Spontaneous filament breaking  

Page 1 / 2
  RSS
Kenn
(@kennd)
Estimable Member

For a while now, I have been confused as to why some jobs stop and ask for a filament change just after the intro line is printed. When I press the knob to unload the filament I discover the filament was broken. This has happened a half dozen time recently.

At first I thought:

  • There might be an issue with the printer, but why always at the same point in the print job?

  • The spool of PLA I am using is sloppily wound (AKA <>ily wound) and has significant bends/kinks in it and would occasionally form a loop as it came off the spool. NOTE: it was not jumping over the edge of the spool. Were the kinks breaking as the extruder tried to pull it in?

I decided to just watch it, use up the remaining filament and see what happened.

I did about a dozen 2-3 hours prints with no more issues... until this morning when I went to do a print and saw the filament was almost completely broken through just above the extruder. The printer was just as it was when the last print job completed.

So, either I have a bad spool or my printer is haunted by little ghosts with tiny knives.

I have had good results from other filaments of the same brand but different 'flavour'.

This topic was modified 1 month ago 2 times by Kenn
Quality is the Journey, not the Destination
MK3S, Nylock mod, Modified Y-axis bearing mounting
Primary CAD program: Trimble Sketchup Make 2017(standalone) with 3D extensions
My limited prints on Prusaprinters.org...
Posted : 26/09/2020 5:58 am
jsw
 jsw
(@jsw)
Prominent Member

Wet filament can be brittle.  You might try drying it in a warm (not hot) electric (not gas) oven or food dehydrator.  PLA that is in good shape should not crack or break easily.

Posted : 26/09/2020 8:06 am
Karl Herbert
(@karl-herbert)
Famed Member
Posted by: @kennd

For a while now, I have been confused as to why some jobs stop and ask for a filament change just after the intro line is printed. When I press the knob to unload the filament I discover the filament was broken. This has happened a half dozen time recently.

At first I thought:

  • There might be an issue with the printer, but why always at the same point in the print job?

  • The spool of PLA I am using is sloppily wound (AKA <>ily wound) and has significant bends/kinks in it and would occasionally form a loop as it came off the spool. NOTE: it was not jumping over the edge of the spool. Were the kinks breaking as the extruder tried to pull it in?

I decided to just watch it, use up the remaining filament and see what happened.

I did about a dozen 2-3 hours prints with no more issues... until this morning when I went to do a print and saw the filament was almost completely broken through just above the extruder. The printer was just as it was when the last print job completed.

So, either I have a bad spool or my printer is haunted by little ghosts with tiny knives.

I have had good results from other filaments of the same brand but different 'flavour'.

The numerous filaments available on the market vary greatly in quality. New does not necessarily mean that it is free of moisture.
I have a dehydrator next to my printer - well, I print a lot of nylon and moisture in the filament is always an issue.

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 26/09/2020 5:20 pm
charles.h13
(@charles-h13)
Famed Member

I have had a couple rolls that kept breaking.  I am not sure why they were so brittle.  

Posted : 26/09/2020 6:31 pm
Karl Herbert
(@karl-herbert)
Famed Member

@charles-h13

When drying in a dehydrator, the temperature should not be too high, otherwise the filament may become brittle. I have also read that the filament loses its "suppleness" over the years.

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 26/09/2020 6:45 pm
bobstro
(@bobstro)
Illustrious Member

I've had 2 brands of PLA deteriorate to the point that bending them in much of a circle at all would cause them to snap. This was particularly a problem if the bed had been raise, then lowered with the filament loaded between prints. In one case, drying helped get through the spool. With one other budget brand I simply abandoned the remaining filament.

My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 27/09/2020 3:56 am
Kenn
(@kennd)
Estimable Member

Thank you all for your thoughts and experiences.

Normally I leave my PLA on the printer for up to two weeks when I am in printing mode. For a year and a half, in my environment it has never been an issue. Complacent? This PLA was supposed to be more flexible and tougher that their previous (discontinued) PLA. I wonder if filament manufacturers have come done with "smartphone syndrome", where they rush to release something new to market. I bought a spool of their new PETG that is supposed to print at with PLA settings. Should be interesting when I get around to experimenting with it.

I do not have or use a dehydrator. When I take a spool off, I put it in a weatherproof container with a 4 pound tub of desiccant. The last spool has been in there for over a month now. 🙂 

Time to do some hands on investigation.

Quality is the Journey, not the Destination
MK3S, Nylock mod, Modified Y-axis bearing mounting
Primary CAD program: Trimble Sketchup Make 2017(standalone) with 3D extensions
My limited prints on Prusaprinters.org...
Posted : 27/09/2020 4:55 am
bobstro
(@bobstro)
Illustrious Member
Posted by: @kennd

[...] Normally I leave my PLA on the printer for up to two weeks when I am in printing mode. For a year and a half, in my environment it has never been an issue.

It's also very dependent on your local environmental conditions. My first spool of PLA that wasn't sourced from Prusa was Paramount. I really like their stuff. I've printed many spools of their PLA. Over the course of 3 days last Christmas break, I went from minor, gossamer stringing to a ridiculous spider's nest. Fortunately, drying restored it sufficiently to finish the spool off. The spool of PLA that started snapping had also been fine for months.

Look into a dehydrator long term. Your filament can't be too dry (within reason) and it's always nice to be able to eliminate moisture absorption as an issue. Dry bags and boxes are good for storage, but can't dry saturated filament sufficiently.

My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 27/09/2020 5:11 am
Kenn
(@kennd)
Estimable Member

Maybe when/if I graduate to more advanced filaments. Right now, quarantine for extended periods of time in drybox will have to do. I only have room for 1 more machine, and I had to decide between another printer or a drybox.  Hard choice. I will live with some breakage. Canadian Authorized Prusa dealer has about 50 in stock right now.

If I expected perfection and no little bumps like filament breaks at random, I would have taken up a different hobby.

Quality is the Journey, not the Destination
MK3S, Nylock mod, Modified Y-axis bearing mounting
Primary CAD program: Trimble Sketchup Make 2017(standalone) with 3D extensions
My limited prints on Prusaprinters.org...
Posted : 27/09/2020 8:00 am
charles.h13
(@charles-h13)
Famed Member

@karl-herbert

good to know.  These came from the manufacturer that way.  

Posted : 27/09/2020 11:26 am
Karl Herbert
(@karl-herbert)
Famed Member

@charles-h13

For this reason I only buy filament and nozzles for the Prusa from brand manufacturers, because you can save yourself a lot of trouble. Cheaply bought is often more expensive.

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 27/09/2020 4:36 pm
Kenn
(@kennd)
Estimable Member

This is not a 'cheap' filament. It is from a manufacturer that I have grown to trust, just as everyone has a brand they trust, but most know that things can change from spool to spool or even from one day to the next.

Of all the things that could go wrong (blobs, spaghetti, poor bed adhesion, layer shift, etc.), a filament breaking on a machine where the filament sensor HAS NOT been disabled and is working is like an itchy nose - irritating, but easy to deal with.

What was interesting in my case was when, and where the break happened. Always at the beginning of a job after sitting idle for a day or so. Always near where the filament enters the extruder. Never in the middle of a job.

I have purposely not mentioned the brand as I have not followed up with them. They are responsive to reasonable requests like when I explained how I thought their customers would benefit from having the approx. weight of the empty spool printed on the spool. It is now on the spool label. This why. Respect! Give it and you will receive it.

Kenn

 

 

 

Quality is the Journey, not the Destination
MK3S, Nylock mod, Modified Y-axis bearing mounting
Primary CAD program: Trimble Sketchup Make 2017(standalone) with 3D extensions
My limited prints on Prusaprinters.org...
Posted : 28/09/2020 12:42 am
charles.h13
(@charles-h13)
Famed Member

@kennd

Same here.  My filament was not cheap.  They replace the whole spool after I sent them videos showing how brittle it was.  

Posted : 28/09/2020 1:20 am
Karl Herbert
(@karl-herbert)
Famed Member

This is the advantage of buying from brand manufacturers. Defective goods are replaced and the support is usually appropriate.

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 28/09/2020 1:48 pm
charles.h13
(@charles-h13)
Famed Member

@karl-herbert

Concur.  The manufacturer, who will not be named, makes a huge number of filaments.  They are of high quality and this roll of PLA was just terrible.  I texted them and all they asked was to see a cell video of it breaking.  It broke with a 30-60 degree flex.  They replaced the roll and sent me a box of samples.    

Posted : 28/09/2020 2:31 pm
Karl Herbert
(@karl-herbert)
Famed Member

@charles-h13

Could the manufacturer say anything about the causes of the brittle filament? Maybe a bad alloy, too much heat during production or too much moisture ?
Would be interesting to know...

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 28/09/2020 2:42 pm
charles.h13
(@charles-h13)
Famed Member

@karl-herbert

I did receive an email from them a few days later saying the recalled the lot.  No other specifics.  

Posted : 28/09/2020 5:22 pm
Karl Herbert
(@karl-herbert)
Famed Member

@charles-h13

I think it was a bad charge. That can happen anywhere now and then. If the manufacturer calls them back, this is not a problem. I've always been lucky so far and have never had a problem in this regard.

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 28/09/2020 6:49 pm
charles.h13
(@charles-h13)
Famed Member

@karl-herbert

I may have been the first to report it and initiate the recall. Who knows?  

Posted : 28/09/2020 6:53 pm
Karl Herbert
(@karl-herbert)
Famed Member

@charles-h13

Some people call me crazy because I buy 1kg PETG for 40 Euros. I've printed tons of faceshields with it without incident and the things are extremely stable. I have invested a lot of money in the printer and I don't want to save on these components (nozzles and filament). I like to compare this with car tires. Expensive car and cheap tires do not go together.
But as always, everyone has his own opinion.

Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen....
Posted : 28/09/2020 7:51 pm
Page 1 / 2
Share:

Please Login or Register