Soprano Ukulele with LED Lighting

V3 - This is a version of my recent soprano ukulele design, that includes built in LED lighting! There are both acoustic, and acoustic-electric bodies available.  The body is printed in transparent PLA for maximum effect.

Update 9/26/24 - I've got a new and improved Model 3 tuner design.  Check it out.  I've added a new headstock designed to be compatible with them.

Sound demo and build instructions available in the video below:

Click here for printed ukulele tuners I designed to go with this uke.

I've also designed a mount to hang the uke from the wall.

If you prefer more conventional tuners, the hole patterns match Grover brand ukulele tuners, model 9NB.

In addition to the printed parts, you'll need 

• Strings for a soprano ukulele.  I like D'Addario Nytech.
• 200 mm long, 5 mm diameter carbon fiber rod in the neck for strength. The rod is available from Amazon. If you don't want to use the carbon fiber rod, there is a version of the neck available without the rod hole.
• One Number 4, 1'' wood screw to screw the headstock to the neck
• Six #2 3/8'' wood screws to attach the LED block to uklulele body
• 16 #2 3/8'' screws are also needed if using my printed tuners
• 2 #2 ¼'' screws to attach the battery holder to the battery block
• Battery holder for 2 AA batteries with switch.  I use the one from Evan Designs
• Up to 24 5 mm LEDs.  I got the Bojack 5mm LED kit for a variety of colors.  Similar LEDs are available from Digikey.
• Two, AA batteries.

If you are printing the acoustic-electric version, you will also need

• Another four, #2 3/8'' to attach the jack panel to the body. 
• Musiclily Basic Transducer Under Bridge Saddle Ceramic Piezo Pickup for Ukulele, 50mm×2.2mm, available from Amazon
• 1/4" (6.35 mm) Output 2.5 mm Input Endpin Jack, Piezo Pickup Jack, also available from Amazon.

Print Settings

• Printer brand: Bambu Lab
• Printer: P1S
• Rafts: No
• Brim : To be on the safe side, I use a brim when printing the body, since it's such a large piece.
• Supports: None of the parts require supports, except for the battery block
• Resolution: 0.12 mm
• Wall loops - 5 for uke parts.  2 for LED block parts
• Infill: 50% for uke parts. 15% for LED block parts
• Filament for Body and LED block : Sunlu Transparent PLA
• Filament for other parts : Various

Filament material: I've printed primarily with PLA as silk and wood PLAs are not as strong as regular PLA.  For example, I use Bambu Lab PLA Basic. The Bambu Lab store give materials properties for different filaments and  bending strength, bending modulus, and tensile strength of PLA Basic are all considerably higher than others like silk.

Various parts were glued together. I like Gorilla brand superglue gel. See the video for pictures of the build.

If the bridge isn't glued properly, it can pull off. I found lightly sanding the bottom of the bridge really helps. I also apply pressure using clamps for 10 or 15 minutes to make sure it is strongly attached.

Most parts were printed with 0.12 mm resolution. However, the fretboard was printed with 0.08 mm resolution. For the fretboard, I paused the print at the top of the fretboard to change filament colors, so that the frets print in a different color than the fretboard.

You'll need :

• Acoustic, or Acoustic-Electric Body
• Jack panel, if printing acoustic-electric
• The neck, or (if not using carbon fiber rod) neck - no rod hole
• Headstock - for model 3 tuners
• Bridge, or (if printing acoustic-electric) bridge for piezo
• Center ring
• Fretboard
• Five fret markers
• Strap pin, if you want to use a strap.
• Saddle
• Headstock screw cover
• Battery block for uke
• battery lid
• LED block
• 2 LED block screws
• Switch holder

If using the Model 3 tuners (my most recent tuner design), use the headstock specifically for Model 3.  If you want compatibility with Grover 9NB commercial tuners, use the original model 2 headstock design, Headstock - with inlay, or Headstock - no inlay.

The saddle is a compensated saddle. When placing it in the slot in the bridge, pay attention to the orientation. The peaks in the middle part of the bridge should be further from the top of the uke, and peaks on the edges of the bridge should be nearer the top.

For the LED block

The video above provides visual instructions on building the battery block.  A small amount of soldering is required.

It's important to use LEDs that require 3V or less, since that's what 2 AA batteries supply.  

The LEDs are soldered together.  The long lead is the positive (anode). When connecting LEDs always solder the long lead of the lead to the long lead of the other LED, and likewise solder the short to short leads.  This connects the LEDs in parallel, so that the all get the same voltage.  Then when connecting the LEDs to the batteries, the red lead (positive) gets soldered to the long lead.

In the Bojack kit, the green, blue and white LEDs require 3 V, so nothing else is needed to use them other than the Evans Designs battery holder and switch.

The red and yellow LEDs require 2 to 2.2 V.  To use these LEDs an additional 50 ohm resistor needs to be added in between the batter holder lead and the LED.

In addition the green, blue, and white LEDs in the Bojack kit are the brightest.  So I tend to use those, rather than the red or yellow.

The battery block is the only part where I use supports.

The videos below give additional build instructions for the rest of the uke build as well as for the acoustic-electric build.