Help with Cura!?

[Whoahoo]

Hi all.
I’m another newbie to 3D printing so please bear with me and hoping someone can help?

I have an Creality Ender V3 KE that I have recently purchased. I have successfully printed a couple of things and I’m absolutely hooked. However, I downloaded Cura as it came highly recommended and I have been getting on very will with the program albeit a bit of a learning curve! Here’s my issue. When I save the sliced item and open it in Creality Print to check/print it tells me the path goes beyond plate bounds and I have to go back into Cura to reposition. Sometimes it works, sometimes not and gives the same out of bounds error. I can’t understand why as I have loaded the correct printer and checked the start/end G-Codes are the same as the one found on the Creality website.
I have checked the bed size in both programs and are the same. When it does print, it’s fine so the alignment is okay, I guess. Any ideas? I’m sure it’s a setting somewhere or maybe something else? I have also noticed that the purge line is off the bed to the left and found somewhere stating to remove the minus from the start g-code G1 which I did and moved the purge line over to the right but it still kicks out the same message unless I reposition the item.

Appreciate any help from peeps with a lot more knowledgeable than me! Thanks. Jon

[CrazyIvan]

Weird.

Have you ruled out this being a bug in the Creality software? Perhaps they already know and there is a software update available.

I have many, many prints under my belt with my Tina2 and Tina2S, all of them sliced on Cura, and never had a problem like this. If anything, I find Cura is too conservative on what it will slice – if a model encroaches on the plate boundary with even a line width to spare, it refuses to slice (when, in my opinion, it shouldn't). Therefore I doubt Cura is the problem, but you can check:

1. Load the Gcode file back into Cura and use the Preview mode to inspect the nozzle movements. The vertical slider on the right hand side of the screen previews layers, the slider along the bottom previews within the layer (or you can press the play button for an animation). By loading the Gcode, it will show you the start/end scripts as well (which it doesn't when you preview the sliced model rather than the Gcode).

2. If you inspect Cura output Gcode in a text editor you will see some comment lines near the beginning, including the min and max X and Y (these do not include the start/end scripts). If you want to check those are reporting accurately, it is possible to dissect the Gcode using a spreadsheet or word processor to extract all the X and Y prefixes, then sort them to find the min and max (but this will only work if using absolute coordinates not relative travel).

3. Feed the Gcode into a non-Creality and non-Ultimaker simulator (most of the slicers offer a simulator or a simulation mode).

If you confirm that Cura is not doing something stupid, the only conclusion left is that there is a bug in Creality. I suspect they are trying to be too clever – my Tinas do not check the Gcode before printing, they just follow it blindly. There is sense in that: 3D printers are just blind robots following instructions step by step, all the clever stuff is embodied in the slicer software. Why do it twice?

Your negative X purge line bothers me, but I have no specific knowledge of the Ender. The Tina would not go negative, the firmware won't do it (even if the mechanics can). I have moved my purge line from Y=6 to X=0 by editing the start script in my Cura printer settings, which is far less likely to conflict with an actual model (especially since Cura will not slice an actual model at X=0). Did you print anything successfully before you modified the purge line?

I assume you have manual controls: you could try manual movements of the nozzle to explore the actual range of travel – does it allow negative values? Is the print plate larger than the full range of movement available? It seems quite reasonable there is a reserved area of plate (eg negative coordinates) for purge lines and purge blocks.

However, in short, if you can't find anything wrong with the Cura output, you need to tackle Creality whether there's a bug.

[Whoahoo]

Hi

Thank you for replying so quickly. Really appreciate it.
I have always checked/simulated the g-code file in either Creality Print or in Orca (preview)and both came out the same with boundary issues. I did a search and google came up with a possible start G-Code problem...

Start G-Code
M220 S100 ;Reset Feedrate
M221 S100 ;Reset Flowrate

G28 ;Home

G92 E0 ;Reset Extruder
G1 Z2.0 F3000 ;Move Z Axis up
G1 X-2.0 Y20 Z0.28 F5000.0 ;Move to start position
M109 S{material_print_temperature_layer_0}
G1 X-2.0 Y145.0 Z0.28 F1500.0 E15 ;Draw the first line
G1 X-1.7 Y145.0 Z0.28 F5000.0 ;Move to side a little
G1 X-1.7 Y20 Z0.28 F1500.0 E30 ;Draw the second line
G92 E0 ;Reset Extruder
G1 E-1 F1800 ;Retract a bit
G1 Z2.0 F3000 ;Move Z Axis up
G1 E0 F1800

I changed:
G1 X2.0 Y20 Z0.28 F5000.0 ;Move to start position
G1 X2.0 Y145.0 Z0.28 F1500.0 E15 ;Draw the first line
G1 X1.7 Y145.0 Z0.28 F5000.0 ;Move to side a little
G1 X1.7 Y20 Z0.28 F1500.0 E30 ;Draw the second line

That seemed to move the purge line over to the right of the left hand side of the bed and its now previewed correctly on the bed in Crealtiy/Ocra. But on most objects it still gives me the out of bounds error.

Not sure about where to find the actual g-code itself to compare the Min/Max. I have not printed direct from Cura as yet due to what the simulation kicks out. Maybe I should just to see?

Just annoying as I really like Cura as compared to the other two.

[CrazyIvan]

Not sure about where to find the actual g-code itself to compare the Min/Max.

Having sliced, click "save to disk". That produces a .gcode file which you can then transport to the printer by any means suitable – or look at directly.

If you're saying Cura produces the problem but the Creality slicer doesn't, then slice the same model in both and look for the differences. Save to disk, don't send to the printer direct from the slicer.