Z axis top brackets, of P3Steel, differ between v1.x/2.x and v4 I have been studying the differences between version 2.x and version 4 of the P3Steel frames - in particular the AC08 bracket at the top of the frame which secures the top of the smooth bars and threaded rods of the Z axis on both the left and right sides. Here is the laser cut parts, for version 1.x, showing the part labelled as AC08:



Version 1.x/2.x has the AC08 bracket with two holes, one for the threaded rod and one for the top of the smooth bar (from the lasercut image):



However, in version 4, the corresponding top Z axis bracket only has one hole for the smooth bar and just an indentation for the bearing which holds the top of the threaded rod (from Twitter):



Here is a close up of the diagram from the google docs repository, listed in the v4 section on the RepRap Wiki page for the P3Steel, which shows the bearing assembly just apparently "resting" against the indentation:



Here is the bracket shown with the bar and threaded rod (again, from google docs):



Does anyone know why the top of the threaded rod is not secured by a hole, as it was in version 1.x/2.x? It just does not look particularly well secured.

Under the list of version 4 changes, see 2. Frame versions, it is mentioned:


  The extruder no longer hits the Z axis top bracket


Is this the reason why the change has been made?
I've just seen this right now, I'm Alvaro Rey, the designer of the p3steel v4 mod. The change was made, because with previous versions with the extruder homed, if you go up in the Z axis, the extruder motor could hit the Z axis top plate. So, in order to avoid that, I just changed the design.

The bearing in the z axis is not necessary but some people prefer to use it, in order to avoid wobble in the threaded rod. 

Anyways, I designed a printer part to fix the bearing in the Z top plate.