This is o'cello with 1/2" center rod ( 13mm-ish hole ).
First thanks cokane for the excellent model, I own a electric one but it is rather bulky, and I try to make a compact one in this build.
I used these items:
tube (https://www.amazon.com/Rolled-Steel-Drawn-Mandrel-Tubing/dp/B000H9P4H8?th=1)
rod (https://www.homedepot.com/p/1-4-in-x-36-in-Zinc-Plated-Round-Rod-802297/204273961)
to make the telescoping end pin.
Rubber end pin tip (https://www.amazon.com/gp/product/B075R8PSVS) is used as even ninjaflex is not as grippy as the real rubber tip.
[Edit notice: Amazon seems to stop carrying the 1/2 tube I use. The new link for the tube is of the same spec, but I have not tried tube from this vendor.]
In this build I also made a different part 6 to mount a c-channel holder, which holds two c-channel style shelve stiffener for a telescoping knee brace. The c-channel I have is for 3/4" board.. but I can't find web page for it. So you might need to modify those parts to fit your need.
The tuner I got (https://www.amazon.com/gp/product/B00GGMWD3S) is 14mm in diameter, and I made a version of part 6 to hold it without a screw plug. I printed part 6 with 4 layer wall, and it is holding up fine.
Yet another piece in this build is a folding chest rest, which should also work for normal 12mm build.
For the hand screw style hardware, I use 1/4 hex screw and wing nuts. the rest are the same m5 socket screws, some might be shorter. This assorted screw
(https://www.amazon.com/gp/product/B072LTK9S8/) is what I got, so if you get it you are covered.
Now on to playing cello! I need some better string now!
P.S. Somehow Thingiverse is killing my amazon links when they add their affiliate tags. Copy and paste the URL to view the item.
=====AUG 2020=====
I have not work on this for a while now.. Adding the blender file I used, use it if you wish to mod it further.
| cello_0.5in_design.blend | 4.8MB | |
| ocello_0.5in_part1.stl | 36.5KB | |
| ocello_0.5in_part2.stl | 34.8KB | |
| ocello_0.5in_part3.stl | 28.9KB | |
| ocello_0.5in_part4.stl | 31.3KB | |
| ocello_0.5in_part5.stl | 31.8KB | |
| ocello_0.5in_part6.stl | 59.4KB | |
| ocello_0.5in_part6_14mm_tuner_hole.stl | 85.1KB | |
| ocello_0.5in_telescoping_end_pin_stop.stl | 52.0KB | |
| ocello_c-channel-knee-brace.stl | 50.5KB | |
| ocello_c-channel.stl | 97.2KB | |
| ocello_folding_chest_rest_arm.stl | 114.2KB | |
| ocello_folding_chest_rest_base.stl | 69.8KB |
