Hi all,
just wondered why the flange bearings are of type ZZ instead of 2RS.
As I know, one uses:
open ones, if having high rpm but absolutely no dust
2RS, if low rpm (up to 3000) but dust
ZZ somewhere in between
Currently, there is no problem with mine - all bearings work smoothly, but I think the ZZ type has potential to break. The steppers rpm are low, so why not use type 2RS?
You are correct, the 2RS would probably be a better choice overall. The choice mostly just comes from ease of sourcing, availability, and cost.
As far as I have seen the ZZ type bearings have shown to be functioning fine in the general use of the part, but if I can get 2RS bearings in the future, I will try to use them for future iterations.