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The O'Cello, a 3D-printed cello
Image: conorokane via Thingiverse, CC BY-NC 4.0
Strings · Cello

The O'Cello

A full 3D-printable cello built around a steel rod; every part fits a 20 cm bed

Designed by conorokane, published on Thingiverse

CC BY-NC 4.0 No commercial use Build info 4/5

Licence verified on Thingiverse, 20 October 2026.

Get the files on Thingiverse ↗ Watch the video
Strings
Standard cello strings (C, G, D, A)
Backbone
12 mm steel rod through all six main parts
Filament
About half a 1 kg spool (PLA shown; ABS should work)
Finishing
No sanding or painting needed
Licence
CC BY-NC 4.0 (personal use)
On Thingiverse
1,522 likes · 254 comments (as of 20 Oct 2026)

About the O'Cello

The O'Cello is one of the best-known printed string instruments: a playable, electric-style cello whose printed parts all fit on a 20 cm bed. Its open, skeletal body gets its strength from a 12 mm steel rod threaded through all six main printed sections. An aluminium tube and angle bar add the rest of the structure, and bass guitar tuning keys hold standard cello strings.

Later updates added chest and knee rests, developed with a cellist who performs on it in the first video below, plus an adjustable end-pin. The walls of the head piece were also thinned to make the tuners easier to fit. The original Blender file is available too, with the parts in their assembled positions to make remixing easier. Popular remixes include a half-inch bar version with folding rests, a traditional scroll top and a printed 'O' badge for the front.

Expect about half a kilo of filament. A complete Assembly Instructions PDF, with recommended parts suppliers, is included in the download.

Who it's for. Cellists who want an affordable second instrument, and makers ready for a big but well-trodden project. A second video shows another maker's time-lapse of printing one of the parts.

What you'll need

Printed parts

  • Six main body parts
  • Chest rest, knee rest and adjustable end-pin parts

Bought parts

  • 12 mm steel rod, 1 m
  • 10 mm aluminium tube, 45 cm
  • Aluminium angle, 20 × 20 × 2 mm, 30 cm
  • 7 × M5 × 45 and 2 × M5 × 30 socket cap screws, 9 M5 nuts and 12 washers
  • 4 cello strings (C, G, D, A)
  • 4 bass guitar tuning keys (2 left, 2 right)
  • 25 mm screw plugs

Tools

  • A saw for the rod, tube and angle bar
  • A printer with a 20 cm bed

Build overview

The full Assembly Instructions PDF is in the Thingiverse download. In outline:

  1. Print the parts. All fit on a 20 cm bed and are oriented flat-side down.
  2. Cut the metal. Cut the steel rod, aluminium tube and angle to length.
  3. Assemble the body. Thread the six main parts onto the steel rod and bolt them together.
  4. Fit the rests and end-pin. Add the chest rest, knee rest and adjustable end-pin.
  5. String it. Fit the tuning keys and strings, then tune.

Print settings

  • Material: PLA (ABS should also work)
  • Filament: About 500 g
  • ? Other settings: See the Assembly Instructions PDF

Videos

Play video: O'Cello performance (loads YouTube)
O'Cello performance, Dan Michitsch (the cellist who co-designed the rests). Plays from youtube-nocookie.com after you click.
Play video: Time-lapse of printing part 5 (loads YouTube)
Time-lapse of printing part 5, George Juszynski (another maker, not the designer). Plays from youtube-nocookie.com after you click.

Nothing loads from YouTube until you press play. Video thumbnails are © their creators.

Photos

Thingiverse doesn't let us fetch its gallery, so the photos stay on Thingiverse. See them on Thingiverse ↗

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