broken filaments

[carminati 0]

Hi everyone, 

 

I have a problem with filaments that broke in the feeders. In the attached file you can see different filaments (pla and pva) with this kind of problem. 

Do you have any advice about it? I try to loosen the screw, connected to the spring (in the feeder's box, back of the Ultimaker S5), but I got poor results. 

 

[NBull 14]

From the picture I'm pretty sure it's you feeder that's grinding the filament til it breaks. as you also mention youself, its most likely that its your feeder tension thats to high. whats the posision at now? It can be other things too.

 

If using a polybox there can be to mutch friktion for the feeder to pull the filament freely. try and print without, and see it it helps.

 

There can be a small plug in the print head making too mutch resistance. try and make hot pull, cold pull til its clean. or change to another core.

 

Your Pla and Pva can be moist, making it to soft. try and dry it. 🙂

 

[DidierKlein 729]

Yes i agree with @NBull and if the filament is being grinded it must be because it's blocked somewhere (either before the feeder or after the feeder), might be a partially clogged core.

 

With PVA moisture ca also give some pretty bad extrusion and add a lot of friction in the bowden for example...

[carminati 0]

In the attached file you can see the current position of the spring in the feeder. 

I try to print and i can still notice a lack of filament's portion (not so bad as the filament in the image above). 

 

I do not use any polybox and i clean the core frequently. 

 

[Smithy 1,146]

Turn the screw back that the indicator is in the middle position, which is fine for 99% of materials.

 

Do you print maybe too fast?

 

[NBull 14]

I agree with Smithy the center position is most the times the best position. if using a realy hard filament more tension is somtimes needed. and if using fragial PVA less. but yes 99% of the time stick to 1/2 tension.

 

If you havn't don it already I would recommend opening the feeder and cleaning the inside. When the feeder have grinded the filament a couple of times a lot of debris can accumulate in the "box" and on the tooth wheel making it to slippery.

ps. rember to losen the feeder befor opening, so the spring don't pop out 🙂

 

You may aslo want to check if you can frealy push PLA through the core. the core can be clean but still have to much resistance. 

 

Also check the bowden tube. it might have a bend making to much resistance or be damaged on the inside. Take some filament and try pushing it through the tube to see if theres a spot whit more resistance.

 

As Smithy mentioned it can also be your print settings, if trying to push too much filament out at to low a temperature.

[carminati 0]

I kept both cores and feeders clean. 

Generally i use the recommended print settings for all the filaments that i extruded. 

 

Now i will try to put back to 1/2 the tension of the spring. I don't understand what i need to do with PVA filament in terms of tension of spring in the feeder. 

[Smithy 1,146]

5 minutes ago, carminati said:

I don't understand what i need to do with PVA filament in terms of tension of spring in the feeder. 

Normally nothing, I print not so often with PVA, but when I don't touch the tension of the feeder. 

But if you get problems with PVA, it could be that you need a little bit less tension, because PVA is softer than PLA for example. 

 

But I don't believe that the spring tension was your problem, so there must be something else. Please follow the advises from @NBull and check also the Bowden tube and try if you can easily manually extrude some filament. 

 

Another idea: Was this failed print, a print with a lot of retractions? Because when you have too much retractions this could also cause the grind in the filament. 

[NBull 14]

15 minutes ago, carminati said:

I kept both cores and feeders clean. 

 

You can still have a clean core thats not good. I am not 100% on this, but i think its something whit the coading inside the core that can get damaged. it will still look clean but have to much resistance.

 

 

15 minutes ago, carminati said:

Generally i use the recommended print settings for all the filaments that i extruded. 

 

If using standart Cura Profiles/ settings you shoulden have a problem whit the flow reatio. so don't worry about this.

 

 

16 minutes ago, carminati said:

I don't understand what i need to do with PVA filament in terms of tension of spring in the feeder. 

 

It is the same with PVA, 1/2 tension is most the time the best solution.

 

If using off brand PVA there can be some differences. 
eg. I run a sligtly losser grip on PVA from Prima and a bit tighter on 3DE-filament. I think they run better this way, but they will still run whit out problems at 1/2 tension.

 

If using an old PVA you can also lossen the tension a bit becors it get a bit more brital whit age, like people 😉

[carminati 0]

9 minutes ago, Smithy said:

Another idea: Was this failed print, a print with a lot of retractions? Because when you have too much retractions this could also cause the grind in the filament. 

To be honest, i've never thought about the retraction speed and so on. I'll definitely check it out