Hello
High flow hotend slower than normal
I tried more filaments but usually calculate longer print time when I set high flow hotend instead normal hotend
Only Bambu hf pet-g comes 2 minutes faster 13:08 vs 13:06
Here are samples:
First print time Normal hotend
Second print time high flow hotend
Generic hf pla 13:30 vs 14:01
Generic pla 16:31 vs 16:54
Generic hf pet 14:04 vs 14:27
Generic pet 16:31 vs 16:54
Bambu hf pet 13:08 vs 13:06
Bambu pet 14:43 vs 14:56
I’ve noticed the same thing! The high flow nozzle option almost always prints slower than the standard. Also, I notice the PETG HF settings print slower than the PETG (standard) settings. Looks like I wasted money on the high flow hot end!
Only selecting the HF hotend doesn’t mean you can print faster - unless you use Bambulab filament profiles. Generic filament needs to be set up for high flow printing, usually by doing a max flow test in the calibration tab.
For example, standard max flow rate for generic PLA is 12mm³ with standard and HF hotend - your nozzle doesn’t matter, since your flowrate always limits your speed.
For reference, I tested some cheap PLA on my P2S and get around 34mm² with 0.4mm standard nozzle – there is even more headroom with the HF hotend.
By setting the correct value for your filament in the filament settings (there is a tab for standard nozzle and HF nozzle values!) you will see time benefits – if the print speed is set up high enough of cause.
I would argue, a 0,4mm HF nozzle is not worth it – you need crazy high speeds to get to a flow rate more than 30mm², which the standard hotend is already capable of. But it does make sense for fast printing with 0.6 and 0.8 nozzles.
Personally, I use standard 0.4mm and 0.6 mm nozzles with a max flow rate of 30mm³. Thats fast enough for me.
I have the same issue with my X1C, for example I have a build, that takes 5hrs with 0.4mm Nozzle, standard flow and PETG. When I change to high flow, also with an extra faster PETG profile with higher volumetric flow, it takes over 12hrs…
I checked all parameters in Bambu Studio, when I change from standard to high flow, Bambu Studio increases the layer speed for outer and inner walls, infill, top surface and 100% overhang speed, nothing else.
I don’t have any idea, why ist so much slower with high flow…
when I print it’s really very slow…
please find the bug !??
