I encountered some minor issues while printing with PolyLite PETG. When my nozzle starts printing the first layer, the first approximately 1cm often fails to stick to the bed, and the parts printed in the upper right corner also consistently have noticeable defects. Additionally, when I print cylinders, the inner walls always experience under-extrusion. Does anyone know why this might be happening?
I have already dried the filament and cleaned the print bed. The PETG settings are the default ones. The first layer wall speed is 50mm/s, and the infill speed is 105mm/s. K=0.049.
First, Kudos for starting off with the basics and printing a first later test. This simplifies diagnostics immensely.
I personally do not trust the default filament settings. I’ve found they’re a good jumping off point but not acceptable for really dialing in the right parameters. You may want to simply recalibrate.
However, I am still bothered by the fact that you’re getting 3 different results and that shouldn’t happen. So perhaps there’s more going on than just filament calibration.
My first question is: have you tried bed leveling before the print?
While I don’t believe that’s the root cause, we would want to rule it out. I ask because of the obvious pronounced difference between the upper right hand corner sample and the others.
The second question: Have you tried to print a single 100x100mm sample to see if it produces a similar result?
What we’re looking for is if this is an extrusion issue. If you get a uniform ‘weakening’ of the 100mm sample in the upper right corners. That points more to a filament calibration issue. I would then consider doing a max flow rate test in Orca or simply dialing back the max flow rate in the filament profile and re-run your test. Default is 13 for Bambu PETG but try dialing it back to 10.
The other trouble shooting step I might take is to use a 100x100mm sample. However, in a second test. Change both the orientation and direction. Here’s how that would look in the slicer settings under Strength tab.
If the thinning out of the filament occurs on the opposite corner, this would be a strong indication of a flow rate problem because that indicates that the filament flow is running out by the time the nozzle reaches the end of its stroke.
I dried the filament again last night, 55 celius degrees and 12h. I also did the bed level calibration today. Also cleaned the bed.
I actually use PolyMaker Polylite PETG. But i still tested the maximum volumentic speed. I actually dont see problems until 15mm3/s. But i still set it to 10mm3/s before the printing.
I printed 100mm x 100mm, the resault was pretty good.
So i tested 200mm x 200mm to check if it stays so at the corner. Then the problem shows up again. But this time in different places. upper left corner and under middle.
OK. Thanks for posting clear images. It helps a lot. As far as not having the same settings in Orca, I am on the Beta 2.1 version but I’m willing to wager that you have developer mode turned off. That setting is found in preferences and it gives you access to all of the setting.
Before we go to far though. You may think your plate is clean but the larger first layer test says otherwise which is why it is such a great test. You have lots of contamination on your plate. It shows in the picture below. The roundish spots are most likely due fingerprints. You’ll want to take some degreasing dishwasher detergent and wet the plate under running water. Then spread the dishwashing detergent evenly on the plate. Then take hot tap water and let it wash away all of the soap. This will ensure that you actually have completely degreased the plate.
Since you said you already set the max volumetric flow down to 10, that should rule out flow rate - I hope. Try kicking up the nozzle temperature by 10-20 degrees in 5 degree increments.
Two things I might also suggest. First, use bed leveling on the next print just to rule that out. But my first suggestion is to try turning up the flow ratio. Use a number around 1.05. While that’s kind of extreme, what we want to see is if it changes the flow significantly enough to close up those gaps. If it does, then start dialing it back to a lower level that you achieved when you did your flow rate calibration.
It’s in the filament settings just in case you forgot.
Alternatively, but not to be used together, you can up the flow ration in the slicer parameters. It’s under the Quality tab. This will change the amount in the Gcode globally. Start with the Bottom and if you see no affect, change it back to 1 and then try the top surface flow ratio. A good number is between 1.05 for a boost in flow and 0.95 for a reduction in flow.
Hi, I also have trouble with PETG on my X1C so I hijack a bit if its ok.
Problems according to picture, 3 walls 15 infill and standard speed. In low speed it goes fine and I have managed to print this part before in standard speed. Any ideas what the problem is? Processing: 1000007538.jpg…
