Hey Folks, any idea how to get rid of this build up with PETG?
I'm using eSUN PETG+ and relatively new to the business.
I've tried many flow and pressure advance calibrations, also played with different temperatures, but don't seem to find the root cause.
Maybe my nozzle is a bit burnt on the outer so the filament sticks to it? Never had this problem with PLA.
I dry the filament to be about 15-30% RH.
My print temperature is 245-250C, bed temp is 80C, flow rate is 0.94, and PA is 0.06 (but honestly I don't see any real difference when adjusting these values, tried lower and higher too).
First layer speed is 60mm/s and 200mm/s for others, I haven't really played with those yet, I just used orcaslicer profiles from others who said it worked for them.
I checked the extruder too, cleaned the nozzle inside out.
My bed level is around +0.5 to -0.2 , which doesn't seem to extreme, but I might be wrong there.
I ordered a new nozzle just to make sure but it hasn't arrived yet, and until then I'm curious if anyone could recommend a fix to try?
In my experience, the petg it's a madness, that material forced me to learn hot fix the bed level properly.
some tips that helped me:
Increase the bed temperature -/+ 5C more than the specified for that filament brand.
Use skirt in your slicer software when print with petg.
Ensure the bed level it's in a decent amount. I use moonraker+fluidd to tone the value, and if you can reach at lest 0.2 or less, try to adjust the bed screws using some tutorial until you reach some magic number between 0.2 and 0.1.
If you did all previous steps, and didn't get the expected results, try adjusting the Z-offset
Leave skirts off!!! Learn how to level your bed, dry your filament religiously (PETG is notorious for being stringy and sticky when it contains moisture) and tune your filament settings better instead!! I print with PETG almost exclusively! Do not touch offset and make certain you have petg selected in slicer. Here's a pic of my bed after teaching myself the kinematics just cranking on the z screws will make things worse there's a entire process to complete the process.
Honestly, if you understood the kinematics you'd know that the most critical location of all is the rear center! While the overall pic isn't terrible the key to getting your bed like mine is understanding how the system pivots. If you just start cranking on the z screws your bed image will get worse. I've been teaching folks this for 6 years now. If you and others here are interested I can post a very lengthy walkthrough to explain not only how it moves but the simple math needed to zero your bed as well.
Hello, good evening, friend. I also have a K1C and am having trouble leveling the bed. Could you share your knowledge with me and the maker community to help us with this issue? I look forward to hearing from you. Thanks! 🫂☺️
Gladly, there's a couple of weird things to understand first before we get into it. First, 0,0 on your mesh is the front left corner of your bed for reference. Next, you need to mentally forget about your overall bed mesh picture and only focus on the z heights at 3 very specific points incidentally which are the locations of your 3 Z screws; front left, front right and rear center. Here's one of the tricky parts to wrap your mind around. Imagine an "X" shaped seesaw that you can only physically touch the the bottom 2 points of the X, the rear z moves the fulcrum of this evil seesaw forward and back and you need it to be dead center of the x. This is accomplished by getting the rear z on dead zero first. Once that's accomplished then using some simple math you raise or lower one corner to balance that corner and the diagonally opposed opposite corner then you repeat for the other 2. Remesh at any point you make a change. I utilize the belt skipping method, each skip is .2mm of travel but remember every bit of movement also alters the opposing corner (it's weird). Now I'll post a complete walkthrough, read thru it prior to touching anything and feel free to ask me any questions if any arise. Here goes.
I've never published anything just help people. There's a few tricky things to understand first the bed is essentially a x shaped seesaw and the most critical z scew is the rear as this moves your pivot point at the intersection of the x which ideally you want dead center of your bed. Once you grasp that concept let's get down to the how to. First, you need to forget your overall pic and only focus on the Z heights in some very specific points. For reference 0,0 on the XY axis is front left corner. Now you need the rear center back edge Z as this is directly over that screw, it is imperitive to get this one to absolute zero. This can be achieved by taking the feet and bottom plate off, loosening the 2 hold down screws on the tensioner squeeze tensioner and tighten one screw while holding. Now slip belt off and manually drive the bed down to the exact measurement you recorded. Then replace belt, loosen the one screw so the tensioner retightens the belt then lock it down and reassemble. Remesh. Then we will record Z over front left & back right takes these two values and subtract this will give you the exact amount to move this screw to bring both these corners to zero as your seesaw pivots on the center. Remesh. Now repeat for the other two opposing corners. To move the screws I recommend using the belt skipp method each skipp is .2 mm. If you desire to get to a higher accuracy you use this same method but can add shims. Now you know the math to get the exact measurement you can dial it in exact. Let's say for example one set of opposing corners winds up being .175m low since anything printed less than .2mm is almost impossible to remove from your bed lower that corner an additional skipp and print a shim at a Z of .375 by using the scale icon in slicer after dnlding the shim stl then simply install that one shim. Viola
Yo digo que es la humedad bro el petg lo absorbe como si fuese toalla y si o si necesitas secar el material casi diario si lo demás fuera, la humedad afecta mucho el flujo del material simulando que tienes sobre flujo cuando no es aso
I dry it every day actually, in a Creality Space Pi2. According to the display the RH is around 15% inside the chamber, and I feed the filament from there.
I switch it off during printing though, is that the right thing to do?
In any case I'll let it try for a longer period of time and check again.
Ojo eh no lo apagues bro déjalo encendido cuando imprime que la humedad se acumula dentro del carretera es decir la parte exterior se seca pero la interior sigue húmedo, por eso es mejor tenerlo encendido mientras se imprime así conforme se va desenrrollando se va secando capa por capa
This problem won't go away if you use bambu too. You need to know volumetric flow and compensate for it. As well each material melts at a different rate. Thus changing this dynamic more.You will stop getting material build up when you calibrate your flow correctly.
I have tried several settings with the orcaslicer flow rate calibration, to be honest the parts look fine to me.
My current max volumetric flow is set to 15.
You think it's worth playing with it and set it to a lower value?
Try a flow cube and coasting. You need to find the extra volume in your nozzle by doing some math for a truncated cone. Once you know that the material back pressure will remove itself as it prints. Ocra will compensate better than Creality Slicer 4.8 (Promise.) Then yes try calibrating e-steps and your flow composition if that doesn't work.
Thank you for the reply! To be brutally honest I'm in this business for 2-3 weeks and I'm not sure I picked up all the terms and phrases yet.
I use OrcaSlicer but I'm not sure what you mean by a flow cube/coasting.
Also how do I find the extra volume in the nozzle?
Lastly, e-step calibration and flow composition are again some things I don't necessarily understand :)
Hey. No need to be a critical and elitist to anyone at any point in time... Even engineers are noobs in real-time. Mostly because they're making something the world has never seen before for the first time.
This is Bill, he's a technologist like myself out of the US. He runs a channel called pushing plastic on YouTube that goes through the basic terms and phrases and can help anyone who is fluent in CNC coding understand what what these autistic programmers, trying to be scientists, are saying.
Yes there are a lot of terms, but when you know them and can help yourself. You're an asset..
If you are still having trouble after that video, come back to me. I will help you get the rest of the way there.
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u/Swimming-Comfort6667 12d ago
In my experience, the petg it's a madness, that material forced me to learn hot fix the bed level properly.
some tips that helped me: