Almost always missing layers / underextruding

[Nicolinux 288]

Hey guys,

I've got another little theory about underextrusion. Maybe the way filament is stored makes a big difference in its stiffness/springiness. I remember that illuminarti stated he was able to straighten filament by hand. With my filament (only from Ultimaker) I can't do that very well. It is very stiff and it won't straighten. Only if I bend it too much against its natural curvature. But then it tends to form a sharp corner.

I store my filament in a big airtight box that's full of dessicant packs. At home I have in-floor heating and the box did warm up a little. Maybe it did influence the filament. I have now moved the box somewhere else where the heat won't reach it.

But it would be interesting to find out if others have similar storage environments.

 

[SandervG 1,521]

Hi Nico,

I have read your post and copied pasted fragments to those who should be addressed.

I will follow them up in a few days if I haven't heard back.

Thank you very much for your feedback, it is much appreciated.

@ Braddock, I understand your point about an expensive machine that is/should be reliable and how frustrating it can be when this is not the case. I also agree with Nico about the first revision part. However if that may be the case or not, in no way should this disadvantage the users.

We support all users like many on the forums now that go through all the efforts to troubleshoot the under extrusion and come with solutions. Really, that is what makes Ultimaker great!

However we are not relying on this, so Braddock if you feel you are not getting the max. out of your Ultimaker 2 please contact either me or the sales team and we will do our best to isolate your problem and get you back to your fully positive 3D Print experience. Ok?

About the filament, I have always had this in the back of my mind.

Different colors require different temperatures, different suppliers have different stiffness.

There are so many different gradients in just 'PLA', that it is hard to tell what you get from which supplier.

Especially I think what we are suffering from now is the stiffness of the filament.

Has anybody ever checked the filament during/after under extrusion if it was still round or oval?

- How does this compare with a piece of filament that has not went through the feeder yet?

I think if you store the filament near a heat source the moist can evaporate, and it will make it more stiff or perhaps brittle? Does that make sense?

 

[das_enginer 2]

About the filament, I have always had this in the back of my mind.

Different colors require different temperatures, different suppliers have different stiffness.

There are so many different gradients in just 'PLA', that it is hard to tell what you get from which supplier.

Especially I think what we are suffering from now is the stiffness of the filament.

Has anybody ever checked the filament during/after under extrusion if it was still round or oval?

- How does this compare with a piece of filament that has not went through the feeder yet?

I think if you store the filament near a heat source the moist can evaporate, and it will make it more stiff or perhaps brittle? Does that make sense?

 

Hi Sander,

This is something I've been looking at closely with the filaments I've had, albeit only 3 suppliers. My Faberdashery filament is the most pliable of all of my filament, but still fairly stiff. The Ultimaker filament that came with my printer is stiffer than the Faberdashery, but the black I got from MakerGeeks is the stiffest of all of them (though not MUCH stiffer than the Ultimaker). This matches the ease of printing with them; the Faberdashery is the easiest, then the Ultimaker, then the Maker Geeks, but this is probably skewed by the Faberdashery having a much larger bend radius than the others.

I did a quick measurement on my filament, and a strand extruded in air is pretty round (0.39mm to 0.41mm), where the input Ultimaker filament is also round, but less so (2.85mm to 2.92mm). I didn't check my Faberdashery yet, and have stopped using the Maker Geeks for the time being.

In terms of removing moisture, I've heard this is beneficial for print quality as it will produce less defects since any water in the filament will steam when it's extruded (and make a small popping noise). I don't know how heat will affect this, since it can change the structure of the plastic of its own accord. Personally I store my filament in a bag with a large desiccant pouch I bought from Amazon, and this keeps most of the moisture out, but I've not noticed a change in stiffness.

 

[braddock 1]

Hi guys, I'm tempted to say my under extrusion issues are solved, but first this...

So, last night, I set up my badly under extruded spool roller setup, and set off another print for the stand part, same gcode, no changes, other than using the new spool roller, sitting on the floor.

I woke up this morning to this... a badly wound spool from UM (came with the printer) I have previously cut great sections off this particular spool because I could see it was poorly wound... anyway, I'm about out of filament, so my options were limited.

The whole spool roller was actually hanging by the filament due to the tangle this morning.

See the tangle here

Regardless of this, the print did actually finish, with only a few areas affected by the tangle.

If not for the poorly wound spool, this would have printed flawlessly. Printed at 0.25 layer height, and 50mm/s it's also the largest thing I've printed.

So, for me, my under extrusion has been a combination of the bowden head needing to be seated properly without any play, and the filament feeding into the extruder with no tension, and rolling easily off the spool.

 

 

 

[Nicolinux 288]

@braddock: Nice. Hopefully that's the solution then.

What irks me though was the fact that illuminarti and gr5 were able to print from the stock spool holder with ultimaker filament and still achieve 10mm^3/s. I doubt that a half empty / nearly full spool would make such a difference. But then again, maybe the whole underextrusion mess is just a complex problem made up of many variables.

@Sander: Good to hear that you guys take feedback seriously.

About the filament. I don't think the roundness makes a difference because underextrusion can be triggered reliably when increasing the filament volume (in illuminarti's test object). It would be too much of a coincidence if with the increased volume the filament happened to become oval before it enters the feeder. But maybe I didn't understand correctly. Did you mean the extruded filament strands (like Das_ENGINER tested) or the normal filament before it enters the feeder?

 

[braddock 1]

Nico, I was also able to do this, but it was unpredictble depending on which filament, how it was wound on the spool, how much was on the spool etc. I'm hoping the ball bearing roller, positioned directly beneath will iron out a lot of these variables.

Have you ever tried a similar setup? I know you tried teh lazy suzan, but I don't think that would be as affective.

One thing I noticed instantly, was that there's no tension on the filament feeding into the extruder. It was almost always tight using the original spool holder.

 

[Nicolinux 288]

I tried all kinds of spool holders. But since my filament seems to be very stiff, it would still curl up when it reached the feeder (when using the lazy susan). I then triend a spool holder with four ball bearings where you'd just put the filament spool on the ball bearings. Worked better than the lazy susan. I am now using Robert's spool holder (featuring two ball bearings). There is virtually no resistance with this one - only the resistance from the filament curvature itself remains (which is always there, regardless of which solution is used).

 

[braddock 1]

And Roberts holder still didn't help you out with your first UM2? What brand of filament do you use that's so stiff?

 

 

I tried all kinds of spool holders. But since my filament seems to be very stiff, it would still curl up when it reached the feeder (when using the lazy susan). I then triend a spool holder with four ball bearings where you'd just put the filament spool on the ball bearings. Worked better than the lazy susan. I am now using Robert's spool holder (featuring two ball bearings). There is virtually no resistance with this one - only the resistance from the filament curvature itself remains (which is always there, regardless of which solution is used).

 

[Nicolinux 288]

No it didn't. I am using only Ultimaker filament.

 

[braddock 1]

Same here, exluding my spool of Colorfabb that had issues. I have a new spool to try now.

 

 

No it didn't. I am using only Ultimaker filament.

 

[chrisp 10]

Hey Nicolinux and Braddock,

I feel your pain!

I have been waiting for almost 3 weeks to have DHL come by and pick up my printer to exchange it for another. They finally contacted me today. I am out of options to try and fix my under extrusion problems.

On the positive side, The Ultimaker Team has been one of the best companies to deal with ever! Their customer support is second to none.

I can't wait until these issues are finally solved and fine tuned.

Sometimes it takes a few patient people to find the answer.

 

[pikey 0]

Filament plays a huge role in the print speed test. I've been able to get a perfect print from 3mm³/s to 10mm³/s multiple times with Ultimaker Blue and Prototype Supply Black (from http://toybuilderlabs.com/pla-300/black-pla-filament-300mm-1kgroll). Now I'm using http://toybuilderlabs.com/pla-300/orange-pla-filament-300mm-1kgroll and I can hardly get past 3mm³/s before my Ultimaker² starts under extruding like crazy.

Right now I'm using Geeks feeder design, and it was working flawlessly with the black filament. So far I've dropped my print temp from 230c to 220c for the orange and that seems to be working a bit better. I'm doing some small calibration prints before I do my next print speed test.

PS. Black is not a fun filament color, my desk looks drab with all these black items.

 

[geeks 1]

Indeed! I also noticed having to lower the temperature a bit with my V2 extruder.

 

This is because I have limited input force to concentrate on the strength of the extruder output. This results in a little more material in the nozzle.

 

But I'm not surprised by what Pikey said

 

[pikey 0]

10mm³/s is a moving target...

 

[pikey 0]

I think I'm posting too much...

Here is a Geeks/Robert FrankenFeeder. I used the spring assembly from Geeks feeder design on Roberts feeder. It compliments the rest of my Geeks/Robert design Ultimaker² very well.

How does it feed? I don't know. I can't tell you because this orange filament does whatever the hell it wants whenever it wants. I've been printing it at 210c and get good results, but still can't make it past 8mm³/s consistently.

Maybe changing filament at the same time as the feeder (twice) was a bad idea... live and learn.

 

[illuminarti 18]

That orange filament looks like it has some bends and noticeable corners in it; I wouldn't be at all surprised if that was hard to feed - I'd imagine it can press itself against both sides of the Bowden tube at once like that.

 

[pikey 0]

It seems to print better the farther into the spool I get, maybe its because I'm being careful. I'm printing .06 layer height at 70mm/s right now, nice and safe.

Here is a picture of when I had Geeks feeder mounted. I really liked it, but I'm finally getting my fasteners in to try all the available designs. In the photos below I hadn't yet guided the filament through the guide pulleys before I took the photo, whoops.

 

[geeks 1]

It feels weird to see my extruder devised and tested in France, in the countryside, and printed thousands of miles away. :oops:

 

And it makes me really happy too.

 

I was able to demonstrate that they could now trust in my drawing. The results were there. I am still waiting for tests users I solicited. I do this before released on Youmagine completely in order to be sure of the quality of output.

 

I admit that it is not simple and adhere to all requirements and that correspond to all.

 

@ Pikey. Did you try out slightly moin fluid yarn. A temperature of 5 to 10 ° C in less than? I noticed that when I was lowering the temperature a bit, but not too much support for the following extrusion was increased. This allows you to build solidly to the floor above.

 

Example PLA orange Ultimaker:

Failed at 230 ° C to 7mm3 / s

Failed in 210 ° C to half of 10mm3 / s

 

[gr5 2,172]

@PIKEY - those bends in your orange filament are severe. If things are "getting better" it might be because of fewer bends the further into the spool you get.

 

[chrisp 10]

Hey Nicolinux and Braddock,

I feel your pain!

I have been waiting for almost 3 weeks to have DHL come by and pick up my printer to exchange it for another. They finally contacted me today. I am out of options to try and fix my under extrusion problems.

On the positive side, The Ultimaker Team has been one of the best companies to deal with ever! Their customer support is second to none.

I can't wait until these issues are finally solved and fine tuned.

Sometimes it takes a few patient people to find the answer.

I just wanted to make sure that my post didn't come through the wrong way or give the wrong impression.

I just realized that not everyone has heard of, or understands the impression, "Second to none".

In my book, it means number 1, like no other, the best.

Just thought I would clear that up so nobody takes it in a negative fashion. :cool:

 

[pikey 0]

It feels weird to see my extruder devised and tested in France, in the countryside, and printed thousands of miles away. :oops:

 

And it makes me really happy too.

 

I was able to demonstrate that they could now trust in my drawing. The results were there. I am still waiting for tests users I solicited. I do this before released on Youmagine completely in order to be sure of the quality of output.

 

I admit that it is not simple and adhere to all requirements and that correspond to all.

 

@ Pikey. Did you try out slightly moin fluid yarn. A temperature of 5 to 10 ° C in less than? I noticed that when I was lowering the temperature a bit, but not too much support for the following extrusion was increased. This allows you to build solidly to the floor above.

 

Example PLA orange Ultimaker:

Failed at 230 ° C to 7mm3 / s

Failed in 210 ° C to half of 10mm3 / s

I've been playing with that all day, I ended up going back from the Robert/Geeks feeder to the Geeks feeder. So far this has been a very reliable feeder! Roberts feeder was well designed, but I think my spring was too tight for it because it cracked. No pictures for now =[

@PIKEY - those bends in your orange filament are severe. If things are "getting better" it might be because of fewer bends the further into the spool you get.

I hope so, I contacted the manufacturer and they said that those bends might be from the vacuum sealing. Now that I'm back to a reliable feeder I'll break out the orange and give it another try. I'm printing in "silver" from the same manufacturer now (Prototype Supply/Toybuilder Labs) and am getting better results than I was with orange. I still had the best results from Prototype Supply Black and Ultimaker Blue.

 

[IRobertI 520]

Roberts feeder was well designed, but I think my spring was too tight for it because it cracked.

Where did it crack?

 

[woofy 12]

ALMOST HAPPY!

My new Telflon and Nozzle parts arrived today. Just in time, my UM2 is almost dead, so I decided to replace both parts at the same time.

Here the "before replacement" test as a reference point.

After replacement this is what I got

Way to go!

That's NOT under extrusion you're looking at. It's horrible melted PLA because I broke my fan cable. There was no skipping of the feeder at all.

That's fixed and I'm printing again right now.

Just peeked at it, its up to 5mm3/Sec ok.

I'll be back in 10 minutes or so.

This is tense.

 

[Nicolinux 288]

Where did you put your filament spool? Floor, lazy susan, stock spool holder?

 

[woofy 12]

HAPPY!

Perfect 10/10

Whooooppeeeeeeeee!