This is a design of y-axis bushings without gluing.
With glue it is a mess to change or to remove the bushings.
Now at least the y-axis can be changed without removing the glued PLA bushings.
For this you have to drill holes into the y-axis-bottom-plate.
How to do this is described on: www.ifeelbeta.de
If you don't have a 3D printer yet you can order some at: www.2printbeta.de
A short foto story about how to install these bushings can be found at: www.ifeelbeta.de