PLA overhangs are utter mess
OK. Dunno what I'm doing wrong. But this is what I get from overhangs. 200C, 60C bed, 4028 fan on 50% overhang printed at 33mm/s
Any questions, anything, I can add. please, shout ..
It's like the PLA "doesn't stick" ..
34 Replies
fascinating-indigo•8mo ago
Would be great to have better pictures, I can't figure out anything on the current ones
First one is vertical wall, isn't it?
I'll post better ones. Yep, the first is outer wall, so effectively "top surface", second is inner wall, so "overhang" if you will, though the slope is 45deg ...
fascinating-indigo•8mo ago
Ok, if I understand correctly, the issue with wall angled 45 (or so) degrees to heated bed, it is bad both inside (overhang) and outside (external perimeter). Is that correct?
Hot thick this wall? Home many perimeter? Can you show it in slicer?
correct. four walls on the slope. the overhang one has fan turned on..
part of the slope for reference
fascinating-indigo•8mo ago
Outer wall first? Can I get the link for the model? Interesting to check it in the slicer. Overall, this design must be problematic, I would try to crank cooling to maximum
I tried both inner-outer and outer-inner. Inner-outer turned out tiny bit better. But 💩 nevertheless.
https://www.printables.com/cs/model/296322-v-core-3-12038-static-cooling-fan-mount
Printables.com
V-Core 3 120x38mm Static Cooling fan mount od autora NecroDavid | S...
120x38mm static cooling fan duct for Rat Rig V-Core 3/3.1 | Stáhněte si zdarma 3D modely ve formátu STL
I'm trying now with https://discord.com/channels/582187371529764864/878965315596349490/1133613346818629714 as a test. starting at 200C, 60C bed. 30% fan on all the time, ramping up to 50% for overhangs, 5 second run-up, 0.2 sec kickstart. The rest is Orca defaults for RR500. Wish me luck.
Same thing.
I'll increase the fan speed next. But I find it ridiculous. Compared to my i3 it blows million times more, prints the overhangs at even slower speed and this is the result 😔
Lower the temperature a lot just to make sure it is not that...
190 fan 50; 190 fan 70; 200 fan 80 😠I can't believe I have to go full blast on PLA at these speeds. At full tilt, fine, but at 11mm/s on overhangs ?? Disappoinment barely describes.
fascinating-indigo•8mo ago
What speed you talking about?
How fast plastic cools is not about speed, it is about layer time
11mm/s for overhangs. the rest is default..
in fact, here's the settings.
You reckon this could help https://discord.com/channels/582187371529764864/951978948718366730/1027181257341276181 ?
here's the speeds from slicer:
what speeds are you printing at, if I may ask?
fascinating-indigo•8mo ago
Have you tried different filament?
It might be filament in part I guess. I just tried printing at 80-100 fan for anything over 30deg . It looks decent then. I just find it ridiculous that I need such a volume of air for PLA. Sadly, with the results, I'm considering CPAP 😒
I'll try with different filament tomorrow. But don't have any other brand at hand, just different colors. Have some on order, so I guess I'll have to wait for concrete results a little longer.
OK. filament brand makes no difference. Unless I go full blast on PLA overhangs they look horrid.
same issue
did you get aroudn this ?
i find it hard to believe that a 4028 is not able to cut it and yet i'm here
In the end I changed the original nozzle for the one with extra flow. Made all the difference. Now it's presentable. Still, have to admit, I was expecting little better. One more thing I changed. Clumsy hands killed the killer fan it came with, so I changed over to Arctic 4028. It's much quieter, so it can run at faster baseline speed without too much annoyance. Full blast speed is lower, but honestly, I think the original fan is a bit overkill at the top end.
Oh. And one more thing. Ticking that Classic Mode box sometimes helps. Sometimes being the key part there..
i have a high flow nozzle already lmao
i dont understand how a high flow nozzle would help with overhangs
Fan nozzle....
wait
whats a fan nozzle
you mean the duct ?
are you using the tri horn duct now ?
There you go
Words
😂
haha its aight
trihorn duct right ?
Brainfart on my end. Sorry.
if not do link me to something
Correcto mundo.
Tri horn is the thing that i believe did it for me. Through i did change the fan at the same time. But again, it's gone down in volume and speed, so that shouldn't be that...
one thing that i'm considering is fan "lag"
sometimes your fan wont go to max as its demanded
setting a global max might help test this theory
You can set spin up time in slicer, so it kicks off before it needs to
oh wow
what's your spin time ?
3sec. Just to be on the safe side
Measured just under 2...
just curious
what's your hotend extruder combo
and pressure advance value
i used to use rapido + orbiter. now using v6 volcano (copper) cht + orbiter
Lemme check.. like i remember 🤣
Rapido and Lite Bondtech
So, yeah, you're probably pushing little more than I do
I have max set at 25mm³, then it starts skipping like mad with PLA at 230..