I’ve been trying to get my Overture PETG profile to work. I’ve started with the default profile from Bambu and modified it based on some comments in this forum. Some things have improved, but I still get globs of PETG at different places in the print.
I have modified the flow from 95 percent to 93 thinking there was over extrusion. Now I’ve dropped it to 91 and still have these clumps.
Have people gotten overture PETG to work right? What changes have you made to the profile? Here is a picture of what I’m talking about. The yellow is the clump, but the purple arrow shows some pretty rough quality too.
Doesn’t mean a lot. If the filament is soggy, it’ll take a while for the moisture to “cook off” and raise the humidity of your chamber (AMS?). Try drying it with a real dryer, undo all the changes you made to the extrusion parameters, and see how that does. I print PETG all the time, same as you starting from the BBL generic, with only a few changes to temperatures (in fact, I just did about 14 hours of PETG printing yesterday) and it works great as long as the filament is good and dry.
And also, like @stevesvd said, don’t use Grid Infill. Use Gyroid instead.
I am following the guide you linked…thanks! I’ve reset all the setting back to Generic PETG for the test model linked in the page. I forgot to change the infill as you suggested. I will do that next test. Before it even got to the infill, it did what is usually does and tore the first layer (yellow circle). You can see the filament that balled up on the tear on the bed (green arrow).
Meant to say, yes, I have a filament dryer and let it “cook” before printing. I don’t have an AMS, so I use a Sunlu dryer. It’s reading was the 10% after letting it sit in there for a few hours.
Yeah. I have Sunlu2 dryers as well. PETG goes in at 70ºC for a minimum of 12 hours. If I plan well enough in advance (I know I’m probably going to print something soon) I go for 24 hours. The process that drives humidity out of filament is very, very slow. More time is always better. And a full roll of plastic is a really good insulator that takes a while to fully heat up and heat evenly. You gotta stay in the dryer long enough for everything to get good and hot and then, long enough for the moisture to cook off after everything is good and hot. You wouldn’t put food in a food dehydrator for just a few hours and expect the food to be dehydrated. Same (or more so) for filament.
The humidity sensor in the Sunlu, like the sensor in an AMS, only reads the humidity of the air. Relative Humidity goes down as temperature goes up even though the amount of water in the air isn’t changing. So these humidity sensors are really kind of useless. The reading will go down just because the temperature is going up.
Thanks for the responses! I have weighed the spool and have put it back into the Sunlu2. I will check it in 12 hours and see what the weight is and do another test print with the same settings that I have now.
I have a baseline so I can start from here. I’ll report back in 12+ hours. Thanks again.
I have had the filament in the Sunlu for almost 24 hours. I have left it in the unit while printing too. I printed the test model as suggested in the calibration instructions referenced above. The print came out perfect. I decided to print some of the parts I have been trying to make and disaster struck. The first two part’s layers went down great. The third part tore up just like before. It’s like it’s hit and miss. I would normally think this is a bed adhesion issue, but I have success in this part of the bed some times. Other times it’s in another part of the bed. The same process is used each time on the bed. I use glue stick to hold it down.
I hate Overture filament, especially their PETG. I get all the same problems you are seeing, and I have tried everything to fix it. The simple fix is to use something else. I have had excellent results with eSuns new high speed petg. Try it! It has printed the best for me. Their regular petg is good too. SUNLU also seems to print fine.
I have had the best luck printing PERTG with the door open AND the top glass removed. Even when running the door open with the glass lid on, I have had issues. So the door opened, and the glass lid off on my X1c, which started getting better prints with PETG.
let me guess. P1 with regular stainless steel nozzzle 0.4mm? If so, my biggest suggestion would be to upgrade to at least hardened steel, or better yet e3d obXidian one.
The reason is that PETG tends to stick to the nozzle and travel along knocking everything on its way. Also, your overlapping infill doesn’t help here.
We have plowed through at least 36kg of Overture PETG without any real issues. Some failures early, but with new firmware and recalibration and flow dynamics on the X1C (multiple) we have had a ton of success. I don’t put much stock in the humidity deal. Only time I’ve seen this a real issue is with TPU and Nylon. I second with venting. We run draft prints a ton with the lid vented. No issues.
Overature PETG
Issue:
My first layer went down great, then terrible on the 2nd layer and above. Issue was that the PETG was not adhering to itself.
Solution:
Increase nozzle temp to 265 - kept at 245 for first layer
Slow printer down - 50mm/s first layer - nothing above 200mm/s - 100mm’s for important features, exterior perimeter
Run flow dynamics calibration - mine got me to .065 K value
Same… I didn’t even change settings, just used bambu petg basic, pushed the temp up a bit, and gave support a bit of extra space bc I hate dealing with support but my AMS has emotions.
