if you can get these you can modify the files for you. I got the 9mm balls from aliexpress but they are no longer available.
printed balls wont work because they will never be perfectly spherical.
one more way is you could try normal 9mm ball bearings and glue them to a socket fixed to the cf rod.
ebay
printed balls wont work because they will never be perfectly spherical.
one more way is you could try normal 9mm ball bearings and glue them to a socket fixed to the cf rod.
ebay