Dramatically lightened the Y axis carriage, in order to improve dynamic behavior.

Filament support included.

Fixed the problem with the upper left side (the extruder clashed with it), and also the problem of the nut that clashed with Y axis motor.

Modified the distance between the two pieces that make the Y axis tensioner, so as to hold the F624zz bearings with washers. Also, modified the hole diameter.

Y axis now measure 350mm, the extra 9mm are added on the front side.

Y axis bearing holder and Y axis belt holder are replaced by printed parts, as the metalic parts caused troubles.