Space Pi4 improved Bowden connection V2

Previous model worked but had some failures, mostly after drying cycles on the space pi. Also, I was not able to remove the 3 inserts left (without risk of damage), so I redesigned to adapter to better fit my needs.

I kept the original design because I think it can still be handy, with some modifications.

This redesign is meant to be used in combination with the SpacePi 4 inserts but also works if they are removed.

In my own experience (I am using it on all 4 positions), I've seen no issues after drying cycles (incl. ASA and ABS) nor pushing/pulling filament to the printer.

In this revised design, I changed some aspects:

• The long tube (in outer piece2) is placed from outside (back side) inwards. This makes it much easier to place. It is gripped be the inserts, if present. Can be pushed in, to remove need to push on the insert plastic ring.

• It also has an opening to allow to push down the insert plastic ring, and remove it.

• on the inner side, the tube (outer piece2) is gripped by pressing the 3 blades in "inner grip". This is achieved by rotating the "lock ring" about 30 degrees over it.

• The "inner grip" also provides guidance to insert filament.

Notes:

• if you want a minimalist design, you can skip the "inner grip" and "lock ring" (the parts mounted on the inner side). Only loose the filament guiding into the tube, but the original inserts must be in place to grip the tube.

• I made protos in PETG (grey parts, older) and ABS (black parts, latest) and the best results were with ABS. PETG had some broken "inner grip" while locking.

Printing tips:

Nozzle: 0.4mm

Layer height: 0.2mm (0.12mm for better quality in small details)

Infill 45% for strength

Supports only needed/recommended on the outer piece 2, as shown below