Cura: Super slow travel speed

[mruiferreira]

I've updated from cura 4.2 to 4.4 and now when i start printing and the nozzle is travelling from the starting corner to the center of the build plate to start printing, the travel speed is extremely slow you can barely notice the hotend moving at all... downgrading to 4.2.

I am using the same settings i was using on 4.2, checked all speed settings and they are correct. travel speed at 100mm/s but on reality it's less than 1mm/s, i can't even see it moving.

[fieldOfView]

Please fill out the issue template. We are missing vital information to do anything about this, like what printer you use. Also what is your start gcode?

[mruiferreira]

Application version
4.4

Platform
Windows 10

Printer
Anycubic i3 Mega

Reproduction steps

1. Something you did.
   Installed cura 4.4 (was using 4.2)

1. Something you did next.
   Sliced a model without changing any settings

Actual results
The travel speed was extremely slow the print head wouldn't even visibly move.

Additional information
Downgraded back to 4.2 without changing any settings and the speed is correct in this version.

[smartavionics]

Please save the project file from 4.4 (File -> Save) and zip or rename the .3mf file and attach to this issue, thanks.

[fieldOfView]

Also what is your start gcode?

[Pugnator]

The same issue here, Anycubic i3Mega, the nozzle and the bed move very slow at the very beginning, when hotend and bed are calibrating.Below are the first 70 lines of Gcode I used

;FLAVOR:Marlin ;TIME:985 ;Filament used: 1.18923m ;Layer height: 0.3 ;MINX:65.758 ;MINY:20.871 ;MINZ:0.2 ;MAXX:144.241 ;MAXY:189.128 ;MAXZ:0.275 ;Generated with Cura_SteamEngine 4.4.0 M140 S60 M105 M190 S60 M104 S220 M105 M109 S220 M82 ;absolute extrusion mode G21 ;metric values G90 ;absolute positioning M82 ;set extruder to absolute mode M107 ;start with the fan off G28 X0 Y0 ;move X/Y to min endstops G28 Z0 ;move Z to min endstops G1 Z15.0 F100 ;move the platform down 15mm G92 E0 ;zero the extruded length G1 F200 E3 ;extrude 3mm of feed stock G92 E0 ;zero the extruded length again G1 F100 G0 Y20 F100 M117 Printing... G5 G92 E0 G92 E0 G1 F2400 E-6 ;LAYER_COUNT:1 ;LAYER:0 M107 M204 S3000 M205 X10 Y10 G1 F600 Z0.275 G0 F3000 X66.114 Y24.278 Z0.275 M204 S1800 M205 X8 Y8 ;TYPE:SKIRT G1 F600 Z0.2 G1 F2400 E0 G1 X66.385 Y23.685 E0.04554 G1 X66.727 Y23.13 E0.09107 G1 X67.134 Y22.62 E0.13665 G1 X67.601 Y22.165 E0.18219 G1 X68.119 Y21.77 E0.22769 G1 X68.683 Y21.441 E0.27329 G1 X69.282 Y21.183 E0.31885 G1 X69.908 Y21.001 E0.36438 G1 X70.552 Y20.897 E0.40994 G1 X71.078 Y20.871 E0.44673 G1 X138.921 Y20.871 E5.18531 G1 X139.572 Y20.911 E5.23087 G1 X140.213 Y21.03 E5.2764 G1 X140.835 Y21.227 E5.32197 G1 X141.427 Y21.498 E5.36745 G1 X141.983 Y21.84 E5.41304 G1 X142.492 Y22.248 E5.4586 G1 X142.948 Y22.714 E5.50414 G1 X143.343 Y23.233 E5.5497 G1 X143.671 Y23.796 E5.59521 G1 X143.929 Y24.395 E5.64076 G1 X144.111 Y25.021 E5.6863 G1 X144.215 Y25.665 E5.73186

[fieldOfView]

Also what is your start gcode?

In other words, what is the text entered in the Start GCode box in Preferences -> Printers -> Machine Settings? This contains some replacement patterns (text between {} curly brackets) which are not visible now. If you show us that Start GCode snippet, we can probably make suggestions how to improve your snippet.

Without having seen the actual Start GCode snippet, I can only guess it is using {speed_print} or {speed_travel} replacement patterns. In Cura, these settings are specified in mm/s, but Marlin needs mm/minute (for reasons, I am sure). So the value that gets put in the gcode may be 60 times lower than what you would expect. If this is the case, hardcoding a saner value may be your only option.

[Pugnator]

G21 ;metric values G90 ;absolute positioning M82 ;set extruder to absolute mode M107 ;start with the fan off G28 X0 Y0 ;move X/Y to min endstops G28 Z0 ;move Z to min endstops G1 Z15.0 F{speed_travel} ;move the platform down 15mm G92 E0 ;zero the extruded length G1 F200 E3 ;extrude 3mm of feed stock G92 E0 ;zero the extruded length again G1 F{speed_travel} G0 Y20 F{speed_travel} M117 Printing... G5

[fieldOfView]

Looks like this is indeed the mm/s vs mm/min thing. Change all 3 occurrences of F{speed_travel} with F6000.

[Pugnator]

Looks like this is indeed the mm/s vs mm/min thing. Change all 3 occurrences of F{speed_travel} with F6000.

that did the trick, thanks

[Ghostkeeper]

Not sure how we should deal with this bug. Cura is sort of doing what it's expected to do: fill in the value of the setting there. But the user is expecting it to be multiplied by 60 in order to get a correct result.

[Ghostkeeper]

We've decided to defer this. We could make an option to perform mathematics in those replacement keys, like dividing by 60, or we could automatically do the mathematics for the user if we detect it's in an F parameter. But none of it is too important. Hard-coding those speeds in the start g-code works fine enough for now.

[kevquinn]

Tripped over this, having just found that the default start/end g-code for an old printer I pulled out of retirement has "F{speed_travel}" coded into it, which (for Marlin firmware at least) doesn't achieve what the author of that start/end g-code wanted.

38 of the printer definitions have that specific case (as of 4.6.1). I guess it's up to whoever contributed those definitions to sort them out :)