Square bearing guide v1

This is my first attempt at a linear motion bearing guide for 1" aluminum square tubing and will hopefully soon become a part of one very cheap 3d printer. There is more to come please feel free to let me know what you think could be improved in the design. This is also my first thingy so i apologize for any newbie mistakes i might have made.

The bearings that i will be using are 1" flange bearings and are 1/4" thick. The holes are designed to loosely fit a 1/4" threaded rod. If the thingy w