I have been having some substantial issues printing taller / thinner parts. What ends up happening is that the Print starts out alright - Everything looks good - but eventually the Filament begins to curl upwards. The Nozzle starts hitting the print and eventually breaks the piece. I have attached two examples of the most recent - failed - prints.
This almost exclusively happens on areas with a very small surface area - Usually Legs, Tails, Staffs. At first I believed this to be a Z-Hop Issue but No - It’s just that the Filament curls, layers become uneven, Nozzle hits and ultimately breaks the print.
I have tried:
Different Filament (I’m using Sunlu PLA Meta, printed at 190 Degrees and Sunlu PLA+ at 200-205 Degrees. I’m printing at a very low speed and these are the recommended temps for the print speed range.)
Printing at both a higher and lower temperature.
Increased the Fan Speed from 60 to 70, then to 75. Didn’t work. Decreased it down to 50, doesn’t work.
Lowered the Temp of the Printplate from 65 to 60 Degrees, didn’t work.
Supports don’t make a difference - They either suffer from the same issue or just end up getting knocked over by the Nozzle once the deformation starts.
Print Plate is clean and fully calibrated. This is not an Adhesion Issue - The Print doesn’t get knocked over, it literally breaks after being hit by the nozzle several times.
Kept the Windows closed during the print to avoid any changes in temperature because of the Wind, nothing changed.
Filament is fully dried.
These are not failed bridges or overhangs either. It happens to straight parts, like a Staff, as well as to parts that eventually spread out.
I have no idea what to even try anymore. Raise the temps even more? Lower them? Increase / Decrease Cooling even more? Again, this only happens on areas with a small surface area - Flat / Large Prints don’t have any warping issue whatsoever. Anyone got an idea?
From what I remember, this issue is related to uneven (or lacking) cooling while printing overhangs.
Things you could try:
Decrease overhang print speed (there is an extra option for that in the slicer), or the overall flow to something really low like 5mmÂł (based on the post, I guess you already did that)
Enclose your printer in for example a cardboard box or a plastic one. Preheat the bed for a bit (30min to 60min at 100°C) to make the “chamber” warm up before printing. That should result in the print not cooling too rapidly.
Unfortunately I’m already printing at very slow speeds (Usually around the 50mm/s mark, with overhangs specifically slowed down). I’m not sure how much lower I can go without introducing other issues.
Enclose your printer in for example a cardboard box or a plastic one. Preheat the bed for a bit (30min to 60min at 100°C) to make the “chamber” warm up before printing. That should result in the print not cooling too rapidly.
I did consider getting building an enclosure…Though I’ve heard somewhere that it was actually recommended not to put the A1 into one, because of potential heating issues? But I’m not sure if that’s true.
Right now I’m having another testrun. However, I’m getting some conflicting information - Most people I asked seem to agree that this is a cooling issue, and I believe so too. Otherwise it wouldn’t happen ONLY on small surface areas.
However, whether it’s too much nor not enough cooling…That’s a different story. Some folk recommend me to print with the cooling fans cranked up to 100%, which I’m currently trying out. If you are correct however, it should make the results even worse because it cools even faster, no?
in my case, no. The lower layers are perfectly fine - If the lower / bottom layer of your print begins to warp and curl, 9/10 times that’s an adhesion issue. You could try cleaning your printplate with dishsoap-water and run the bed leveling again.
and cuz the layer below is still warm so the top layer is like melted the lower layer and cuz when a thing is hot like thermoplastic it expands and when is cools down it shrinks so first the top layer melt the lower layer the two layers are welded togeather the top layer shrinks when it cools down it lifts the lower layer please tell if my explination is correct pls
You mentioned you closed your windows, but, do you have any other sources of “wind” in the room the printer is in? For example, when I print with my A1, I turn off my room fans to avoid external cooling factors from affecting the print. Namely, AC and fans can be something to look out for.
It’s not recommended to use an enclosure with the A1 because the central electronics in the printer aren’t cooled and are susceptible to overheating when introduced to an environment where the temperature is already high. Enclosed printers like the P1S combat this by having dedicated cooling fans for the electronics themselves, which prevents overheating. As a test, you could use a makeshift enclosure to see if that fixes your issue, but it’s not something I’d recommend in the long run. If it prints fine in an enclosure, that suggests the issue lies from external factors as I discussed above.
One other thing I have found to cause similar issues is actually the Z-Seam, although this would only cause curling on the seam and even then, most of the time, the curling would only occur on seams located on overhangs. This is something to consider, although based on your first image showing two areas curling on the same part, I doubt this would be the cause because there should only be one seam and therefore one area curling.
Otherwise, this is a cooling issue, either too much or too little as I believe you’ve already narrowed it down to.
Yep. That is it exactly. Both warping and curling are caused by this.
So to combat this root cause, only few options exist:
Enable more uniform cool down by printing WARM and eliminating unwanted drafts. With PLA, only ironing or really hot summer days are a problem regarding nozzle clogs.
Limit the volume of material (re-)heated: Print at low layer heights. Adaptive layer height is great to tailor that. Halving the layer height reduces the amount of heat input per layer by a factor of 8 as it is a cubic relationship while maintaining actual print temp.
If all else fails, also reduce the printing speeds in the troublesome areas. This also reduces the heat per unit time in a cubic manner. But do not go so slow that the nozzle heats up the prior layer As warping effects get worse the higher the lever arm to the central print plane is, it can be beneficial to slow speeds higher up.
Keep in mind, that warping and curling can be drastically reduced in this manner… but not neccessarily completely eliminated. Depending on the model, drastic layer height and local speed reductions may be needed.
I increased my Fan Speed and the Temperature of the Filament, but what I believe to be the culprit was something else: Z-Hop. I used to print with a very small, essentially non existent Z-Hop and have now increased it to a whooping 0.95 switching to Spiral Mode.
What I believe happened was: Without the Z-Hop the Nozzle lingered around the affected areas just long enough for the radiating heat to prevent the filament from cooling evenly, potentially even reheating / resoftening it. That would explain why it exclusively happened around the very small, thin areas of the Miniature, like the Tail or Staff of the Anubis Miniature. On larger areas this wasn’t an issue, because the surface area it impacted was only a small section of the print - whereas well, with these smaller areas, the affected surface area is essentially the entire surface area. It messed with the cooling, warps started to happen, followed by desaster.
Unfortunately the increased print temperature also re-introduced some slight stringing. Nothing I couldn’t deal with post-print, but regardless, I will attempt another print tonight with the same Z-Hop and Fan Settings, using the original Filament Temps to see if I can prevent the stringing. Wish me luck.
Other than that, I’m fairly happy with how it turned out, considering it’s a FDM Print. I have spend the last two-three months obessing over optimizing my print settings and squeezing every bit of detail out of my machine, and I think I’m finally close to my “perfect” settings.
And thanks for getting back to us. That nozzle lingering effect is more often seen on peak like tops rather than mid print but makes perfect sense. I’d never have attributed to mini-z-hops myself though so many thanks for sharing this excellent troubleshooting.
Thx very much for posting your story and congratulation on the results.
However, the pictures are quite blurry, so I can’t fully assess the quality. Could you please post the pictures in high resolution and in focus? Thank you very much in advance.
Of course. Usually I record all of my prints in a Lightbox with a short video, but the forums don’t allow video formats, so I had to take sceenshots of the recording.
Anubis Miniature:The one with the base was the successful print from last night, I still have some minor cleaning to do with both of them, as well as prime them.
Sorry for the Doube Post, forgot to mention it - Glad I could provide some information for a fix, in case somebody else stumbles across the same issue
It certainly took me a while to figure out that it’s related to the Z-Hop. I was very hesistant to change my settings, because I firmly believed “The Nozzle isn’t hitting the Print because of the Z-Hop, it’s hitting the Print because of the warping. It wouldn’t fix the issue, it would just hide it better.”
But then I remembered the peak-like tops you have mentioned (In my case, it was a Wizard’s Hat) and that they looked like they melted a bit, and had a signifcant drop in print quality…And then I realized what the culprit might be and just gave it a try. I’m happy that I finally have a solution.
Thank you very much for the pictures. Still a bit blurry, but the print quality is almost perfect.
And that last photo! I’m happy it works fine for you.
Now I’m wondering if I should give the X1C a second chance. I returned the first X1C because the print was not going well. This included printing jewelry (rings) with a 0.4mm nozzle. I will discuss your story with my colleague and show her your results. We still need to solve the very low quality of the top layers, e.g. when printing medals, as well as resonances, blobs and other various unwanted artifacts. I’ll probably open a new thread and ask there.
Thank you again for the enormous amount of effort you put into this problem and for sharing your experience.
Over the course of my research, both looking up guides as well as learning by doing / trial n error, I found that FDM Prints (For Miniatures, at least) struggles with cylindrical and spherical shapes the most, which could explain why you are dissatisfied with the results of rings and medals.
You are more than welcome to tag me should you open up a Thread, and I will try to help you out with what I learned. I’m using the A1 instead of the X1C, but I’m fairly certain that when it comes to the general settings this shouldn’t make too much of a difference. I also plan to write down an extensive guide where I go over each of my Slicer Settings and my general approach to the FDM Print. Once I’m done, I can tag you if you wish?
As warping effects get worse the higher the lever arm to the central print plane is, it can be beneficial to slow speeds higher up.
