calibrate extruder - different speed - different length

winsornewton

Hi,
I have ender 3 v2, duet 2 board, direct drive extruder.
I calibrated extruder for feedrate 6mm/s (G1 E100 F60) calculate e step value and printer works fine.

I tried print some model on higher speed with 0.6 nozzle and printed model looks underextruded. So I tried measure 100mm and extrude on higher speed 60mm/s (G1 E100 F600) and missing 37mm! I tried it more time and result was always same, missing 37mm filament to extrude.
Material was PLA, temperature 220. I tried 30mm/s feedrate (G1 E100 F300) and missing 7-8mm filament to extrude 100mm.

My question is, how setup extruder to working on slow and also high speed? where could be problem? Thanks for any help\

My config.g driver setup:

; Drives
M569 P0 S0                                         ; physical drive 0 goes backwards
M569 P1 S0                                         ; physical drive 1 goes backwards
M569 P2 S1                                         ; physical drive 2 goes forwards
M569 P3 S0                                         ; physical drive 3 goes backwards
M569 P4 S1                                         ; physical drive 4 goes forwards
M584 X0 Y1 Z4 E3                                   ; set drive mapping
M350 X16 Y16 Z16 E16 I1                            ; configure microstepping with interpolation
M92 X80.00 Y80.00 Z400.00 E426                     ; set steps per mm
M566 X600.00 Y600.00 Z60.00 E300.00                ; set maximum instantaneous speed changes (mm/min)
M203 X9000.00 Y9000.00 Z600.00 E6000.00            ; set maximum speeds (mm/min)
M201 X500.00 Y500.00 Z120.00 E1000.00              ; set accelerations (mm/s^2)
M906 X800 Y800 Z1000 E1000 I10                      ; set motor currents (mA) and motor idle factor in per cent
M84 S30                                            ; Set idle timeout

jay_s_uk

@winsornewton you should calibrate your esteps at the slowest possible feedrate, I tend to use F30 as the speed, that way pressure build up doesn't affect things.
F600 would be the equivalent to 10mm/s which in flow terms would be 24mm3/s which unless you've got something like a rapido or a dragon HF, you won't be able to achieve that.
what type of hotend and extruder do you have?

winsornewton

@jay_s_uk I have this https://trianglelab.net/products/dde-direct-drive-extruder?VariantsId=10109 V6 hotend
So I am on limit of hotend? And if I want print with higher speed I need new high flow hotend?

jay_s_uk

@winsornewton the limit of a v6 type hotend is typically 11mm3/s, which is just under 5mm/s (11 / 2.4 = 4.6).
You could look at a CHT nozzle (or a bozzle) and that would improve flow rate or you could look at a volcano hotend.

At 0.6mm nozzle size and i guess 0.3mm layer heights you're going to be able to manage around 60mm/s print speed.

This is a good page to have a read of https://ellis3dp.com/Print-Tuning-Guide/articles/determining_max_volumetric_flow_rate.html

winsornewton

@jay_s_uk thanks a lot!
only 60mm/s? First time I tried with 0.6 nozzle, layer height 0.36 and base cura speed 140mm/s.
Do you have some recommendation? change only nozzle or whole hotend? if hotend what you recommended? dragon HF or rapido or volcano or something different?

deckingman

@winsornewton The difference between a 0.5mm diameter nozzle and a 0.6mm diameter nozzle is only 0.1mm but if you do the maths, you'll see that the cross sectional area of the 0.6mm nozzle is about 40% greater than the 0.5mm nozzle. So assuming you use the same layer height, if you were printing close to the melt rate capability of the hot end with the 0.5mm nozzle, then you'll have to print 40% slower with the 0.6mm nozzle. If you increase the layer height as well, then you'll have to print even slower.

o_lampe

@winsornewton said in calibrate extruder - different speed - different length:

Do you have some recommendation? change only nozzle or whole hotend?

When you replace the heater with a longer volcano, your part cooling fan and the z-probe had to be lowered. But IMHO it's the easiest way.

Phaedrux

CHT nozzle upgrade can help the flow rate a lot without having to upgrade anything else.

deckingman

@Phaedrux said in calibrate extruder - different speed - different length:

CHT nozzle upgrade can help the flow rate a lot without having to upgrade anything else.

Glad you said that - when I bought my LGX-Ace/ Mosquito combo, I bought a CHT nozzle to go with it.

o_lampe

Q to @ll : How would replacing the Nema17 pancake stepper change things?
I found them pretty weak and heavy compared to the much lighter Nema14 round steppers (Orbiter etc.) So either live with the slower printspeed and use a lighter stepper or go for a full size Nema17 with extra grunt.