Baritone Triotune - Playable 3 string instrument

This is my 3 string instrument called a Triotune. It is similar to a ukulele, guitar, cigar-box guitar, balalaika, or Appalachian dulcimer. This instrument is modular so you can customize and swap out parts to fit your needs. The new headstock was designed by: Pisařovic. This is still a prototype. This is release 2 of my baritone version and since this version uses a 10mm steel rod, it is incompatible with my soprano version that uses a 6mm steel rod.

Sample recording of Beta R1 (Open G): https://soundcloud.com/grhmhome-583373264/baritone-triotune

R3 tuned to open E:
https://on.soundcloud.com/81Ai9

https://on.soundcloud.com/6evdm

How to assemble:

Parts list: 

• Select a neck of your choice. Parts A and B are needed.
• A body of your choice. Use the chromatic body if you want extra frets or universal if you are using something like fretless or diatonic
• A bridge and nut will be needed.
• M1*7 screws for the bridge and nut.
• M4 screws for the neck and body (I used socket head cap screws)
• 10mm x 450mm steel rod for the neck and body
• Filament (I used PLA, but feel free to experiment with other materials)
• Screwdriver
• Hex key if you are using socket head cap screws
• Geared ukulele tuners with screws
• Baritone ukulele strings (feel free to try other types of strings and tunings, but ukulele strings seem to work the best for me)
   

Parts I used (not affiliate links):

https://www.amazon.com/dp/B07Q3GD21V 10mm x 450mm steel rod

https://www.amazon.com/dp/B00EQ2ABD4 Ukulele geared tuning pegs

https://www.amazon.com/dp/B00QXF304E1 Any Baritone ukulele string should work. Use whatever you prefer or experiment with other kinds of strings.

https://www.amazon.com/gp/product/B07GKXMSVR M1 screws

https://www.amazon.com/gp/product/B07HVRJW5J M4 screws

First, you will want to attach the bridge to the body and nut to the neck. Make sure the taller side of the bridge is facing the neck. Do a test fit with all the parts and make sure your tolerances are correct. The steel rod should be able to slide down the neck into the body. Make sure there aren't any zits or stuck on plastic inside any of rod holes. 

Test fit each part separately before you assemble the neck. Once all the parts fit correctly, insert the steel rod all the way down then use the M4 screws for the body and neck. 

Use 3 of the 4 ukulele geared tuning pegs and use the included screws. One will go on the top and two will go on the sides. Use a small screwdriver to make pilot holes then screw the tuning pegs in. I have a picture of the back of the instrument to show which way the tuning pegs should go.

Once everything is assembled, tie on the strings and tune it however you like. I used the G,B,E strings and tuned the E string to D (open G tuning). 

Update: If you use baritone uke strings, I suggest tuning it to GBD if you use the top 3 strings. D-F#-A or E-Ab-B if using the bottom 3 strings. You could just use standard uke tuning too (DGB if lower 3 or GBE if upper 3 strings.) Experiment and have fun.

Feel free to post any criticisms or suggestions for this project.

Update: 6/25/23: I added a fretless neck and a fretless body. Fretless is a lot harder to play, but its there for those who want it.

Update: 6/11/23 Since the contest is over, I've uploaded a .step file with the Soprano and Baritone versions of the Triotune. Feel free to remix.

I have also included a V style body. There are two versions. One is a full size body for those with larger printers and a multipart version for those like me who have a smaller printer. If you use the Mini+ version, just glue the 3 body parts together.

Update: 5/28/23 I added a new body to this instrument. A Balalaika version. Now you can use this instrument as a travel size balalaika. I wonder if someone will experiment with balalaika strings or find strings suitable for tuning to EEA.

Update: 5/25/23 I made the headstock thicker to keep the headstock from flexing.

Update: The Beta R3 version of my baritone Triotune is no longer compatible with my soprano Triotune since I switched to a 10mm x 450mm steel rod. On the plus side, the string action is lower and the instrument is now enjoyable to play. The new body makes the instrument louder.