Creality Filament (PLA) for Prusa (mini) printers?  

RE:

Posted by: @quattro

....

my question is: am I not supposed to use a Creality filament in my MINI+? is there any technical reason or does someone not want tist to work although it is technically possible?

That's a silly way of thinking. Printer doesn't know what type/brand of filament you're using. All needed parameters are in slicer and you just need to find the right values -these values don't only depend on your particular filament, but also on object you print.

tried so far: extrusion multiplieter 95%, 92&, slight temperature changes.

Why would you decrease extrusion, if you only have trouble on first bottom layers? Think... why only bottom layers expand? Maybe because it's too hot below... or maybe you should change "Elephant foot compensation"... or maybe Creality filament is more "difficult to print".
And finally, why are some of us ready to pay slightly more for filament? Because, if 20% of objects printed with cheap filament land in bin, we end up cheaper actually.

RE: Creality Filament (PLA) for Prusa (mini) printers?

Posted by: @bogdanh

 

Posted by: @quattro

....

my question is: am I not supposed to use a Creality filament in my MINI+? is there any technical reason or does someone not want tist to work although it is technically possible?

That's a silly way of thinking. Printer doesn't know what type/brand of filament you're using. All needed parameters are in slicer and you just need to find the right values -these values don't only depend on your particular filament, but also on object you print.

there is this phrase "there are no silly questions". perhaps you want to elaborate on what part of those two questions are you referring to and why. let me clarify in advance: I went from "there is not Creality filament profile in Prusa Slicer because no one made one for an unknown but also not so relevant reason. I assume laziness combined with lack of need" to "oh, there is a Crality filament profile in Prusa Slicer but it was hidden from me for some reason.". hence my initial assumption for a reason why I do not see a Crality filament profile was invalidated. 

suddenly the reason gets important. here are some assumptions:

1. no one at Prusa tested this filament with the mini or i3 thoroughly enough to provide the perfection we are so used to see in everything bearing the Prusa name. -> lack of data
2. they did test it and decided that this is a hopeless cause and no one will ever be able to print this in any of the current Prusa printers lineup with perfect or at least decent quality. -> technically impossible
3. Creality is a competitor and therefore we don't want our customers using their filament. (most unlikely) -> dark intentions

reasons 1+3, I can work around and arrive at a solution. reason 2 however means that since Prusa (with their vast resources and experience) could not do it, I can not do it. hence I shall stop wasting my time trying. I don't think this could be classified as stupid.

tried so far: extrusion multiplieter 95%, 92&, slight temperature changes.

Why would you decrease extrusion, if you only have trouble on first bottom layers? Think... why only bottom layers expand? Maybe because it's too hot below... or maybe you should change "Elephant foot compensation"... or maybe Creality filament is more "difficult to print".
And finally, why are some of us ready to pay slightly more for filament? Because, if 20% of objects printed with cheap filament land in bin, we end up cheaper actually.

glad that you asked: the expansion coincided with the bottom layers and I measured the filament at 1.82mm (just one point of measurement) and the area of a circle with a diameter of 1.75mm is 92% of the area of a circle with a diameter of 1.82mm. so changing the extrusion rate was a path worth exploring imho.

temperature is another thing I'm currently investigating. my motivation for this post was not "help me to get this filament to behave", I will figure that out eventually and hints are always welcome. the bigger part of the first post was to illustrate what led me to the question in the last paragraph.

I agree with your formulation of "you get what you pay for". however.. we are talking about 15€ CrealityPLA  vs. 30€ Prusament PLA.

So, I use the cheap stuff for prototypes and Prusament for the final print. my design skills are not really good yet, so I do a lot of prototyping and a lot of the prints go into the bin but not because of the print quality. suffering from a few drawbacks can be justified in this case. 

however: if there is a way that I could avoid cutting all the excessive material away so the parts fit together right from the print bed then I'd like to know 😉

RE:

The only caveat to Bogdan's points is filament width and the ptfe bowden tube.  The mini is a bowden printer and the ptfe tube that carries the filament to the hot end is specified with a certain internal diameter.  Filament with poor quality control can vary the width quite a bit.  If it gets too wide then that can introduce friction into the feed path (even though ptfe is 'slick').  This doesn't help with smooth feeding.

Instead of altering your extrusion multiplier you really need to make sure the filament diameter configured actually matches the measured average of the real filament using a set of calipers.  Most people forget about that step.  If you have 1.75 in there and the actual filament is 1.76 then its going to over extrude.  If the diameter is thinner then it will under extrude.  

Edit - looks like you replied to Bogdan while composing the message. 

RE: Creality Filament (PLA) for Prusa (mini) printers?

Just to clarify.. by saying "silly", it's meant "unreasonable" (and not stupid).
Ok, for whatever reason, Prusa didn't include profile for your filament. You have three choices: find settings by yourself, you get settings from someone who successfully uses that filament on the same printer, or you decide for another brand.
I never tried Creality filament and I don't say it's a "bad" filament. But if I wouldn't get decent result at "normal" settings, then I would move to another brand -simply as that.
Yes, Prusament PLA is very expensive (it's good, but overpriced in my opinion). But there are other cheaper known brands, maybe few euro more expensive than Creality. I tried AzureFilm PLA, which is less known in this forum, and I got quite good results -and so I decided to stick with it for now.

RE: Creality Filament (PLA) for Prusa (mini) printers?

thank you for your insights!

I put them to good use. I created a Creality user profile. things I have altered:

• color (to give me a hint of what I'm about to do)
• price
• Nozzle: 205/200 first/other
• Bed: 55/50 first/other

lowering the temps reduces the high expansion and rising the z level my 150µm completely fixed the elephant foot for the prusament (I did not touch the temps there) and reduced it greatly with the creality.

I ordered some spools from AzureFilm. their silk PLA is strange, they recommend rather high temperatures.

RE:

I've never heard the term Linear Advance before so, I did noch mess with that.

I just read this https://help.prusa3d.com/en/article/linear-advance_2252 and I now understand what it is.

judging from the prints, the k-value used is not completely wrong. the prints look just like the part labeled "good". I will do this test anyway and see what happens.

I think, I understood how this template language works:

M900 K{
    if printer_notes=~/.*PRINTER_MODEL_MINI.*/ and nozzle_diameter[0]==0.6
        }0.12{
    elsif printer_notes=~/.*PRINTER_MODEL_MINI.*/ and nozzle_diameter[0]==0.8
        }0.06{
    elsif printer_notes=~/.*PRINTER_MODEL_MINI.*/
        }0.2{ #  <- MINI with 0.4mm nozzle
    elsif nozzle_diameter[0]==0.8
        }0.01{
    elsif nozzle_diameter[0]==0.6
        }0.04{
    else
        }0.05{
    endif
} ; Filament gcode LA 1.5
{
    if printer_notes=~/.*PRINTER_MODEL_MINI.*/
        };{
    elsif printer_notes=~/.*PRINTER_HAS_BOWDEN.*/
        }M900 K200{
    elsif nozzle_diameter[0]==0.6
        }M900 K18{
    elsif nozzle_diameter[0]==0.8
        };{
    else
        }M900 K30{
    endif
} ; Filament gcode LA 1.0

oh... the gcode for calibration has a model check built in and it's not written for the mini.

and the k values for thew mini are quite different than the ones for the i3. I guess I won't do this any time soon but I also don't feel the need to do so at this point in time with the creality filament. would be nice however to do this in the future just for curiosity^Wscience.

thanks @neophyl for the explanation. this actually explains a lot. the answer to my initial question is obviously: lack of data

RE: Creality Filament (PLA) for Prusa (mini) printers?

Posted by: @quattro

.....

oh... the gcode for calibration has a model check built in and it's not written for the mini.

and the k values for thew mini are quite different than the ones for the i3....

I'm talking about Mini here, which has default K=2.0 value.

I have made a test print object (XY size about 50x50mm), where I changed K value from 1.0 to 3.0 (in 0.5 increment) every 4mm in height. And honestly, there was no visible change in print result. That is, I expected to see changes in corners, where print head rapidly changes direction. I also increased print speed slightly to provoke K impact more, but again, no visible changes. I have also examined resulting G-code, to make sure that desired K value from custom G-code, is actually implemented -and it was.

This makes me thinking... Maybe Mini doesn't read/use K values from G-code at all? That would also explain why I couldn't find any LA test print (custom made for Mini) on the web.
Ok, it's also possible I didn't make my test print properly. So, if anyone successfully experimented with LA on Mini, I would be happy to learn.

RE: Creality Filament (PLA) for Prusa (mini) printers?

All K values in my previous post should be divided by 10 (i.e. default K=0.2 value).

RE: Creality Filament (PLA) for Prusa (mini) printers?

If the mini does ignore the K-values.. then why is there mini-specific templating code in a filament profile, prusa made?

perhaps we are missing something.