Choppy Infill layer using PETG
I am printing this with PETG at 245 degrees. The infill here is 25%. If you look closely at the infill you will see gaps making for a rough surface. The printer works fine when just doing a typical layer. It started this at 240 so I thought it might be too cool for printing. This was sliced for Quality speed, .4 nozzle, Generic PETG setting in PrusaSlicer. I'm using Numakers Filament. I normally use 15% fill and haven't seen this with the less dense fill. The humidity in the here is usually <20% so I don't suspect wet filament and the normal layers print fine. Anyone have a suggestion on what could cause this? The print is still usable but I would like to get a better infill layer.
RE: Choppy Infill layer using PETG
I've not used that particular petg before but I'd try it at 245 or 250. See if you can do a small test object to confirm, like an xyz calibration cube so you don't have to wait to find out. I'm curious what you're results are. wow, less than 20% humidity! I'm here in colorado and my man cave hovers about 22-24% in the winter.
RE: Choppy Infill layer using PETG
Thanks,
I'll give that a try next chance I get. Luckily the print didn't stop the nozzle, just made a lot of noise. End print worked. Southern UT is pretty dry. Most of the time it's around 20% but my indoor weather station says 19% and outdoors is closer to 40% at them moment.
Doug
RE: Choppy Infill layer using PETG
if you're on an iphone, you'll need to save the .heic file as a .jpg or .png to upload here. it's annoying. the other problem I tend ot have with some petg is that the default extrusion multiplier of 1 is sometimes too high. I have a few filaments that require it to be .97 or .96 or else it blobs. Try 255 and see if you can upload a picture here. Are you using input shaping profile for the MK4. I don't personally use those yet for either for my XL or my two MK4 printers. If you are using IS profile, I'd try slicing and printing without IS turned on.
RE: Choppy Infill layer using PETG
Here are the photos I took. First photo is done at 240 and the second is at 250.
RE: Choppy Infill layer using PETG
I'll take a look at the extrusion multiplier next time I have a project like this. I didn't slice this with IS. I've found slicing using IS really decreases the quality of the print and usually I'm not in a hurry to finish the print. I don't do this for money so I only have the MK4. I was originally looking at buying the XL but didn't want to wait. Now I'm not sure I'll buy one. It appears the market is changing a lot with newer printers such as the Bambu. Don't like the company but I am pretty impressed by the printers they are making. A friend bought one and for a lot less than I paid he got a printer with an enclosure. Thanks for the advice!
RE: Choppy Infill layer using PETG
I've never had to go UP with the extrusion multiplier for petg, only down. Prusa is what I know so I'm hesitant to go with anyone else. I like the open aspect of it. I'll agree that prusa's antics as of late have really blemished their rep, but I'm hopeful they'll learn from this... Maybe the XLS or XLS+ will finally deliver. But to be honest even with latest slicer and firmware it's improved dramatically since I got it. I just wonder where the extra time "testing" was spent when there are simple things like the lack of a PVA option in the load filament menu on the printer....
RE: Choppy Infill layer using PETG
I solved the problem. I turned the temp up to 250 and it got a little better. I ended up changing the nozzle and it completely eliminated the issue. I could probably turn the temp down and it will still be good.
RE: Choppy Infill layer using PETG
interesting, I hadn't even thought of that. nice
I solved the problem. I turned the temp up to 250 and it got a little better. I ended up changing the nozzle and it completely eliminated the issue. I could probably turn the temp down and it will still be good.
RE: Choppy Infill layer using PETG
Nozzle probably had over 2000 hours on it. I printed about 3 spools of matte PLA which may have sped up the demise of the nozzle. Lesson learned!
RE: Choppy Infill layer using PETG
Makes sense for sure
RE:
The default infill speed is too fast for some PETG. It looks like your under extruding to me. This is why everything else is printing fine besides your infill.
I have run into this depending on the filament manufacturer. The recent Prusa slicer settings update have slowed down the infill speeds. It's always the infill that was the issue.
The way you can control this without messing with the print speeds it's to set the max volumetric speed in the filament settings under the advanced tab. Look up the recommended print speeds recommended from your filament manufacturer. It varies quite a bit. For example Hatchbox PETG is 100mm/sec while Polymaker is only 50mm/sec. You have to do a little math but here's the formula. Volumetric flow = print speed (mm/sec) x line width x layer height
RE: Choppy Infill layer using PETG
Thanks for the info. I'll keep that in mind. I'm still fairly new and truthfully never really considered things like volumetric flow. However I printed another copy of this with a new nozzle and it came out perfect.
RE: Choppy Infill layer using PETG
yeah, MVS is a great tool to control the flow. I've been using this recently to dial in my tpu prints.