RE: MK4 Warping seperation
I think I disagree with some of your statements.
If there is a gap between the heated bed and the thermistor, the actual temperature (measured with an external device) should be higher than the thermistor-reported temperature, as the bed should heat more for the thermistor to notice.
You are right in which the environment has some effect, and if any of the other printers I have in the same room all the sudden started to show the same problem, I would more than happy to raise the bed temperature until nicer weather comes along and room temperature is higher. This has not been the case, all my other 8 printers print perfectly fine with the same settings I have been using for the last 7 or so years. Bed temperature for PLA has always been 60°C. The mk4 is the only one among them which fails.
I am not comfortable thinking "ok, it sucks, I guess I will have to set the bed temperature to 70°C for the mk4". Sorry, but no. To tinker with I have other DIY printers which I set up from the ground up. All the profiles for PLA on PrusaSlicer have a bed temperature of 60°C and I don't want to tinker with profiles. Again, it would be a whole other thing if this problem showed up on other printers. I spend a good chunk of money for the mk4, I just want what I thought I was paying for. Nothing more.
RE: MK4 Warping seperation
If you measure directly on the pcb of the heatbed without the sheet, you are right, the bed temperature should indeed be higher since there will always be a temperature gradient between heat source and sink. On the surface of the sheet it can go both ways -- it depends.
I see your point. I have only the MK3S, upgraded to + and can happyly print using just the default profiles without having to tinker at all for PLA, PETG, ASA, FLEX and other filaments. OTOH, over the years, some users with way more experience reported that the actual surface temperature (on an MK3S+) can be up to 10 degreees lower than displayed. Yet, if I had any real issue like you, I also would insist on have it ironed out. Especially, if the printer is surrounded by other, potentially way cheaper ones that just work. I use Prusament PLA, PETG, ASA, PC-CF. The FLEX is filamentum. With all those, I never had do change bed temperature. Same with the 2 MK3S+ we have at work. There I have colleaques which only very basic knowledge in the printer. Yet they just print. Did you get the printer assembled or did you order the kit? I wonder what the surface temperature of my print sheet atcually is. When I find the time, I can try to measure it. I briefly considered, whether this may be a firmware thing but I doubt it. One can always try a factory reset.
I assume, that you already checked obvious things like unplugging and replugging the thermistor cable off and onto the board.
I agree with you that it is unfortunate, that support did not just send you a thermistor -- given your experience and the facts you reported. That would have been the cheapest, least frustrating and least time consuming thing for you and support. In a way, they are victims of their own success. They had to ramp up personnel including for support. As it seems, at least some of them are still lagging in terms of knowledge and reasonable behaviour towards an experienced customer struggling with their product.
RE: MK4 Warping seperation
No. I'm an old man (68) and not all that familiar with the many different ways people communicate today. I am willing to give it a try.
RE: MK4 Warping seperation
My last post was rather adressed to @FelixH. Sorry, that I did not made it clear.
In your case, you might give cleaning the sheet with dish soap and rinsing with hot water a try. Then try to print while avoiding draft.
RE: MK4 Warping seperation
Hi, just to update, i replaced last night the heatbed thermistor, and now the reading is much more accurate. I measured the resistance of the thermistor and the difference was around 20k Ohm in the room temp, so the "old/broken" had around 103k Ohm, while the "new/working" 80k Ohm. First print tests, and reading with pyrometer, and thermal vision camera showed the drift around 10 degrees, not 20 like before, and in higher temps, it's better.
RE: MK4 Warping seperation
hello just found this post as i recently face to some warping that i never ever had!! pla petg, asa no problem i change the nozzle with the obxidian !! supposed famous !! and now all print are S....even simple pla on satin pei sheet !! tomorow i run a new test with my previous nozzle and adapter !!will see but it's weird i don't think it's bed as well as T° nozzle i tried to tinkering and same
RE: MK4 Warping seperation
An update from my part... after many tests and back and forth with the support staff, I ended up sending the printer back for a refund out of frustration. I just did not have enough patience to deal with it any longer. They sent me a new bed thermistor and it did not make a difference. I even tested the bed temperature by attaching another printer's thermistor on top of the build plate. The readings of the mk4 and the other thermistor matched perfectly. So I concluded the bed temperature was not the issue.
I run a very last test out of curiosity which was simply turning off the part fan. And, what do you know, it worked perfectly. At this point I was already decided to return the printer. I am convinced some of the part fans are out of specs and are "too powerful" they cool down just to much so that the PLA begins to warp. A posteriori that matches my observations. Before I noticed the warping I just printed larger surface parts in which the fan didn't stay for long on a single spot. In those cases the prints were perfect.
So here is my suggestion: try these two tests. In one you print a small part with the part fan turned off and on the second test, print a larger part, which occupies much of the bed (it could be smaller parts distributed on the bed). Even though I am not a Prusa customer any more, I am really curious about it.
I ended up switching brands. My new printer delivers excellent prints and I haven't have any issues since I got it.
RE: MK4 Warping seperation
humm i did read ur comment before but really how come a printer do so much warping i never have this so bad issue w my mk3s ok i modify lot of part and do the Z myself but and even on the mk4 but w a adaptor and hard nozzle , that was perfect i print ASA no prob and no enclosure and now w this Sh..e3d nozzle i can't print o'll run other test tomorrow to see if it's like before then the answer is easy if not than i am in big trouble ..
i understand ur frustration but many ppl are using the mk4 without any prob the new cell force should be good ..THX for the test and good for u to switch and happy w other brand..
RE: MK4 Warping seperation
@FelixH: Thank you for the feedback. Happy printing with your new machine.
RE: MK4 Warping seperation
Hi Guys ,
i've got a solution for the "warp" effect on PLA that works absolutely fine for me. I'd like to share this with you.
This was the Problem:
Well, I bought my MK4 in January 2024 and i'm quite familiar with PLA. On my Mini+ most of my Prints were in PLA Material and im quite happy with that Material.
Ok , so i did my first Prints and ofc i totally ran into that "Warp Problem" with PLA. I did a few Prints, then i started to search for Information and Help Online.
I couldnt find anything that worked for me... I checked the X and Y Axis Belt several Times. No Problems here. I tried PLA from diffrent Sellers - Still warping.
Firmware updates -> Warp. But still only with PLA , my MK4 did perfect Prints on PETG...
I Have no Enclosure , but my MK4 is placed next to my Mini+ that does just zero Warping on PLA.
Warping Solution thoughts...:
Well , im not an Expert in 3D Printing , Slicing and 3D Design but im an Engineer and im able to take a look at things technically.
Since i've never had any "warping issues" with my Mini+ i simply compared both printers. I left the Print Enviroment aside at first since the Mini+ has the same
Conditions without problem. But, one big Difference is, that the MK4 got an extra Fan to cool down the Print.
So somehow i thought - this Fan could be the problem.
Alright so i switched my Slicing settings, No Fan for the first 5 Layers - then +10% each layer up to a 100% for the rest of the Print.
What happened ? Extreme Warping from Layer 8 or so untill the end ... OK - at Least the Problem changed Behavior somehow.
So that Fan is definetly somehow responsible for my Problem. I switched around the Seettings for a little Bit got some better and worse prints...
But finally i got these Settings:
- No Fan for the first 6 Layers
- Until Layer 10 , +10% for each layer = Layer 10 - 40% fan speed (Max speed for the whole print)
- Temperature - Heat Bed 70 degrees (since that thermistor issue you have like 60-63 degrees in reality)
Now i dont have any Warp anymore - even with extra Wide Prints its perfectly flat on the Headbed and you get a perfect first layer...
Just my 2 cents , good luck you all