initial movement speed crashing Z axis
I have a i3 clone running a ramps board with Marlin 1.1.8 and TMC2130 SPI stepper drivers.
I have been using Cura and dont have any issues but wanted to try PrusaSlicer.
the initial movement is
; generated by PrusaSlicer 2.1.1+win64 on 2020-04-18 at 16:42:06 UTC
G1 Z0.220 F7800.000 <-- this is too fast for my printer and i need to adjust this setting to be able to even start a print.
Where is this speed setting? I have set all the machine settings to match those in Marlin firware but that speed is not changed.
I have set the machine limits as per the settings I have in marlin and it makes no difference.
And the resulting GCODE:
; generated by PrusaSlicer 2.1.1+win64 on 2020-04-19 at 07:55:03 UTC
; external perimeters extrusion width = 0.45mm
; perimeters extrusion width = 0.45mm
; infill extrusion width = 0.45mm
; solid infill extrusion width = 0.45mm
; top infill extrusion width = 0.40mm
; first layer extrusion width = 0.48mm
M201 X1000 Y1000 Z20 E5000 ; sets maximum accelerations, mm/sec^2
M203 X500 Y500 Z12 E120 ; sets maximum feedrates, mm/sec
M204 P1500 R1500 T1500 ; sets acceleration (P, T) and retract acceleration (R), mm/sec^2
M205 X8.00 Y8.00 Z0.30 E3.00 ; sets the jerk limits, mm/sec
M205 S0 T0 ; sets the minimum extruding and travel feed rate, mm/sec
M190 S50 ; set bed temperature and wait for it to be reached
M104 S200 ; set temperature
G28 ; home all axes
G1 Z5 F5000 ; lift nozzle
M109 S200 ; set temperature and wait for it to be reached
G21 ; set units to millimeters
G90 ; use absolute coordinates
M82 ; use absolute distances for extrusion
; Filament gcode
G1 Z0.240 F7800.000
G1 E-2.00000 F2400.00000
G1 X85.933 Y80.302 F7800.000
It looks like an error - I think the right speed should be 60x12 mm/s = 720 mm/min, not 7800 mm/min.
Can you try using the latest PrusaSlicer release 2.2.0 to see if the output is the same or the error has been corrected?
Maybe you could zip and upload the project 3mf file.
Yes, that seems to be the problem. If I read right, it is not fixed in 2.2.0.
Still, Marlin should limit the speed to 12 mm/s even if a move is set to 7800 mm/min:
M203 X500 Y500 Z12 E120 ; sets maximum feedrates, mm/sec
I see this as two problems, the first is that PrusaSlicer should not generate speeds exceeding max feed rate for a given axe and second Marlin should limit speeds to max given in M203.
I have just downloaded the latest release of Slic3r and the creates exactly the same code without the block of code for limits.
I have not tried the code yet but I will and see if without the limits block marlin speed limits are adhered to. Ie if it actually gets the nozzle at a correct distance from the bed to print.
there are more settings here are similar comparisons for an ender 3
have you set up the print speed settings. for your printer?
from the above images you can see that the Maximum feed rates for the Ender3 match those of your setup, and are higher than those of the Prusa Mk3,
but the speed settings for the Ender3 in the 0.2mm layer profile are way below the settings for the Prusa. and way below the maximum settings,
I believe the Ender Acceleration settings on the Ender3, being set to zero, passes responsibility for acceleration to the Printer firmware.
Thanks for the suggestions Joan,
I have been through all the settings i can and set them to 0 or to match the Marlin settings for speed / acceleration. I have just tried a XYZ test cube print and still have the problem with the initial z move after G29 bed leveling.
I have tried Slic3r 1.3.0 too and its the same code and problem.
Guess I stick with Cura for now.
Set your Gcode flavour to Reprap/Sprinter instead of Marlin. When in that flavour it doesnt put in anything automatically, it will only have your specified gcode from your start and the sliced stuff. Try it and do a compare.
I switched to Reprap/Sprinter and see no difference
G1 Z0.100 F7800.000
preset crap before printing is there again.
Many people want to do a drip clean up at this point (home position), and go up very slowly to Z15, or Z10.
This method is very effectiv. The filament is pulled up and does not smear around the nozzle and bed like with an "intro line".
With this preset, not removeable code, the nozzle runs into that dripped filament again... 😠
I did a bit of experimenting. That G1 Z0.100 F7800.000 is the extruder moving to the start of the print job after all the start up gcode. The Fxxxx.xxx seems to be directly set by the Travel speedx60 as configured under the Print settings>Speed>Speed for Non Print Moves>Travel.
If I set 100 in there the F value becomes 6000, if I set 120 it becomes 7200 etc. I think the x60 is fixed as I couldnt find anywhere where a value of 60 was used elsewhere in my configuration but it could be some other resultant of several values being plugged in.
It could still possibly be a bug but its also possible that 'some' firmware is expecting those in xx/per minute which would make sense as the setting is set in mm/s, then a multiply by 60 would give you a per minute value.
Anyway you now know what setting controls that value. As far as I can see the same value is used for ALL travel moves so that feedrate will be scattered throughout your gcode.
Is this bug going to be fixed?
As of v2.2.0 I'm still confirming this behavior.
Setting travel speed to 30 mm/s gives
G1 Z0.400 F1800.000
As a first move, which is too much for my printer.
Is it going to acknowledge machine limit settings?
I mentioned this on a different thread on github as someone was having a slightly related issue. The view is that machine firmware is supposed to limit anything from going beyond what it’s capable of. So the question is why is your machine firmware not obeying it set speed limits ? It shouldn’t go faster than the limits set in its eeprom.
So the question is why is your machine firmware not obeying it set speed limits ?
Actually, a good question)
Set me a
This fixed the problem
do you solve it, changing values in marlin or in the prusaslicer?