter sink the string holes as Daniel did on his Deluxe Travel Ukulele.
  • Cut the 3″ off the zinc plated round-rod.

I’m pleased with my progress so far – it’s not onerous, but it is slow.  As with so many things, it’s the journey, not the destination.

  • Cutting the round rod with the hacksaw went reasonably smoothly.  Rather than going for a particular length, I aimed for a length that would go from either side of the body, with about a quarter inch to spare.  I marked the spot with a sharpie, cut until I got mostly through, and bent the soft metal until it popped off.  I used my full hacksaw instead of my smaller hacksaw and it went quickly.  Then I filed down both ends so it wouldn’t be sharp.  I don’t like any of the hardware store options and will be designing a 3D printed piece to hold it in place.
  • Counter sinking the string holes and widening the tuner holes went easy enough.  I really should have done these at the beginning, but it’s all a learning experience.  I suppose I could have drilled out the turn around hole some, but the machines screws went in and came out fine already.
  • The filing and sanding isn’t difficult, it’s just slow.
    • In the photos below you’ll notice I used a soft pencil to draw in and around some of the saw and file gouge marks.  I used my medium and fine files, then started with 100 grit, then 120 grit.  I still some light gouge marks on the outside to remove, some unevenness to the neck to straighten out, and much of the interior of the body to file, shape and sand.  I also made sure to follow Adam Savage’s advice and regularly swap out the sandpaper.  There’s no point in rubbing this thing with sandless paper.2
    • The interior really jumps out as the least attractive part right now.
    • I gave the outside of the entire board a good sanding to smooth it out – except for the fretboard area.  I’m loathe to sand this part and remove the markings for the frets.  The fret and bridge positions are critical to getting the sound right and I don’t want to screw this up.
    • I took turns filing and sanding to get the shape I wanted – then started using the pencil to highlight the areas needing attention, sanding, and then an old toothbrush to remove dust.  I have a small supply of the kid’s old toothbrushes for these kinds of tasks.  After they’re done with them, I’ll wash them and use my heavy duty clippers to cut them off about 1-2 inches below the bristles.  I keep one with my drill bit set, so I can remove dust and debris from the bits before they go back in.
    • Anyhow, by the time I was done with the neck, I was genuinely surprised how nice it felt to hold.  It kinda feels like a ukulele.

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What’s next?  I’m glad you asked!

  • Still more filing, pencil marks, sanding, brushing.
    • Using my small thin round files on the string holes so they’re not so sharp.
    • With particular attention paid to the inside of the body (where it’s pretty rough) and the head (which needs a lot of shaping).
    • I’m genuinely undecided about the bottom of the ukulele – whether I want to keep it flat or round it off.  It’s a lot of wood to remove by file, so I’d probably need to cut into it again if I decided I didn’t like it.
  • Gluing the zero fret and frets.
  • Measuring and printing a new turn around.  I filed away enough of the interior that although the original turn around would work, it would look a lot better with a new one.
  • Ordering the finish and wax.  I’ll probably go with Daniel’s suggestion for Birchwood Casey gun stock finish and gun stock wax.  They’re inexpensive, come in small bottles, and are easy to order off Amazon.  I suspect a single bottle of each would be good enough for many more ukuleles than I’m likely to build.
  • I like the idea of black hardware.  I might still pick up some black oxide finish machine screws.  Or, I might just await until I finish this ukulele and see how it sounds.
  • Once the finish and wax come, it’s back to more sanding, finish, sand, finish, then wax.  :)

Things I would do differently the next time around:

  • I would definitely NOT use my awl to put such large holes into the wood.  I would have not filed or sanded off as much in many areas if I hadn’t put some of the pock marks into the wood.  I don’t know a great way to transfer the design to the wood – but I’m certain this is a problem that’s been solved in the last several thousand years by better minds.
  • Throughout this entire process I keep thinking “Dang, this would be a lot easier / faster / better looking with a bench vise.”  It would have been very helpful to have it for holding the plank while I cut with the coping saw, allowing me to keep the blade perpendicular to the wood, rather than at an angle as I held the plank with one hand and the saw pivoted slightly.  It would have been helpful with the drilling, filing, cutting the round rod, and sanding.
  • If I had a workshop or garage space I would immediately put in a work bench, bench vice, a used drill press, and a nearby station for my shop vac.  I’d be tempted to add a used band saw too.  I’ll add these to the wishlist for my next home.
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  1. It’s going to be 105 degrees in Northern California today! []
  2. Also known as “paper” []