Help with printing Ninjaflex

[richb77 0]

HELP!

I need to print a few ruberised bits for work and bought 10M of Ninjaflex.

I cannot get it to print at all! Not even extrude through the nozzle! It just bunches/Stalls in the bowden tube.

Settings are.

Nozzle = 240C

Baseplate = 65C

Feed 110%

Speed 20

Retraction is off.

I stripped the nozzle and completely cleaned it. I can see clear daylight through the extrusion point and it prints perfectly with PLA and ABS.

I cannot figure out why the flex isnt extruding?

:(

[gr5 2,267]

The bowden has high friction with ninjaflex. So get some light petroleum oil such as baby oil, sewing machine oil, 3-in-1 oil. Put some on the filament and slide it into the bowden to get it coated in rubber. Also make sure to cut the tip of the filament to a point to get it down to the nozzle. I found the iRoberti feeder or the "plus" feeder work much better than the original feeder for ninjaflex.

[luukakkerman 0]

Hi all, and future readers,

Oil might help but this is easier for the long run:
** Buy Yourself A PTFE Bowden Tube **

On my UM2+ I have printed NinjaFlex with mixed results a year ago.
Last week I used it again for a new project and had difficulties finding the right settings. Adding 5-10% flow is essential but also on high temp and freshly cleaning (atomic pull) nozzle worked well 1 print, failed the next one etc. Under extrusion from the start or suddenly after quite some layers. With the clean nozzle the only problem could be the feeding. Cleaning the feeder and fresh undented NinjaFlex filament didnt fix it.

So I expected the flex filament being spaghetti in the non-PTFE Ultimaker bowden tube would cause too much friction at those under-extrusion moment. And indeed, sometimes the filament looked to be pushed fairly straight, but often when under good pressure it curled in S-shape/zig-zag like way as the UM bowden inside dimater is larger than the 2.85-3mm filaments.

I read good stories about the lower friction of PTFE tubes. Bought one (from the RepRap guys here in The Netherlands) and after install print was just fine. You also really feel the different in friction when you compare by feeding filaments through both.
The one I bought from RepRap also has a smaller inside diameter I noticed, leaving less room for heavy zig-zag'ing which I think causes the heaviest friction.

Buy yourself one if you have trouble. You need 73cm, they often are sold per 10cm.
Only downside, they are not fully transparent. Translucent to almost solid white. If you really like to see your filament moving or spot dirt in your tube this might be a disadvantage. If not, nothing to loose here.

Good luck guys