Hello All,
Any Idea on what the Issue is here ? The filament is Sunlap PA-CF printed with generic PA-CF settings.
It was heated 8Hours 80 degrees C already nothing changed.
Best Regards
Alex
Is your filament dry? Excess moisture in the filament can cause this.
I had it already for 6Hours at 80 degrees C. Should I give it another 12 Hours at 80 degrees ?
Sounds like that should have been long enough, but more time might help. You spool could interfere with drying if it is solid and doesn’t allow the heated air access to the filaments from the sides.
Here is one link I found that might help you with the issue…
Tried anything without success. Still the same picture. Any other idea ?
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Only other thing I can think of right now is to try a different spool of material. Maybe try putting it back in the dryer overnight.
Did you ever solve this issue?
I’m getting the same problem with certain filaments and not others.
PolyMaker PA6-GF (glass fiber filled) - Yes
PolyMaker PA6-CF (carbon fiber) - NO, prints perfectly (same exact settings as GF)
3DXTECH PA6-GF30 (glass fiber) - NO, prints great
SainSmart Nylon+ (carbon fiber) - Yes
I have a feeling that this issue is retraction-related. When I have time I plan to start experimenting with retraction settings but frankly I don’t like the way they have to be configured in Bambu Studio.
Could be retraction settings. I had issues with blobs printing the Prusa Batman model with PA-CF when my retraction was too much, changed it from 3mm to 1mm and the blobs went away. But that part has more that blobs… it’s has plastic smallpox lol. Maybe z-hop settings?
Strange that you had issues with the Polymaker PA6-GF. I tuned in PA12-CF and used the same settings for PA6-GF and had no issues. I only did a minor test print though since I don’t have a mount for the massive roll.
Yeah, I used the EXACT same settings for PA6-GF, PA6-CF, the 3DXTECH stuff, and the SainSmart stuff. I figured nylon is nylon is nylon, right? Obviously not. 
I’m really baffled that the PolyMaker CF and GF produced such disparate results with the same settings.
I’m going to experiment with retraction settings (and maybe Z-hop) sometime next week, I hope. I’ll post my results if I find anything.
For the record, initial Z-hop and retraction settings in my Bambu Studio Printer → Extruder settings are -
Length: 0.8mm
Z-hop when retracting: 0.4mm
Z Hop type: spiral
Retraction speed: 30 mm/s
Deretraction speed: 30 mm/s
Travel distance threshold: 1 mm
Retract on layer change: y
Wipe while retracting: y
Wipe distance: 2mm
Retract amount before wipe: 0%
OK, after a bit of websearching the implication is that these artifacts are potentially a result of insufficiently dry material.
I don’t see how that’s a problem as I dry my material at 80 degrees C for 8 hours in advance of printing - and where I live the ambient relative humidity is usually around 10-15%, though today is a boggy 25%. 
I’m going to re-dry all the material at 90 degrees C this time and see what happens…
I was wondering if that might be the issue. Given how similar Polymaker’s CF and GF filaments are to each other, one wouldn’t expect to need different print settings. Has your GF been open for awhile? Mine was only open for a few days before using it to print and I keep the AC rocking in my place so it doesn’t really ever get humid.
Nope, when I open a spool, I give it a thorough cooking, and stick it straight into the AMS. Unless my AMS is raining inside (quite a trick in the desert), I don’t see what/how I could have gone wrong.
Well, after 12 hours at 90 degrees C the SainSmart Nylon+ is printing well, without weird artifacts. I guess the extra drying time and higher temp was needed?
Before we celebrate, please let us all observe a moment of silence in memory of the spool for my Taulman Glass Fiber Alloy Nylon. After sharing space with the SainSmart Nylon+ and the 3DXTECH in the dryer, the spool looks like a cooked lasagna noodle. Time to print a spool-to-spool transfer gizmo. 
Yeah, that’s actually good advice for anyone else looking at this. Every brand filament, even of the same material, can be different in many different ways, including drying temperature and time. Unfortunately, many lower cost vendors just print the same number they find online and don’t bother checking themselves.
I’ve noticed that among PVA materials the same thing is true, different brands will need different temperatures and times for drying, and the behavior can be radically different from brand to brand.
Whenever I run into this problem with a new, uncommon filament, if you’ve already dried out the material at the standard temperature for at least a few hours, I’d always up the temperature by 5-10 degrees rather than increasing the time. Time hasn’t ever really made a huge difference (except when maybe I’ve left something in the oven for many days) - temperature is far more significant. The only risk is if the manufacturer doesn’t give a time, or if it’s higher than spec’d, you may end up damaging the filament or the spool. Some brands of filament are just not well designed and cannot tolerate picking up any moisture at all in practice.
I have even found that some PLAs benefit from longer/higher temperature bake-outs. In some materials the bubbling and boiling only shows up when you are printing at higher than typical temperatures (helps for layer adhesion), but can go away with a higher temp bakeout of the material
I don’t print anything fancy like this, my dryer has a hygrometer on it. I’ve had CF-PLA come out of a package at 48%. I just leave the stuff in the dryer until it reads under 22% (if I can I try to get it under 20%).
Those numbers might be inaccurate as I’ve never tested or calibrated them for accuracy, I just know if the dryer reads under 22% after several hours… It’s good to go.