Sunlu S4 modified spool holder

As the Bowden tube from my Sunlu S4 is quite long (about 1.2m) and combined with the drag on the spool stock mounting causing issues with the extruder slipping on occasion I looked at a way to eliminate the friction on the spool holder. With the rollers now fitted to a “stand off” and the spool rolling on both shafts from the top the drag is almost zero now, no more extruder slipping. Been running it for a few months now to prove it (even with TPU) i have had no issues at all with the extruder slipping.

There are 2 versions, version 1 is simple and version 2 has a triangular cross beam between each riser for more stability, not to say I've had stability issues with version 1. Version 2 is a recent mod / upgrade.

The rectangular extensions on the leg ends fit into the slots below the original bearing bracket to keep the legs in place. The End Covers can be glued on but if XY compensation on the posts is done when slicing they can be made to fit tight and be pressed in, which is what I have done. No supports required on all parts.

Hope the change is found to be useful.