NinjaFlex Filament : new Extruder design?


Does anyone have any ideas on the best way to print ninjaflex using the mbot grid II?

I made the experience, that the Extruder is creating some issues because the Filament is to flexible and is “leaking” out before be extruded into the nozzel… Like there is to much resistance before entering the nozzel.

Has anyone changed the design of the Extruder, so that no Filament is able to “get out” of the path to the nozzel after being pushed?

That would be a nice update!

Any news here?

Would it be possible to have a new design of the Extruder so any Filament is more guided to the nozzle?


I am considering using NinjaFlex with the MBot Cube. Can you please share your experience with varying temperature, retraction, and speed? For me, tweaking variables is more appealing than building a new extruder, and I’m hoping that there is a combination that will work with the existing one. Thanks!

I’ve not started to print any object up to now because I wanted first to have the Filament flow for a while through the extuder.
The result: after 10s, the Filament can’t be pushed anymore into the Extruder and by-pass the guiding/pressing device.

In fact, the Extruder is ok (if we talk about the heated square). But the device Close to the Motor has an issue. It works as Long as your Filament is “strong” as PLA. But NinjaFlex is already flexible and Need better guidance before entering into the Extruder (or its heated nozzle).


OK, so I am ignorant of much, but I was imagining that maybe you could compensate for this problem by increasing the extrusion temperature? According to the manufacturer, you can extrude at up to 225 degrees.

It doesn’t say if the viscosity is higher at higher temp or not. And that is the isse here: the viscosity is creating a higher backpressure on the Filament, which can’t be pushed towards the Extruder. Therefor, there is a Need for a better guidance. Which in fact could even help with PLA (when adding a strong spring).
My 2.5 Cents… and no words about ignorance;-)

I assumed that increased temperature would decrease viscosity, but that is only an assumption. I did see this mod yesterday, which may apply to your need:

Also this:

When you start to print the Grid II always travels to the front left corner of the x and y axis which is kinda dumb but that’s what it does. So I always put a 1/4 inch .010 thousands thick pad in my prints in the left front corner of the build plate. Doing that makes the extruder start printing there and it cleans up the start strings and also gives a chance to see how it’s flowing before it gets to the main part of the print.

I done flexible filament print,watch this video

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