Underextrusion? Understatement!

[VVPD 0]

Hi All,

I hope someone can help me with this. I have an Ultimaker 2, on which I am trying to print using NinjaFlex. I know that this is not the best feeder for it, but this is the printer I have and I need the rubber components. Now, I have tried everything:

Nozzle temps between 210 and 250 degrees

Bed temps from very low to 90 degrees

Increasing fill level and decreasing it (between 20% and 65%)

Layer height around 0.1mm

Print speed of 20-25mm/s

Outer shell speeds of around 40mm/s (1.8mm3/sec) - so very slow

Toggled speeds between 90% and 105%

toggled flow between 95% and 110%

I attached a picture of the standard calibration part. It looks really pretty, like coral. But it is not exactly right. [/media]:angry:

Does anyone have some good advise on how to get the prints out right?

[SandervG 1,521]

Hi @VVPD, welcome to the forums!

Do you have any modifications on your Ultimaker 2 or is it the complete stock set up?

What I would first like you to do is during the print, see if the flexible filament is not getting tangled up in the feeder.

Next, add 2 drops (not more!) of sewing machine oil in the bowden tube (detach from the back, hold it straight up and down the hatch they go!), disable retractions and increase the tension in the feeder a little bit.

Print around 15/20mm/s at 225ºC.

Let me know how that goes

You have to play around with the settings a little bit, but it certainly is doable. I have printed (among others) an entire enable hand with NinjaFlex so I know from first hand experience.

[DidierKlein 729]

Also make sure you keep a constant speed (have the print speed set to 15 - 20 and the others to 0) and put 0 in minimal layer time to avoid automatic slow down of printing.

Ninjaflex is hard to print but possible

[VVPD 0]

Hi Sander,

Thanks for your reply. We have a few ABS prints we need to get out right now, but I think I will get around to having a new go later this week. I haven't changed anything about the printer, this is the way it came out of the box. I did update the firmware. The only time the filament gets tangled or stuck is during the back-spooling when I change the material. It comes out of the feeder in 6 loops or so, so now I just cut it in the bowden tube, before I spool it back. It's a bit of a waste of material, but a lot less work getting it out.

Do I need to "hit" the filament with the oil? Or is it all about lubrication near the nozzle and can I send it down the side of the tube?

Thanks,

Laura

[VVPD 0]

Hi Didier,

Thanks for commenting!

I have had the speeds very low, but varying between the different stages of printing (as recommended in Cura). I will try a constant speed, How does changing the speed effect the print in general?

Laura

 

Also make sure you keep a constant speed (have the print speed set to 15 - 20 and the others to 0) and put 0 in minimal layer time to avoid automatic slow down of printing.

Ninjaflex is hard to print but possible

 

[yellowshark 153]

Hi @VVPD, this is not answering the specific question you have asked Didier but generally speaking, with PLA, keeping all the print speeds the same will help to give you a higher quality print; it does depend on the size/geometry of the piece you are printing. I am happy to say in front of the Cura people that the defaults in Cura, in this respect, are a bit naughty! 8)