This is where I am in the research for building a good, modular, robotic arm system with string pulley mechanics. I use 1/32 in stainless steel cable and aluminum crimpbeads to connect two pulleys.

I recommend printing them in the orientation they are in (even if you're inclined to lay them down ;)

I also recommend printing them without supports though you may need to enable "bridge" settings for the openair gaps.

Download the files from Thingiverse.
https://www.thingiverse.com/thing:648...