Really, best of luck with your project. I think a 3D printed robot arm is very achievable with a bit of dedication and patience, but obviously it will be very limited in terms of the weight/forces it can handle compared to its metal counterparts.
Nonetheless, I think it is a very excellent project to take on.
Here a few more links…
There’s @jlauer whose robot arm has featured on our forums: https://community.simplefoc.com/t/3d-printed-robot-arm-acceleration-deceleration-planner-algorithm/958/16
If you’re not familiar with Skyentific’s excellent YouTube channel, you should take a look…
https://www.youtube.com/c/Skyentific
→ after watching a few of his videos on how to make robot arm actuators, you’ll have no further questions 
There’s Peter Crnjak’s arms: Petar Crnjak's Profile | Hackaday.io
and many more on hackaday