Cura Filling in Top Corners of Models

[Adventurehill1 0]

On 4/15/2024 at 8:07 AM, gr5 said:

I've never had this "flaky surface layer" with petg - just thick stringing.  For me "stringing" is the only symptom I get when I have wet PETG.  Other than that the quality is okay.  When I dry the filament, the stringing goes away.

Here is another print I did. I plated two cubes, one with supports and one without, similar to how they are placed in the picture. The plastic is stringing, but only from the strange layer on the outside.

 

13 hours ago, Torgeir said:

Well, -It's the support that's destroy your model in the first place.

Rotate your model so the "Z" is pointing straight up, the turn off the support -then you will have a much better model to analyse, for the one trying to help you and for yourself.

 

Are you sure you're using a 0.4 mm size nozzle? Or, could it be a much to high feed rate setting in your firmware?

I'll ask this as the line width setting in this last model was 0.24 mm (for a 0.4 mm nozzle) Cura warn you here with "Min layer width 0.34 mm). Still your model looks like this.(?)

 

You're using Cura 5.6.0 , Anycubic advice using Cura 5.2.0 as the profiles are made with this version, I would jump to Cura 5.7.0!

 

Maybe you tell us a little bit more about your printer.

 

Thanks

I did a print without supports and it did the same thing. 

 

I also double checked the nozzle setting and, yes, it is a 0.4. As for feed rate settings, I assume you are asking about E steps? I have calibrated those.

 

I just got Cura 5.7.0 yesterday, I will switch.

 

Hopefully that's helpful.

[Torgeir 243]

Hi @Adventurehill1,

 

This answer quite a few thing.

The versions of Cura before ver. 5.60 had some weird issue just with the support on certain places, but not on all print objects. This might also occurs differently caused by "some" model / profiles..

When come to the version 5.60, I've had some issues with it, -but with the new arachne version all (I've seen) this is gone.

 

I'll think this version; Cura 5.70 are the best version I've seen from Cura.

 

I wanted to see you printing the cube with "Z" up -just alone without any support, just to avoid the stringing from the support. This way, you may isolate problems one by one -I'd like to think..

 

I'll think you're right in assuming there is no under extrution.

The E-step are calibrated numbers / mm you confirmed.

 

Did you ever print with PLA with success or.(?)

This will be kind of indication that your firmware are working OK.

 

Thanks

[Slashee_the_Cow 271]

Given the stringing between those, I think what @Torgeir means is to print them individually. Turn support off, print one, turn support on, print one.

[gr5 2,176]

Okay printing something different is actually helpful in diagnosing the issue.  I see a LOT of heavy stringing. I don't trust your filament dryer.  How hot did it get?  Did you unspool enough filament for a cube?  How long was the filament in the dryer?

 

For PETG, 8 hours at 50C should be enough to dry any unspooled filament.  Within a week the filament may be "wet" again - I'm not sure as I keep mine pretty dry.  PETG seems to take longer to get "wet" than nylon or pva.  To dry the entire spool it could take many days as the humidity may be far towards the center of the spool.

 

I do like Torgeir's idea of maybe printing some PLA to verify your equipment (such as feeder steps/mm as mentioned).

 

Also are your issues only when there is support material involved?  Is everything printing beautifully when there is no support?  For parts that have potential to string (islands of printing on each layer)?

[Adventurehill1 0]

On 4/16/2024 at 9:50 PM, Slashee_the_Cow said:

Try printing this. I tweaked a few of the settings for (hopefully) better results.

StrangeCalibrationCubeTweaked.3mf 113.49 kB · 2 downloads

I tried those setting sitting flat (Z straight up) and it worked beautifully. I do need a smaller layer height if I can possibly get it though.

[Torgeir 243]

Hi @Adventurehill1,

 

Good news, but did you use Cura 5.70, -or the previous 5.60?

Your printer Positioning Accuracy X / Y / Z 0.0125 / 0.0125 / 0.0025 mm (from the user manual).

Every Z micro step are 2.5 micron, so you should be able to print "some" tiny layers..

[Slashee_the_Cow 271]

15 hours ago, Adventurehill1 said:

I tried those setting sitting flat (Z straight up) and it worked beautifully. I do need a smaller layer height if I can possibly get it though.

You can try (I'd start trying at 0.1mm because I like nice round numbers) but I can't make any promises, it's sort of up to the printer at that point.

[Adventurehill1 0]

On 4/18/2024 at 12:31 PM, gr5 said:

 I don't trust your filament dryer.  How hot did it get?  Did you unspool enough filament for a cube?  How long was the filament in the dryer?

My dryer gets to about 110F, which does seem cold to me. I didn't unspool any filament and I left it in for 8 hours.

[Adventurehill1 0]

9 hours ago, Slashee_the_Cow said:

You can try (I'd start trying at 0.1mm because I like nice round numbers) but I can't make any promises, it's sort of up to the printer at that point.

Ok I just realized I used the stock TPU setting accidentally instead of your tweaks. I'm shocked that it even melted enough to do anything at 210 degrees. I'll print one with your settings.

[Adventurehill1 0]

5 hours ago, Adventurehill1 said:

Ok I just realized I used the stock TPU setting accidentally instead of your tweaks. I'm shocked that it even melted enough to do anything at 210 degrees. I'll print one with your settings.

I ran a quick print with those settings and support turned on. It definitely improved the stringing problem, but didn't solve it completely. I'm curious what setting you tweaked?

[Slashee_the_Cow 271]

11 hours ago, Adventurehill1 said:

My dryer gets to about 110F, which does seem cold to me. I didn't unspool any filament and I left it in for 8 hours.

Mine has settings for 40, 45 or 50° (C). Too much hotter and some kinds of filament can start to melt. Mine actually has pluggable holes in it for filament to come out (it holds two spools) so you can keep it in the dryer while it prints (since I have my printer in a tent I just use some spare Bowden tubing to get it through one of the cable holes). The minimum time setting is six hours, which I should probably take as a sign, but I start printing when it's been in there 2-3 hours and haven't had any problems (even in an Australian summer where the ambient humidity can reach 100% - it's a good thing I have no idea what that's a percentage of, but I guess it doesn't mean "the air is water").

 

5 hours ago, Adventurehill1 said:

I ran a quick print with those settings and support turned on. It definitely improved the stringing problem, but didn't solve it completely. I'm curious what setting you tweaked?

*/me looks at both files side by side*

 

(yours left, mine right)

Printing Temperature: 225 > 240

Printing Temperature Initial Layer: 230 > 245

Initial Printing Temperature: 225 > 240

Final Printing Temperature: 225 > 240

Infill Flow: 105 > 100

Support Flow: 110 > 100

Initial Layer Flow: 110 > 105

Retract at Layer Change: On > Off

 

That's about all I can see from having the settings open side by side 🙂 Didn't there used to be a plugin where you could export profiles as HTML or something?

 

I'm not sure what you're expecting when it comes to stringing, but you'll never "solve" stringing with PETG. It's just stringy by nature (more so if it's damp). Ideally you get it down to the point where all you need is pliers (easy to grab a bunch of strings and pull them out), some wire snippers (to get bits on the surface), a craft/hobby knife (for awkward places you can't get the wire snippers into) and possibly some cut-resistant gloves (if you're as clumsy as me, although I managed to cut myself through them anyway).

[Adventurehill1 0]

I decided to run a print with almost stock TPU settings, just as an interesting test. It actually worked like a dream! Thank you guys for your help, it was extremely useful.

Good PETG CalibrationCube.3mf