Hotend and Bed Temp Issues?
Hi all,
As shown in the picture below i keep getting this issue on my prints. It starts printing just fine on the first dozen or so layers, and then as soon as i walk away and come back i return to this. The extruder is gently clicking and whisps and hairs are coming out. This has happened 5 times in a row.
I think the issue is that the hotend is not actually as hot as the firmware thinks, which is supposed to be between 215C-220C. Also after heating the bed plate for about 20 mins it reads 55°C rather than the 60°C asked for. (Laser thermometer test)
Question: How can i determine if my hotend is too cold?
P.S. I have way more data i can share but there is a character limit
13 Replies
Hardware
I am running a V-Core 3.1 500
Revo Voron Hotend 0.4mm nozzle
LGX Large Extruder, dial set to 1 click, Direct Drive Setup
Prusa Slicer 5.0
Printing in Prusament Marble PLA at 215°C
Duet3 mini5+ RRF
revo isn't really meant for a high speed printer like vcore3. You are probably exceeding the flow rate the hotend is capable of
Im printing at 45mm/s, same speed as a prusa
I would look at what is different for those first layers then. Looks like it is having to go slower for the beginning layers because there's a lot more to print. Then it gets to those thin layers and probably the hotend can't keep up. Have you tried a higher temp?
What are your retraction settings? Looks like the nozzle is getting partial clogs... Maybe too much retraction?
botth good suggestions, ill run some more experiments tomorrow
I have seen similar effects with hotends getting too little air from the cooling fan. The melt zone extends up and finally the force required to push filament through increases.
i will investigate that, ive not gotten a chance to get back to the printer yet. I think the issue could be that i did not PID tune with the fans running full speed, so once the fan ramps up it cant keep the hotend hot enough
although i am cheifly concerned that the hot end is not as hot as the readout
@blacksmithforlife 🇺🇸 @sherbs ok all, my hunch was correct. i used a thermocouple and it read a consistant 200C when the interface read 220. this is too low for PLA which has a minimum range of 205, especially when the cooling fans turn on. But here is my issue. I am using the thermister settings e3d Suggests. which is:
M308 S1 P"e0temp" Y"thermistor" T100000 B4725 C7.060000e-8
I could try altering the beta value but idk
one source says the beta value should be 4267, another 4725, i have found neither to be accurate
I print pla at 195c 120mm/s... But, I'm using a rapido w volcano nozzle... What speeds are you printing at?
prusa speeds. about 45mm/s
i bumped the beta value from 4725 to 4800 and that seems to have fixed it
i dont know that it will be accurate through the whole spectrum of temps but it was accurate at 60 and 220
K... I'm not sure that's your issue but if it fixes your prints, so be it!
I will leave the solution as unsolved until i get through a few prints. I need to run a new PID and test with the new setting but, i have an early batch revo hotend and i had issues with my other one. None of the other root cause attempts solved the issue so im fairly confident this is it, though i envision i may have future problems with this hot end.
On my normal printers i’m at 220 on PLA, on the V-Minion the very same PLA role I’m going up to 240…I guess because I’m using a PT100 as a thermistor which seems to be less accurate than the ones on my other printers…and on the minion I’m using a double 5015 cooling fan too. Will probably run a new PID tune in the near future but so far it does well as it is.