The O'Cello is a 3D-printable cello developed by Conor O'Kane, which is free to download and print for personal use.

Update: November 23rd, 2016 - new version - This updated version now includes chest and knee rests for supporting the O'Cello while playing, and an adjustable end-pin. This is no longer a prototype, it is now ready for anyone to print and play.

All the components for an O'Cello can be printed on a 20cm print bed.

Inspired by the design of the F-F-Fiddle, the O'Cello incorporates a 12mm diameter steel rod running through all six major parts to provide rigidity.

Parts list
The following parts are needed to build an O'Cello:

M5x45mm socket head cap screws: 7
M5x30mm socket head cap screws: 2
M5 nuts: 9
M5 washers: 12
12mm diameter steel rod, 1m length: 1
10mm diameter aluminum tube, 45cm length: 1
Aluminium L-bar, 20x20x2mm, 30cm length: 1
Cello Strings: 4 – (1 of each C, G, D and A strings)
Bass guitar tuning keys: 4 – (2 left and 2 right)
25mm screw plugs
About half of a 1Kg spool of 3D printer filament. The O'Cello pictured here is made with PLA, but ABS should work fine.
Recommended sources for many of these parts can be found in the Complete Assembly Instructions PDF.

The O'Cello does not need sanding or painting after printing. It is ready-to-play once printed and assembled.

Thanks to Dan Michitsch for his invaluable input on the design of the knee and chest rest parts.

Check out his performance on the O'Cello here... https://www.youtube.com/watch?v=lSVwg5sikZ4