My Ultimaker 2+ grinds a filament!

[kunitsa 0]

Hello dear friends.

I really need in your help.

My Ultimaker 2+ permanently grinds a filament!

I've tried already many things to solve this problem: I played with feeder tension, with retraction settings with temperature settings. Nothing.

I would be very grateful if you could advise me anything.

Thank you in advance.

V.

[Smithy 1,146]

There must be a reason why the filament cannot pushed forward or not as it should. So check your TFM coupler if it is ok or not, this is probably the reason. Or your Bowden tube is old and needs to be replaced. Or a completely clogged nozzle, but then you would have more problems.

 

Test your TFM coupler if you can push a filament manually trough the tube. Unscrew the nozzle or take out the bowden on the print head and try if you can move a piece of filament in the head without much friction.

Edited November 5, 2018 by Smithy
Typos

[kunitsa 0]

Thank you very much, Smithy! Now try to do all these things. Truth be told, the printer prints from time to time without problems. Could this dragging be somehow related to the print settings (retraction settings), or problem with improper heating of the extruder? 

[Smithy 1,146]

Retraction yes and no ? Of course a lot of retractions an the same spot of filament will grid the filament, but unless you print an object with a lot of retractions, I don't think so. The default retractions settings in Cura of normally ok. (There is a setting to say, how many retractions should be done max. on the filament, to avoid a grinding)

 

Improper heating of the extruder can also be a problem, but I assumed you heated the nozzle the temp you need for your material. But yes, if the nozzle is not hot enough, the filament cannot pushed through the nozzle and the feeder grinds the material.

 

But check the coupler first, here are some instructions to change, but you see what I mean.

[kunitsa 0]

Dear Smithy, 

sorry for the trouble and for having to ask you again for help.
Since our last communication, I did everything that you advised to determine the cause of the problem.
I disassembled the extruder, cleared the nozzle by the atomic method. The TFM couple and bowden tube seem fine. 
After disassembling and cleaning the feeder, the result is the same: the printer grinds the filament arbitrarily, even on the first layer.

I do not know what to think. I bought this printer instead of my previous BQ Hephestos 2 Prusa and it seemed like it should print out of the box.
Maybe the solution would be to put a mechanism from DDG from Bondech for U2 +?

I will be very grateful if you give me any other advice.
Thank you in advance. 

[Smithy 1,146]

Can you post a picture of the grinded filament?

[kunitsa 0]

Dear Smithy,

thank you very much for your reply. 

This is not a new photo but I made it a few month ago. There was the same probleme. 

[Smithy 1,146]

Ok, if you have checked everything in the hot end and there is everything fine, you could try to dismount the bowden tube at the feeder side, pull it out, heat you nozzle and try to push the filament manually through the tube. It should be easy to do that. With this test you can check if really everything is fine around your print head.

 

Another possibility could be, that your feeder tension is too high, check this also. Or that the knurled wheel of the feeder is worn out and cannot grab the material as it should.

[Smithy 1,146]

And do you have this problem with every filament? Can you try another spool?

[kunitsa 0]

Dear Smithy, 

As for the feeder tention, I can honestly say that I have tried all the options of pressure, from strong to its complete lack.

 

I use only ColorFabb and Ultimaker PLA filaments. This problem exists with any filament.

 

Just in case I would like to show you a photo of TFT coupler.

 

Thank you very much.

[Smithy 1,146]

The coupler looks good to me.

Good question, I am near the end of more ideas......

[geert_2 558]

Is the bowden tube installed correctly (=wider opening at feeder)?

 

If the feeder wheel would be okay (=not covered in plastic, and teeth not grinded away), and the nozzle is okay, and the bowden-tube is okay, maybe it could be the sum of friction in the whole feeding traject that is too high. Then you need to examine each part of the traject for friction or blockings.

 

Also, I vaguely remember someone else where something was broken in the feeder, causing issues.

 

[kunitsa 0]

Thank you very much.

 

I already doubt that the printer can ideally print well. Can we still put the DDG extruder from Bondech instead of the native feeder to ensure the forced filing of the filament?

[Smithy 1,146]

15 minutes ago, kunitsa said:

Can we still put the DDG extruder from Bondech instead of the native feeder to ensure the forced filing of the filament?

 

If your problem is somewhere after the feeder then it will not help.

How old is your Bowden tube?

 

And have you checked this:

4 hours ago, Smithy said:

you could try to dismount the bowden tube at the feeder side, pull it out, heat you nozzle and try to push the filament manually through the tube. It should be easy to do that. With this test you can check if really everything is fine around your print head.

 

[kunitsa 0]

My U2+ is 1,2 years old and about 600 hours of printing time. 

I never changed the bowden tube.

[geert_2 558]

I think it is best to test all parts of the whole feeder traject *separately* first, to determine *where* the problem is, before changing parts.

 

I would suggest: disconnect the bowden tube at both ends. Remove the filament from the printer, but leave the spool on the printer.

 

Then step by step:

- Try to manually unwind filament from the spool. Does it go smooth, almost without resistance? Sometimes filament windings may get stuck under each other.

- Feed a piece of filament manually into the bowden tube (with tube disconnected at both ends). Does it go smooth, almost without resistance? If there would be kinks in the filament, or a too thight bending radius, this might cause a huge amount of friction.

- Heat up the nozzle to the correct temp for that material. Manually feed filament into it (=directly into the nozzle, without bowden tube). Do you get a thick nice flow, without having to apply too much pressure? Keep pushing for some time, a few minutes. Does it keep going well.

- Using the "Move Material" function of the printer, feed a piece of filament through the feeder (=without bowden tube, only the feeder). Does that go well? Try to pull on the filament, or try to keep the filament from moving, while you use the "Move Material" function, and see if it slips too soon? If I remember well, user gr5 said that the feeder should be able to lift the whole printer, whithout the feeder slipping?

 

Try something along this line. Somewhere something in this traject must be out of spec.

 

Or it could be a combination, e.g. partially blocked nozzle, worn out coupler (its color looks okay in the photo, but it is hard to see if there are dents on the inside), worn out bowden tube, worn out feeder (e.g. if used for abrasive materials), kinks in filament, filament mangled on spool or a too tight bending radius near the end of the spool. So the sum could be too much.

 

[kunitsa 0]

Dear Geert,

Many thanks for your help. Finally, a few months later I corrected the problem thanks to your advice.
Thank you so much
Have a nice day

:)

[KramE 0]

What was your solution? 

[kunitsa 0]

My solution was to replace the TFM coupler and bowden tube.
To be honest, I ended up completely replacing my native feeder with a Bondtech DDG. Something like this...