Ender3 v2 x-axis limit switch

[lmcjerl 0]

I just install an auto-bed levelling and I'm seeing a strange behaviour on my far left print:when the print he

Edited November 30, 2023 by lmcjerl

[lmcjerl 0]

My first post, hit ctrl-enter!
To continue:

 

When the print head goes left and hit the x-axis limit switch, near 3 mm for the suppose edge, the head print, but no x movement possible, so the first 3 mm is all screw up.
Since this seem to be an HW behaviour, I decided to change the creality_ender3.def.json to add a new disallowed area (added more space to also go farther to the initial print head startup procedure):

"machine_disallowed_areas":
        {
            "default_value": [
                [
                    [-117.5, 117.5],
                    [-117.5, 108],
                    [117.5, 108],
                    [117.5, 117.5]
                ],
                [
                    [-117.5, -108],
                    [-117.5, -117.5],
                    [117.5, -117.5],
                    [117.5, -108]
                ],
                [
         [-117.5, 117.5],
                    [-112.5, 117.5],
                    [-112.5, -117.5],
                    [-117.5, -117.5]
                ]
            ]
        },

 

I'm not sure if I'm the only one with the problem, if others do have this, than maybe you should tell me how I can request a configuration change request?

Thanks,
/Jerome

[Slashee_the_Cow 436]

If it's a problem caused by something you've added to the printer, then they won't change the default configuration file, and I'm 99.99% sure they wouldn't add one for people with your specific problem. The machine definitions that ship with Cura are based on a "fresh out of the box" printer. I guess technically I should provide a link to the feature request form on the Cura GitHub repo, but trust me, it'd be a waste of your time and whoever there deals with it's.

 

I never liked the disallowed areas (had an Ender-3 v2 Neo - made a custom profile based on the E3/E3V2 but updated to include things like ABL in the startup gcode - until it sustained a fatal injury due to crappy filament), mostly because they didn't work - I could place stuff in Cura that would go past the printer's maximum printable area. So I just removed the disallowed areas and changed the bed size down to 220 x 220.

 

I'm assuming triggering the endstop makes it think it's at 0 when it isn't. Try adding this to the end of your startup gcode:

G0 X3
G92 X0

Every time the printer auto homes, it'll trigger the endstops on each axis because it can't trust where the stepper motors are. When your sensor triggers the endstop, it will think that is 0mm, when actually it's about 3mm in. That code moves the head to 3mm in from the edge (also known as "where you can actually start printing") and then updates the printer's coordinates to say that that is now the 0 point on the X axis. Now you can position things at X 0mm in Cura and they'll start 3mm in from the edge. Just make sure you take into account that now you have 3mm less space on the right.

[lmcjerl 0]

Thanks for the quick response Slashee.

I did not do any modification, beside the new added 3D touch mount, which do not seem to be the problem: moving the print-head manually show the metal part of the print head touching the x limit switch at about 3 mm, and completely stop at about 1 mm to the bed edge.
That is why I'm asking if other Ender 3 v2 owner have similar issue (my unit might be an exception, and if it is the case, will not bother to ask Ultimaker to do the change).

I only have 1 mm on the right side (if I want to keep my bed width to default 235.0 mm), note that I could move the glass bed on the metal surface about 3 mm to the right. Your solution would then be perfect (I will think about it).

My solution to add an excluded position is currently preventing of printing over the initial purge, here is the original part of the G-Code for the purge:

G1 X0.1 Y20 Z0.3 F5000.0 ; Move to start position

G1 X0.1 Y200.0 Z0.3 F1500.0 E15 ; Draw the first line

G1 X0.4 Y200.0 Z0.3 F5000.0 ; Move to side a little

G1 X0.4 Y20 Z0.3 F1500.0 E30 ; Draw the second line

 

Should Cura prevent printing over this purge area (I know I can try to remove it every time before the print, but this is tedious)?
 

Thanks,

/Jerome

 

P.S. I found out there is a "Creality Ender-3 Pro" configuration that is identical to the "Creality Ender-3 / Ender-3 v2", but have no disallowed areas, I might use if/when I will need to print full width/height, but I will need to be careful about limit switch and bed surface holder.

[Slashee_the_Cow 436]

You can change the startup g-code (which includes that nose wipe) by going into Preferences > Configure Cura... > Printers > [your printer here] > Machine Settings but I wouldn't remove the purge, just add 3 to the X values to make the gcode sequence:

G1 X3.1 Y20 Z0.3 F5000.0 ; Move to start position

G1 X3.1 Y200.0 Z0.3 F1500.0 E15 ; Draw the first line

G1 X3.4 Y200.0 Z0.3 F5000.0 ; Move to side a little

G1 X3.4 Y20 Z0.3 F1500.0 E30 ; Draw the second line

 

I don't think start/end gcode has to obey disallowed areas (nor do post-processing scripts, but unless you're using a script that moves things on the X axis for whatever reason you don't have to worry about it).

 

Hmm.... a post processing script that moves everything on the X axis... probably wouldn't actually be that hard. Want me to have a crack at making a post-processing script that moves everything on the X axis so you can start at 0 and have the script add 3 to everything?

[lmcjerl 0]

Thanks Slashee, if nobody else report problem with the Ender 3 v2, I will manage this offset manually (I prefer my disallowed solution since it does not need any other tweaking, I just need to update the file every time I will upgrade Cura, I can use the "Creality Ender-3 Pro" if I need to remove disallowed area).

 

/Jerome