Neat trick for Bowden upgrades

I ran this print on my Ultimaker, but I know at least a few of you have converted your Robos over to Bowden as well, so I thought I'd share. I've been playing around with cutting filament into little 2-3" lengths and filling up the bowden tube. Last night I decided to try it with different materials and got a pretty cool effect.



This was done with mixed lengths of colorFabb PLA/PHA in Dutch orange and magenta with NinjaFlex for the black. I used a 0.8mm nozzle with 0.3mm layer height. When printed in straight PLA, the bracelet is pretty stiff. In this configuration, you get some really nice flexibility. The bond between the PLA/PHA and Ninja Flex is quite weak, and you can see that the profiles for the two materials are different so you get some weirdness as one material runs into the next. However, still a really neat effect and worth further investigation.

You can do all of this with a direct drive extruder as well using filament changes at z-heights, however this Bowden method has some unique advantages. One is that the filament changes are automated. Another is that it really helps feed the soft Ninja Flex through. Rather than having a long length of floppy Ninja Flex to push, you have short pieces sandwiched between the hard PLA/PHA chunks.

I'm working on a more involved write up on this using other material combinations (going between PLA and wood is really awesome) and will update when it is done.

 

Very cool how are get them to feed correctly into the hotend sometimes the transition from the PTFE tubing to the hot end can be tricky