PVA stops extruding about 5 min. after a perfect start

[Harry Plotter 3]

Hello to all of you!

 

Nowadays I encounter a problem I haven´t had so far.

 

Recently I printed 2 prints with natural CPE with a support of PVA. Unfortunately in both prints the PVA suddenly stops extruding.

 

After a thorough cleaning of the nozzle, the Feeder and the filament rests surrounding the nozzles outer rim, I retried the print.. the first one "survived" because the important support survived the nozzle print-time before the filament extrusion came to a full stop.

 

The second print requires 100% support but I can not seem to detect the problem. The outcome is always the same. After 5-6 mins. the extrusion goes from perfect to low quality and the eventually stops. Filament is then grinded and stuck in the BB-Core. After heating the Core to 240 degrees. I can manage to manually deblock the nozzle, by pushing the filament into the nozzle by my hands. The first seconds are hard then the filament extrudes ok and the nozzle works again (like I said for 5-6 minutes)...

 

What in h.. is wrong? I haven´t changed a lot since my last prints. But even if I did I never had that result. I tried on default system entries and on custom. Both seem to show the same problem. Could it bee a general problem with the core? I use it already for 1 year although I do not print regularly. The last print was 3 month ago...

 

I will leave you with a timlapse of the video. I took it too late but you will see what I meen once you will see the print...

 

Hope you have some ideas what is wrong with the nozzle (or the feeder).

 

See you

 

 

Daniel

 

PS: the converted mp4-File to .gif didn´t load up either (what a stupid day)... so now I zipped it for you to see it (if you want to download it and unzipp it...) ;O)

gl450halterung.zip

Edited July 3, 2018 by Harry Plotter

[Dim3nsioneer 558]

The PVA might have picked up humidity. Is it sizzling during extrusion? If yes, it certainly has.

Then you would need to dry the filament.

Another thing you might want to check is your feeder. If it grinded the filament due to a clog, you need to clean it; otherwise it will just grind the material again.

[Harry Plotter 3]

Hi Dim3nsioneer,

 

thank you for your reply...

 

1. The PVA might have picked up humidity. Is it sizzling during extrusion?  NO... it extrudes normally

 

2. I opened the feeder completely the last time but this print failed completely as you can see in the attachment (zipped File)..

 

BUT, I recognized the day that I made this print that the feeder did not advance the filament enough for it to print out the first "blob" before going to printing the brim... so I helped the filament very fast with unlocking the feeder suspensiton and pushing in the filament manually.. then it worked. So it should be an issue with the feeder I suppose. I will look in it again and send you in some fotos. Can it be that the feeder "didn´t get the info" sometimes from the hardware to advance and retract?

Always when I have this problem the filament inside the tube looks a little pushed but if I push it with my hands manually the flow is restored after a while and it runs normally so the pressure shouldn´t be a problem but the feeding...

 

I will send in some fotos later that day.

 

Greetings

 

Daniel

[DF-Werkzeugservice 9]

I'm not really familiar with printing PVA, but I've had similar issues with other filaments. Setting an extra prime amount after retraction solved it! Especially with support materials I prefer having a little blob at the beginning after the retraction than suffering from underextrusion midprint.

[Dim3nsioneer 558]

1 hour ago, Harry Plotter said:

BUT, I recognized the day that I made this print that the feeder did not advance the filament enough for it to print out the first "blob" before going to printing the brim... so I helped the filament very fast with unlocking the feeder suspensiton and pushing in the filament manually.. then it worked. So it should be an issue with the feeder I suppose. I will look in it again and send you in some fotos. Can it be that the feeder "didn´t get the info" sometimes from the hardware to advance and retract?

 

Does this always happen or just when you have newly loaded a filament?

[Harry Plotter 3]

Hey Dim3nsioneer and DF-Werkzeugservice,

 

I just started another print and (cross my fingers) thus and up until now, it worked fine (withot a starting problem printing PVA correctly in the middle of the printout (it got partly ripped away). But after a few layers it had stabilized again... so far so good. I can only tell you, after the print is finished. I will take another Day and a half for it to finish and if it finisheds I have a smoth solution to place my pad in my car!

 

So far to say I can say 2 things:

 

1. The feeder-roll was taped with PVA-powder, so I thouroughly cleaned it today (solving 1 problem I hope).

 

2. The bigger problem probably was that I used an experimental adjustment, that probably will not go good with PVA. I was the "adaptive layer" one. I was trying to save me 1 day...

 

Now it´s printing it regularly layerwise and everything seems to work out just fine.

 

Tell you tomorrow, if I´still happy...

 

See you

 

 

Daniel

[Brulti 177]

Adaptive layer works with PVA as well, I did a couple prints with it. I guess most of your problems were due to the feeder being dirty.

[Harry Plotter 3]

Hi Brulti,

 

that is what I thought, too... until the day bevore yesterday. I was all cleaned... but still the problem persists... Not i´ll try a higher print temp and a slower print velocity. maybe that helps...

 

Maybe the printhead is somewhat "worn off" it is always so dirty after a print. If you have any other clues you got the g-code, so you know what type of setting I use.. besides that I changed the "adaptive layer" away.

 

I will try it again this evening.

 

Greetings to all of you

 

Daniel

[Brulti 177]

That's strange... Maybe one thing to do would be to test with another BB core, if you have a second one available, see if the problem persists. Else, well, I wouldn't really know how to help you. I printed a couple pieces with PVA support and layer adjustment using the standard profiles for both PVA and whatever I was printing with, I think one piece was PLA and the other Nylon, I don't remember for sure.

 

I don't read gcode yet, so I'll let people who are more fluent in it read it and try to help you. ?

[Harry Plotter 3]

Hi Brulti,

 

I think you are right! I ordered a new core 2 days ago and I will get it on Monday. So I will let you know. I think the core was eaten up... I once cleaned the outside of the nozzle with sand paper and I scraped off too much so I kind of redid the nozzle-tip with a sandpaper of a smaller granulat and it kept working... but 1 month ago it was clogged too much so I decided to open the hotend and it was all burned up inside (I couldn´t even to a cold pull anymore). So I decided to drill it free with a dremel and a drill of the same size... it came free alright and it worked again, but I think now I changed somehow the incline of the inside of the nozzle itself. Yesterday I had to free it the same way and after reinstalling the tip in the hotend, I reallized that the filament flew free, but i got harder each minute to press it throuh so that the filament would flow out the same amount. I suppose that´s what happened now to the filament each time I try to print... at least that is my last guess, too. I hope the new core does last a little longer though.

I plan on buying one of the cores with changable tips (solex). Do you have any idea if that works better because spending 120 euros everytime that BB or AA core is clogged too much will destroy my pocketmoney for other things... ;O) and  the other nozzles come in different sizes, too.

 

I will let you know once the new BB-Core is installed if it workes better now...

 

Greetings

 

 

Daniel

[DF-Werkzeugservice 9]

Hi,

actually I haven't tried the 3dsolex BB Cores. But the AA matchless race are just awesome! Definitely worth the money plus the fact of cheaper nozzle replacement.

[Brulti 177]

Cleaning the brass nozzle of the UM cores with sandpaper is about certain to damage them. And you don't need to do it. Just warm them up, keep them warm for a moment, then wipe any bits of filament sticking on the nozzle with a cloth or something like that. And it will work like a charm. That's what I do with mine. The outside has this burnt color, but, as long as the tip of the nozzle itself is free and there are not bits sticking on it, it prints very well.

 

I bought a 0.6 Solex hardcore a couple months ago, to use with abrasive materials like glow and wood and such. Still tinkering with settings to find the right ones to print PLA with it. You need to print hotter, about 220°, and slower, but I haven't yet found the perfect setting for my UM3E. Though, based on what a few others said on the forum, those seems to be very good and durable, just make a search on the forums with the 'solex' tag, and you'll find all the threads.

[Harry Plotter 3]

Hi Brulti,

 

just like you said... it wasn´t the best idea.. nonetheless it worked on a couple of month. Now like I said I bought the original BB "again" and I will treat it like a princess hoping that it´ll last me a little longer. Only after this one will leave me as well I will try the Solex. Until that time I will try to optimise my knowledge with cura...

 

I will let you know it it ultimately was the hotend or not...

 

Greetings

 

 

Daniel

 

Btw: Do you know a filament that will not be destroyed in my dishwasher? Lat time I printed a coupling between a big BBQ-Bottle and a handpump. I worked great until I decided that it would be time to give it a wash. I used PC and in the sheet it sais it´ll be stable until 110 c°. My dishwasher uses 90 c°. When it came out clean, it was too much distorted, so I had to print a second one...

[Brulti 177]

Don"t forget that printcores are considered as consumables by Ultimaker. So they won't last you years. I had to buy a second one this year when the first one failed, though I think it may have been damaged when I had a print failed and create a big blob around the printhead. And I use them professionally, I run a small 3D printing company.

 

I recently printed an egg separator in PC for a friend, or, rather for his wife, but I think she washes it by hand, not in a dishwasher. I'll ask him and let you know. I do not know about filaments that can specifically resist the dishwasher, sorry.

[Harry Plotter 3]

Hi Brulti,

 

thank you again for your answer! Unless I get another filament that could withstand those temperature I also will forget about the ease of letting it get washed by my dishwasher (unless I hated the part anyhow)...

 

Now to the bad part: It failed again even with the new printcore. Now in this case I have one last thing to change --> the filament ! I will do that on Sunday. Then I will try it again and see what happens. If that failes again I am out of ideas...

 

I will report on Monday or Tuesday next week...

 

Greetings

 

 

Daniel

[Brulti 177]

That failed quite late in the printing... I hope for you that using a new spool of filament will work, that would mean the first spool you got went bad for some reason.

[Harry Plotter 3]

Hi Brulti,

 

simple answer: it was the filament! I don´t really know why, but it was the filament...

 

I didn´t use it too seldom and it also was "only" a half-spool. Did I mention that it was the filament?

 

Well I am happy now that it wasn´t some tricky bug in Cura or even worse, in the printer itself. So I hail to all persons who have supported me with their ideas on how I can go ahead.

 

Here is a final pic from the print. I´ll clean it tomorrow, because now it´s just too late to do that. I also took a timelapse of the print but the bastard of my PC killed 90% of all pics in the temp-file and thus the program ffmpeg wouldn´t find nothing anymore to compile. Such a s... (btw. that was my 1st 2.5 day-Print) ?

 

See you around

 

 

Daniel

 

PS: It was the filament! Strange, but true...

[kmanstudios 1,120]

35 minutes ago, Harry Plotter said:

PS: It was the filament! Strange, but true...

Not really...PVA can be a finicky beast

 

[Brulti 177]

That print looks nice and clean now, and I'm glad you found the problem. As Kman says, PVA is tricky. Though I guess that particular roll of filament was defective from the start, it happens.

[kmanstudios 1,120]

4 minutes ago, Brulti said:

Though I guess that particular roll of filament was defective from the start, it happens. 

It do, it do!!

 

I have opened PVA that crackles and pops when in first use. It does  not take much to damage a sealed pack.

[Harry Plotter 3]

Hi Brulti,

Hi kmanstudios,

 

yep probably that was it... I didn´t pay attention when I opened the box.. but nontheless the box was covered with the UPS box, so if I open it, that means goodbye for the money cause I lack the proove that it was defective the first place.

Well it was the first time for me and I hope that will not happen too often... as this would result in a russian roulette kind of buy. Anyhow now I posess 2 BB´s and I will try to reuse the first one. So if it works that save me the second until the first dies for good!

 

See you around!

[kmanstudios 1,120]

Just heat the PVA on a heated bed for a few hours on about 50°C. PVA can be restored :) All is not lost.

[Brulti 177]

Or leave it for a couple weeks on a box with some desiccant. I saved a roll this way.