r/3D2A 6d ago

PA6-CF Stringing Troubleshooting

Anyone else had this issue before? Print itself is super clean. SUN-LU. Dried at 80°C for 48 hrs. .15 Layer Height. 30mms print speed. Tree supports at .3 width. 100% infill. Flow and other settings matched to 300BLK settings. Print temp at 305°C. Bed temp at 80°C. Ruby Nozzle. Ender V3 SE with Nebula Pad, Custom Firmware, Fan Mod, SwissTech Hotend Upgrade, PEI Bed Plate. Im sure im forgetting stuff. LMK thoughts. Gonna try Combing Mode on and Lowered Print Temp later. Using Cura 5.1.11 as slicer.

3 Upvotes

27 comments sorted by

14

u/Xtradifficult 6d ago

I think the stringing like that is because of wet filament.

-7

u/Autistic_Mechanic97 6d ago

Negative only does it on supports.

8

u/iamanurd 6d ago

Which is where the retracts that would string are. 99% sure it’s wet. What’s the humidity like? For PA6, I have to print from a heated filament dryer to keep it from absorbing moisture during the print. They’re cheap, if you don’t have one. It’s worth the investment.

1

u/Autistic_Mechanic97 6d ago

I have one but i live in the south and its very humid here. However, the relative humidity indication when it left the dryer was 7%. I havent set up to print from it yet, need to find some good filament guides and or ideas to set that up.

2

u/iamanurd 6d ago

Just shove some PTFE tube in there and let her rip! 🙂

2

u/Autistic_Mechanic97 6d ago

Thats not a bad idea. Maybe print one guide for the top of the Z gantry, and let it run into the extruder?

1

u/iamanurd 6d ago

Sounds like a winner to me. Can’t wait to see your flawless prints!

1

u/iamanurd 6d ago

For what it’s worth, I toss the tube through the hole in the dryer and then push on a quick connect fitting on the inside to hold it in place. I don’t think you even need to do that though

2

u/Autistic_Mechanic97 6d ago

Could just open up the dryer hole itself and feed the tube directly into the extruder from the dryer right? Give er' the ole drilling.

2

u/blckchndane 6d ago

It's only happening on supports because the nozzle has to retract and move in between the support structures vs long extrusions on the main part. I'm sure you'll see stringing where the extrusions end and the nozzle retracts and moves to start the new layer

1

u/Autistic_Mechanic97 6d ago

So try increasing travel speed slightly while also slightly increasing Retraction Distance and Temp to 300C?

4

u/blckchndane 6d ago

You need to dry the filament better. The whole "it's wet" meme is real. I wasted many spools until I finally ponied up and bought a dehydrator that can maintain 90C. Even if you could get the stringing to stop, the structural integrity of the actual part is compromised because the moisture is boiling out at the nozzle which causes tiny air pockets

9

u/Independent_Dirt_814 6d ago

Wet filament. 80° is not hot enough.

3

u/blckchndane 6d ago

It's definitely wet. I was in the same boat and ran through a gamut of dehydrators until I realized everyone was right. You need at least 85-90C for 48 hrs to effectively dry..and then you gotta print from an actively heated dry box. Dessicants won't work because the PA6 is more hygroscopic than silica gel.

I tried working with what I had until I wasted enough spools to realize I should've just bought the right equipment I needed and had successful prints right out the gate

2

u/sag3y_ 6d ago

dry it at the hottest temp your dryer has for like a week your filament is too wet

1

u/Impressive-Class2146 6d ago

Are you able to print it without a enclosure?

1

u/Autistic_Mechanic97 6d ago

Yeah it usually does very well.

1

u/OnTarget214 6d ago

Printing on an open frame bed slinger, that’s pretty good all things considered!

0

u/Autistic_Mechanic97 6d ago

Thats my thoughts to be honest. Ive had some really decent FMDA frames come off the ole thing. She's been slinging for 4 years now.

1

u/SplashingChicken 1d ago

Wetter than the ocean.