This is Bambu PETG-HF with default 0.2mm strength profile.
Filament has been dried for a minimum of 18 hours at 65c.
As comparison, the second and third picture is Eryone PETG-CF and is gorgeous so I cannot imagine it’s the printer. Did a full maintenance not long ago (100 hours ago).
You can’t compare with CF filaments, they generally hide layer lines very well. Looking at the HF one, it appears to start ok but gets worse as it goes up. I’ve had a lot of trouble drying one batch of PETG HF - it took a very long time to dry the inside of the spool - maybe this is also a drying issue. But your print doesn’t have any zits on the surface like mine did.
Maybe it’s just the lighting angle?
Seen it in person now. Granted, it doesn’t look as bad in person as it does on camera - apart from the, what looks like layer shift, just after the bridging finishes. But 18 hours at 65c should be more than enough … I am currently reprinting the same model using eSun PETG - let’s see how that looks.
Put the slicer view into ‘speed’, I’m not sure what the solution is but it’s definitely at that bridge / steep overhang after each level of holes. The flat areas don’t look the best either though.
For me using a lot of PETG-HF in black I went to 260C with the nozzle to avoid nozzle blobs and the project also had some weird organic overhangs and all these speed changes (from overhang amount and speed smoothing) on the layer were screwing things up big time so I just made it all very slow since i did have areas with greater than 50% overhang, didn’t have the option to just blast through it, but here?
I think I would set my overhang and bridge speeds to 100mm/s for all. I’m assuming that will work both for bridging top layers and any overhangs.
I went all the way down to 60mm/s to print and 10mm/s for bridges and overhangs …
I am currently trying some eSun PETG and it looks the same around those holes …
You say make it really slow but say 100mm/s ? Is that what you mean >?
No, I meant in my case it had to be slow in some areas of a layer but other areas of that same layer had little to no overhang so it wanted to go from very slow to very fast and the speed changes were killing the finish. So going with the lowest common denominator was my only choice.
But you don’t have such overhangs, the tops of those circles are 1mm at best it appears, so I would suggest a faster speed in the case of this model. I also almost suggest outer wall first but not sure that will work well with those overhangs.
It does concern me that its looking the same with the changes you made but make sure to use that speed view, im my case the coloring of the speed view matched the issues, easy to see the changes in speed were the source of the problem. You should verify that you see the same or similar.
Also, you might want to turn off the speed smoothing on the quality tab. If you attach the latest .3mf you are working with I can load it up here and take a look.
Appreciate your help. I have now tried PETG from eSun using the eSun profile downloaded from their website and it looks like &%# still … I did all the calibrations, even put a new nozzle in to make sure it isn’t partially clogged
I then run the Flow Rate calibration just to make sure, and that didn’t work at all. It essentially looks like an old Ender with too high of an offset and 50% underextruded. Completely failed.
Attached the 3mf …
The attached is the standard profile from eSun for both Filament as well as Process and the one change I tried here is basically slowing things down to 85mm/s because despite their process sitting at 150mm/s average, the settings specified on the website give a max to 100mm/s … Same issue.
As for speed - the speed is identical apart from the overhangs
But because of the slow down of the overhangs, the layer time is of course different. And it does look like the shift is shown almost identical to those lines
Box.3mf (1.2 MB)
I will try to set the bridging and overhang to 100mm/s as a test once the current print is done … Thinking back - I think I always had quality issues when a print has so many overhangs .
What I don’t understand is - even if I literally put every speed to 100mm/s and the speed is uniform …
The layer time still shows the changes even when I disable ‘slow down for overhangs’
The layer time is “how long does this particular layer take to print.”
I understand that part - but what affects the time and subsequently the quality. Basically every speed is set identical so I am trying to figure out what slows it down. I mean technically I don’t care what the settings are as long as I can fix the quality lol …
It’s not a speed issue, it’s a round hole issue. As it does the very difficult overhangs, it curls up a bit and gets caught on the next layer. Here is my PLA print - same thing. If I had a bunch of holes one after another, it’d just be a line too.
Yea I resigned to the fact that without supports, it just won’t be possible.
The filament is over extruding because it is slowing down for that overhang, it’s extremely obvious because it’s an overhang essentially for that entire layer all around the model - It’s looking worse and worse because every time you over extrude it’s making the height of the model ever so slightly higher than it should be… this builds up.
I don’t think your model will print nicely without supports or a redesign (or adjusting the flow when you slow down…)
My experience with Bambu’s “PETG” HF is that it is extremely finnicky about the temperature it prints at and over/under extrusion is it’s favourite thing to do because of it - However I think you’d have this problem with any filament in various degrees of success
I must say that I am disaapointed with the HF stuff. PETG-Basic used to be my go to but this HF - I can’t even get to stick on the Supertack … No matter what flow or temps.
I found by accident Eryone PETG-CF and that stuff prints like a dream. I mean yea CF tends to hide layerlines anyway - but this stuff looks almost like moulded
Sure, you won’t get a variety of colours etc. - but on Amazon they cost half as much as a Bambu spool … So for now - Cryogrip and Eryone PETG-CF … I might actually print a pot with that stuff and see what it looks like in comparison,.
Their petg-hf isn’t really petg as you know it (I’m not sure what is but it aint petg!). Applying any petg printing experience to it isn’t going to help much.
Petg-cf is great if you want good visuals - Just print what works best for you. I see no real value in using the HF stuff. (I think it looks better than normal petg but I’m not using petg for visuals most of the time)
Just a shame they removed the basic stuff …
